Carrier 48-50PD05 User Manual

48/50PD05,06
Single Package Displacement Ventilation
or Single Zone Variable Airflow Rooftop Units
Electric Cooling/Gas Heating with PURONR (R--410A)
Refrigerant and COMFORTLinkt 1.x Controls

Controls, Start--Up, Operation, Service and

Troubleshooting Instructions

TABLE OF CONTENTS

Page

SAFETY CONSIDERATIONS 2.........................

GENERAL 3.........................................

BASIC CONTROL USAGE 3...........................

ComfortLinkt Control 3..............................

Scrolling Marquee 3..................................

Accessory Navigator Display 3..........................

Operation 3.........................................

System Pilott Device 4...............................

CCN Tables and Display 4.............................

Conventions Used in This Manual 5......................

START--UP 5.........................................

Unit Preparation 5....................................

Compressor Mounting 5...............................

Refrigerant Service Ports 5.............................

Crankcase Heater(s) 5.................................

Compressor Rotation 5................................

Power Supply 6.....................................

Internal Wiring 6.....................................

Evaporator Fan 6....................................

Condenser Fans and Motors 6...........................

Return--Air Filters 6..................................

Outdoor--Air Inlet Screens 6............................

Accessory Installation 7...............................

Orifice Change (48PD Only) 7..........................

Gas Heat (48PD Only) 7...............................

CONTROLS QUICK SET--UP 7.........................

Control Set Point and Configuration Log 7................

Standard Unit Control 7...............................

CCN Communication 8...............................

Accessories 8.......................................

Programming Operating Schedules 10....................

SERVICE TEST 10....................................

Independent Outputs 10...............................

Fan Test 10.........................................

Cooling Test 11.....................................

Heating Test 11......................................

THIRD PARTY CONTROL 11..........................

Remote Occupancy 11................................

Fire Shutdown 11....................................

Alarm Output 11.....................................

Economizer Monitoring 11.............................

Economizer Damper Control 11.........................

CONTROLS OPERATION 11...........................

Display Configuration 11..............................

Modes 12..........................................

Unit Configuration 12.................................

General Operating Sequence 13.........................

Occupancy Determination 13

Compressor Operation 14..............................

Indoor Fan Operation 14...............................

Outdoor Fan Operation 15.............................

Economizer Operation 15..............................

Indoor Air Quality (IAQ) 16............................

Cooling Modes 17...................................

Heating Modes 20....................................

Temperature Compensated Start 22.......................

Carrier Comfort Network (CCN)R Configuration 23.........

Demand Limit 23....................................

Alarm Handling 24...................................

TROUBLESHOOTING 2 4..............................

Complete Unit Stoppage 24............................

Restart Procedure 24..................................

Control Module Communication 24......................

Communication Failures 25............................

Alarms and Alerts 25.................................

Cooling Troubleshooting 30............................

Digital Scroll Controller (DSC) Troubleshooting 31..........

Economizer Troubleshooting 33.........................

Heating Troubleshooting 34............................

Variable Frequency Drive (VFD) Troubleshooting 34........

Phase Loss Protection 34..............................

Thermistor Troubleshooting 37.........................

Transducer Troubleshooting 38.........................

Forcing Inputs and Outputs 38..........................

MAJOR SYSTEM COMPONENTS 42....................

General 42.........................................

Main Base Board (MBB) 47............................

Economizer Control Board (ECB) 49.....................

Modulation Board (AUX1) 51..........................

Digital Scroll Control Board (DSC) 52....................

...........................

Variable Frequency Drive (VFD) 53......................

Integrated Gas Control (IGC) Board 54...................

Low Voltage Terminal Strip (TB1) 55.....................

Scrolling Marquee Display 56..........................

Accessory Navigatort Display 56.......................

Carrier Comfort Network (CCN)R Interface 56.............

Field--Installed Accessories 56..........................

SERVICE 59.........................................

Cleaning 60........................................

Lubrication 62......................................

Evaporator Fan Service and Replacement 62...............

Evaporator Fan Performance Adjustment 62...............

Evaporator Fan Belt Tension Adjustment 63...............

Variable Frequency Drive (VFD) Replacement 63...........

Condenser--Fan Adjustment 63..........................

Verify Sensor Performance 64..........................

48/50PD

Economizer Operation During Power Failure 64............

Evacuation 64.......................................

Refrigerant Charge 64.................................

Gas Valve Adjustment (48PD Units Only) 65...............

High Altitude (48PD Units Only) 66.....................

Main Burners (48PD Units Only) 66.....................

Filter Drier 66.......................................

Protective Devices 66.................................

Relief Devices 67....................................

Compressor Sound Shield 67...........................

Control Circuit, 24--V 67..............................

Replacement Parts 67.................................

Diagnostic LEDs 67..................................

APPENDIX A -- LOCAL DISPLAY AND

CCN TABLES 68.....................................

APPENDIX B -- STARTUP DATA 81.....................

APPENDIX C -- ADDITIONAL STARTUP DATA 91.........

APPENDIX D -- ADDITIONAL STARTUP DATA 100.......

UNIT START--UP CHECKLIST 105......................

SAFETY CONSIDERATIONS

Installation and servicing of air-conditioning equipment can be
hazardous due to system pressure and electrical components. Only
trained and qualified service personnel should install, repair, or
service air-conditioning equipment. Untrained personnel can
perform the basic maintenance functions of replacing filters.
Trained service personnel should perform all other operations.

When working on air-conditioning equipment, observe precautions
in the literature, tags and labels attached to the unit, and other
safety precautions that may apply. Follow all safety codes. Wear
safety glasses and work gloves. Use quenching cloth for unbrazing
operations. Have fire extinguishers available for all brazing
operations.

Follow all safety codes. Wear safety glasses and work gloves.
Have fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions attached to the unit.
Consult local building codes and National Electrical Code (NEC)
for special requirements.

Recognize safety information. This is the safety--alert symbol
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and
CAUTION. These words are used with the safety--alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies a hazard
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or
operation.

!

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause personal
injury or death.

Before performing service or maintenance operations
on unit, turn off main power switch to unit and install
lockout tag. Ensure electrical service to rooftop unit
agrees with voltage and amperage listed on the unit
rating plate.

!

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may cause equipment
damage.

This unit uses a microprocessor--based electronic control
system. Do not use jumpers or other tools to short out
components or to bypass or otherwise depart from
recommended procedures. Any short--to--ground of the
control board or accompanying wiring may destroy the
electronic modules or electrical components.

!

WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

Improper installation, adjustment, alteration, service, or
maintenance can cause property damage, personal
injury, or loss of life. Refer to the User’s Information
Manual provided with this unit for more details.
Do not store or use gasoline or other flammable vapors
and liquids in the vicinity of this or any other appliance.

What to do if you smell gas:

1. DO NOT try to light any appliance.

2. DO NOT touch any electrical switch, or use any
phone in your building.

3.IMMEDIATELY call your gas supplier from a

neighbor’s phone. Follow the gas supplier’s
instructions.

4. If you cannot reach your gas supplier, call the fire

department.

.

2

GENERAL

This publication contains Start--Up, Controls, Operation, Service,
and Troubleshooting information for the 48/50PD rooftop units.
(See Table 1.) These units are equipped with ComfortLinkt
controls version 1.X or higher and use Puronr refrigerant. The
specific base unit installation instructions and/or wiring label
diagram may also be required in conjunction with this book as a
guide to a specific unit on the roof. All the units in Table 1 are
Displacement Ventilation or Single Zone Variable Airflow units
that provide stand--alone or network operation.

Table 1 — Rooftop Units

MODEL SIZE NOMINAL TONS

48/50PD

05 4
06

5

BASIC CONTROL USAGE

ComfortLink Control

The ComfortLink control is a comprehensive unit-management
system. The control system is easy to access, configure, diagnose
and troubleshoot.

The ComfortLink control is fully communicating and cable-ready
for connection to the Carrier Comfort Network® (CCN) building
management system. The control provides high-speed
communications for remote monitoring via the Internet. Multiple
units can be linked together (and to other ComfortLink control
equipped units) using a 3-wire communication bus.

The ComfortLink control system is easy to access through the use
of a unit-mounted display module. There is no need to bring a
separate computer to this unit for start-up. Access to control menus
is simplified by the ability to quickly select from 11 menus. A
scrolling readout provides detailed explanations of control
information. Only four, large, easy-to-use buttons are required to
maneuver through the entire controls menu. The display readout is
designed to be visible even in bright sunlight.

For added service flexibility, an accessory hand-held
Navigator™ module is also available. This portable device has an
extended communication cable that can be plugged into the unit’s
communication network at the main control box. The Navigator
display provides the same menu structure, control access and
display data as is available at the unit-mounted Scrolling Marquee
display.

S Service Test
S Temperatures
S Pressures
S Set points
S Inputs
S Outputs
S Configuration
S Timeclock
S Operating Modes
S Alarms

Through the Scrolling Marquee, the user can access all of the
inputs and outputs to check on their values and status, configure
operating parameters plus evaluate the current decision status for
operating modes. The control also includes an alarm history which
can be accessed from the display. In addition, through the Scrolling
Marquee, the user can access a built-in test routine that can be used
at start-up commissioning and to diagnose operational problems
with the unit.

Accessory Navigator Display

The accessory hand-held Navigator display can be used with the
48/50PD units. (See Fig. 2.) The Navigator display operates the
same way as the Scrolling Marquee device. The Navigator display
is plugged into the LEN (local equipment network) port on either
TB1 or the J3 port on the ECB (economizer control board).

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48/50PD

MODE

Run Status

Service Test

Temperature

Pressures

Setpoints

Inputs

Outputs

Configuration

Time Clock

Operating Modes

Alarms

Alarm Status

ESCAPE

ENTER

C06320

Fig. 1 -- Scrolling Marquee

Scrolling Marquee

This device is the keypad interface used to access the control
information, read sensor values, and test the unit. The Scrolling
Marquee is located in the main control box and is standard on all
units. The Scrolling Marquee display is a 4-key, 4-character,
16-segment LED (light-emitting diode) display module. The
display also contains an Alarm Status LED. (See Fig. 1.)

The display is easy to operate using 4 buttons and a group of 11
LEDs that indicate the following menu structures:

S Run Status

C06321

Fig. 2 -- Accessory Navigator Display

Operation

All units are shipped from the factory with the Scrolling Marquee
display, which is located in the main control box. (See Fig. 1.) In
addition, the ComfortLink control also supports the use of the
handheld Navigator display.

Both displays provide the user with an interface to the
ComfortLink control system. The displays have up and down
arrow keys, an ESCAPE key and an ENTER key. These keys are
used to navigate through the different levels of the display
structure. The Navigator display and the Scrolling Marquee operate
in the same manner, except that the Navigator display has multiple
lines of display and the Scrolling Marquee has a single line. All
further discussions and examples in this document will be based on
the Scrolling Marquee display. See Table 2 for the menu structure.

The four keys are used to navigate through the display
structure, which is organized in a tiered mode structure. If the
buttons have not been used for a period, the display will default to
the AUTO VIEW display category as shown under the RUN
STATUS category. To show the top-level display, press the
ESCAPE key until a blank display is shown. Then use the up and

3

down arrow keys to scroll through the top-level categories. These
are listed in Appendix A and will be indicated on the Scrolling
Marquee by the LED next to each mode listed on the face of the
display.

When a specific mode or sub-mode is located, push the ENTER
key to enter the mode. Depending on the mode, there may be
additional tiers. Continue to use the up and down keys and the
ENTER keys until the desired display item is found. At any time,
the user can move back a mode level by pressing the ESCAPE key.
Once an item has been selected the display will flash showing the
item, followed by the item value and then followed by the item
units (if any).

Items in the Configuration and Service Test modes are password
protected. The display will flash PASS and WORD when required.
Use the ENTER and arrow keys to enter the four digits of the
password. The default password is 1111.

Pressing the ESCAPE and ENTER keys simultaneously will scroll
an expanded text description across the display indicating the full
meaning of each display point. Pressing the ESCAPE and ENTER
keys when the display is blank (MODE LED level) will return the
display to its default menu of rotating AUTO VIEW display items.

48/50PD

In addition, the password will need to be entered again before
changes can be made.

Changing item values or testing outputs is accomplished in the
same manner. Locate and display the desired item. If the display is
in rotating auto-view, press the ENTER key to stop the display at
the desired item. Press the ENTER key again so that the item value
flashes. Use the arrow keys to change the value of state of an item
and press the ENTER key to accept it. Press the ESCAPE key and
the item, value or units display will resume. Repeat the process as
required for other items.

There are some points that can be forced from the Scrolling
Marquee or the Navigator. If the user needs to force a variable,
follow the same process as when editing a configuration parameter.
A forced variable, regardless where the force has come from will
be displayed with a blinking “.” on a Scrolling Marquee and a
blinking “f” on a Navigator following its value. For example, if

economizer commanded position (EC.CP) is forced, the Navigator
display shows “80f”, where the “f” is blinking to signify a force on
the point. The Scrolling Marquee display shows “80.” Where the
“.” is blinking to signify a force on the point. Remove the force by
selecting the point that is forced with the key ENTER and then
pressing the up and down arrow keys simultaneously.

Depending on the unit model, factory-installed options and
field-installed accessories, some of the items in the various Mode
categories may not apply.

System Pilott and Touch Pilot Devices

The System Pilot device (33PILOT--01) and Touch Pilot device
(33CNTPILOT) can be used as CCN communication
user--interfaces. These devices can be put on the CCN bus and
addressed to communicate with any other device on the network.
Unlike the Scrolling Marquee and Navigator, these pilots read the
48/50PD’s CCN tables and the units CCN points can be monitored,
forced, or configured.

IMPORTANT: Multiple zoning application is NOT
recommended at this time with the PD products.

Additionally, the System Pilot device can serve as a wall--mounted
temperature sensor for space temperature measurement. The
occupant can use the System Pilot device to change set points. A
security feature is provided to limit access of features for
unauthorized users. See Fig. 3 for System Pilot device details.

CCN Tables and Display

In addition to the unit--mounted Scrolling Marquee display, the
user can also access the same information through the CCN tables
by using the Service tool or other CCN programs/devices. The
variable names used for the CCN tables and the Scrolling Marquee
menus may be different and more items may be displayed in the
CCN tables. Details on the CCN tables are included with the local
display menus in Appendix A. Appendix A is structured towards
the organization of the local display (Scrolling Marquee) menus.
Because of the variety of CCN programs and devices, the CCN
tables, sub-- tables, and points are referenced within that
organization.

RUN

STATUS

Auto View

of

Run Status

(VIEW)

↓

Software

Version

Numbers

(VERS)

↓

Control

Modes

(MODE)

↓

Cooling

Status

(COOL)

↓

Heating

Status

(HEAT)

↓

Economizer

Status

(ECON)

↓

Component

Run Hours

(HRS)

↓

Component

Starts

(STRT)

SERVICE

TEST

Service Test

Mode

(TEST)

↓

Test Independent

Outputs

(INDP)

↓

Tes t Fa n s

(FANS)

↓

Test Cooling

(COOL)

↓

Test Heating

(HEAT)

Table 2 — Scrolling Marquee Mode and Menu Display Structure

TEMPERATURES PRESSURES SETPOINTS INPUTS OUTPUTS CONFIGURATION

Air

Temperatures

(AIR.T)

↓

Refrigerant

Temperatures

(REF.T)

General

Inputs

(GEN.I)

↓

Current

Sensor Inputs

(CS.IN)

↓

Air Quality

Inputs

(AIR.Q)

Fan
Outputs
(FANS)

↓

Cool
Outputs
(COOL)

↓

Heat
Outputs
(HEAT)

↓

Economize

r
Outputs
(ECON)

↓

Alarm

Relay

(ALRM)

Display

Configuration

(DISP)

↓

Unit

Configuration

(UNIT)

↓

Cooling

Configuration

(COOL)

↓

Heating

Configuration

(HEAT)

↓

Economizer

Configuration

(ECON)

↓

Air Quality

Cfg.

(AIR.Q)

↓

Alarm Relay

Config.

(ALM.O)

↓

PID

Configuration

(PID)

↓

Sensor

Calibration

(TRIM)

↓

CCN

Configuration

(CCN)

TIME

CLOCK

Tim e o f Da y

(TIME)

↓

Month, Date

Day an d

Year

(DATE)

↓

Daylight

Savings

Tim e

(DST)

↓

Local Time

Schedule
(SCH.L)

↓

Local

Holiday

Schedules

(HOL.L)

OPERATIN

G

MODES

Control

Modes

(MODE)

↓

Cool Mode

Diagnostic

(COOL)

↓

Heat Mode

Diagnostic

(HEAT)

↓

Economizer

Diagnostic

(ECON)

↓

Demand

Listing

(DMD.L)

ALARMS

Reset All

Current
Alarms

(R.CURR)

↓

Reset

Alarm

History

(R.HIST)

↓

Currently

Active

Alarms

(CURR)

↓

Alarm

HIstory

(HIST)

4

NAVIGATE/

/

EXIT

SCROLL

Fig. 3 -- System Pilott User Interface

+

-

PAGE

MODIFY
SELECT

C06322

Force Hierarchy

There is a hierarchy in CCN with regards to forcing a point.
Programs and devices write a force at different priority levels. A
higher level (smaller number, 1 being the highest) will override a
lower level force. The Scrolling Marquee uses a Control Force at
level 7. The Navigator writes a Service Force which is level 3.
System Pilots and Touch Pilots write Supervisor Forces at level 4.
Network programs can be set to write different level priority forces.

Generic Status Display Table

The GENERIC points table allows the service/installer the ability
to create a custom table in which up to 20 points from the 5 CCN
categories (Points, Config, Service--Config, Set Point, and
Maintenance) may be collected and displayed.

In the Service-- Config table section, there is a table named
“GENERICS.” This table contains placeholders for up to 20 CCN
point names and allows the user to decide which points are
displayed in the GENERIC points sub--table under the status
display table. Each one of these placeholders allows the input of an
8--character ASCII string. Using a CCN interface, enter the Edit
mode for the Service--Config table “GENERICS” and enter the
CCN name for each point to be displayed in the custom points
table in the order they will be displayed. When done entering point
names, download the table to the rooftop unit control.

IMPORTANT: The computer system software (ComfortVIEWt,
Service Tool, etc.) that is used to interact with CCN controls,
always saves a template of items it considers as static (e.g., limits,
units, forcibility, 24--character text strings, and point names) after
the software uploads the tables from a control. Thereafter, the
software is only concerned with run time data like value and
hardware/force status. With this in mind, it is important that any
time a change is made to the Service--Config table “GENERICS”
(which in turn changes the points contained in the GENERIC point
table), that a complete new upload be performed. This requires that
any previous table database be completely removed first. Failure to
do this will not allow the user to display the new points that have
been created and the CCN interface will have a different table
database than the unit control.

Conventions Used in This Manual

The following conventions for discussing configuration points for
the local display (Scrolling Marquee or Navigator™ accessory) will
be used in this manual.

Point names will be written with the Mode name first, then any
submodes, then the point name, each separated by an arrow symbol
(→). Names will also be shown in bold and italics. As an example,
the Fan Status Switch which is located in the Configuration mode,
and Unit sub-mode would be written as Configuration→

UNIT→FN.SW.

This path name will show the user how to navigate through the
local display to reach the desired configuration. The user would
scroll through the modes and sub-modes using the up and down
keys. The arrow symbol in the path name represents pressing
ENTER to move into the next level of the menu structure.

When a value is included as part of the path name, it will be shown
at the end of the path name after an equals sign. If the value
represents a configuration setting, an explanation will be shown in
parenthesis after the value. As an example,
Configuration→UNIT→FN.SW = 1 (Normal Open).

Pressing the ESCAPE and ENTER keys simultaneously will scroll
an expanded text description of the point name across the display.
The expanded description is shown in the local display tables but
will not be shown with the path names in text.

The CCN point names are also referenced in the local display
tables for users configuring the unit with CCN software instead of
the local display. See Appendix A of this manual.

START-UP

IMPORTANT: Do not attempt to start unit, even momentarily,

until all items on the Start--Up Checklist (last page) and the
following steps have been completed.

Unit Preparation

Check that unit has been installed in accordance with these
installation instructions and all applicable codes.

Compressor Mounting

Compressors are internally spring mounted. Do not loosen or
remove compressor holddown bolts.

Refrigerant Service Ports

Each independent refrigerant system has a total of 3 Schrader-type
service gauge ports per circuit. One port is located on the suction
line, one on the compressor discharge line, and one on the liquid
line. Be sure that caps on the ports are tight.

Crankcase Heater(s)

Compressor crankcase heater operation varies depending on the
unit size and type. In general for all units, the crankcase heaters are
energized if there is power to the unit, the compressor is not
operating, and the ambient temperature is below 75_F.

IMPORTANT: Unit power must be on for 24 hours prior to
start--up. Otherwise, damage to compressor may result.

Compressor Rotation

!

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in unit damage.

Improper wiring will cause compressor stoppage and alarm.
Correct wiring by switching leads as indicated below.

48/50PD

5

CONTROL BOX

AND

COMPRESSOR

ELECTRICAL

OPTIONS PANEL

OUTDOOR AIR

SCREEN

(HIDDEN)

48/50PD

INDOOR MOTOR

ACCESS DOOR

GAS SECTION
ACCESS

CONDENSER COIL
ACCESS PANEL

BASEPAN CONNECTIONS

ACCESS PANEL

Fig. 4 -- Panel and Filter Locations

On 3-phase units, it is important to be certain the compressors are
rotating in the proper direction. To determine whether or not
compressors are rotating in the proper direction, use a
phase-rotation meter on the unit input power to check for
L1-L2-L3 or clockwise rotation or use the Service Test mode to
energize a compressor. If the compressor is rotating in the wrong
direction, the controls will stop the compressor and display alarm
for “Circuit A Failure to Pressurize.”

IMPORTANT: Indoor or outdoor fan rotation direction may not
indicate proper input power phase sequence, as some 3-phase units
use single-phase fan motors.

To correct the wrong compressor rotation direction, perform the
following procedure:

1. Turn off power to the unit and lock out the power.

2. Switch any two of the incoming unit power leads.

3. Turn on power to the unit.

4. Verify corrected compressor rotation.

Power Supply

All 208/230-v units are factory wired for 230-v power supply. If
the 208/230-v unit is to be connected to a 208-v power supply, the
transformers (TRAN1 and TRAN2) must be rewired by moving
the wire from the 230-volt connection and moving to the 200-volt
terminal on the primary side of the transformer. Refer to unit label
diagram for additional information.

Internal Wiring

Check all electrical connections in unit control boxes; tighten as
required.

Evaporator Fan

Fan belt and variable pulleys are factory-- installed, but may need to
be adjusted for specific applications. Be sure that the fans rotate in
the proper direction. See Appendix C for unit specific fan
performance data. See Appendix D for unit specific air quality

FILTER ACCESS DOOR

C07002

limits, evaporator fan motor specifications, FIOP static pressures,
and fan RPM for various motor pulley settings. Appendix C and D
are based on 100% fan speed (VFD at 60Hz). To alter fan
performance, see Evaporator Fan Performance Adjustment in the
Service section.

The Supply Fan Minimum Speed
(Configuration→UNIT→FS.MN) and the Supply Fan Maximum
Speed (Configuration→UNIT→FS.MX) can also be used to alter
fan performance. The fan should run at the maximum fan speed
when setting up the application design point. The unit is equipped
with a Variable Frequency Drive (VFD). The VFD’s settings
should not be used for adjusting fan performance. Specific VFD
information can be found in Appendix B.

IMPORTANT: When setting up and starting the unit, the heating
minimum CFM requirements must be upheld when changing belts,
pulleys, and configurations. During heating mode, the fan speed is
always set to Supply Fan Maximum Speed (FS.MX).

Condenser Fans and Motors

Condenser fans and motors are factory set. Refer to Condenser-Fan
Adjustment section as required.

Return--Air Filters

Check that correct filters are installed in filter tracks (see Physical
Data table in Installation Instructions). Do not operate unit without
return-air filters.

IMPORTANT: For units with 4-in. filter option, units are shipped
with standard 2-in. filters. To install 4-in. filters, the filter spacers
must be removed.

Outdoor--Air Inlet Screens

Outdoor-air inlet screens must be in place before operating unit.

6

Accessory Installation

Check to make sure that all accessories including sensors have
been installed and wired as required by the instructions and unit
wiring diagrams.

Orifice Change (48PD Only)

This unit is factory assembled for heating operation using natural
gas at an elevation from sea level to 2000 ft.

Use accessory high altitude kit when installing this unit at an
elevation of 2000 to 7000 ft. For elevations above 7000 ft, refer to
High Altitude section to identify the correct orifice size for the
elevation. Purchase these orifices from your local Carrier dealer.
Follow instructions in accessory Installation Instructions to install
the correct orifices.

Use accessory LP (liquid propane) gas conversion kit when
converting this unit for use with LP fuel usage for elevations up
to 7000 ft. For elevations above 7000 ft, refer to High Altitude
section to identify the correct orifice size for the elevation.
Purchase these orifices from your local Carrier dealer. Follow
instructions in accessory Installation Instructions to install the
correct orifices.

Gas Heat (48PD Only)

Verify gas pressures before turning on heat as follows:

1. Turn off field-supplied manual gas stop, located external to
unit.

2. Connect pressure gauge to supply gas tap, located on
field-supplied manual shutoff valve. (See F ig. 5.)

3. Connect pressure gauge to manifold pressure tap.

4. Turn on field-supplied manual gas stop. Enter Service Test
mode by setting Service Test→TEST to “ON” using the
Scrolling Marquee display. Use the Service Test feature to
set Service Test→HEAT→HT.1 to ON (first stage of heat)
using the Scrolling Marquee.

C06323

Fig. 5 -- Field Gas Piping

5. After the unit has run for several minutes, verify the supply
gas pressure is between 5.5--in. wg to 13.0-- in. wg, and the
manifold pressure is 3.50--in. wg on sizes 03-- 14 and 3.00
on size 16. If manifold pressure must be adjusted, refer to
Gas Valve Adjustment section.

IMPORTANT: Supply gas pressure must not exceed 13.0--in. wg.

6. Set Service Test→HEAT→HT.1 to OFF using Scrolling
Marquee.

7. Exit Service Test mode by setting Service Test→TEST to
“OFF” using the Scrolling Marquee.

CONTROLS QUICK SET--UP

The following information will provide a quick guide to setting up
and configuring the 48/50PD series units with ComfortLink™
controls. Unit controls are pre-configured at the factory for
factory-installed options. Field-installed accessories will require
configuration at start-up. Service Test is recommended for initial
start--up. Additionally, specific job requirements may require
changes to default configuration values. See the CCN and Display
parameter tables and other sections of these instructions for more
details.

Control Set Point and Configuration Log

During start up, accessory installation, and equipment service set
points and/or configuration changes might have to be made. When
setting set points or changing configuration settings,
documentation is recommended. The Control Log starting on page
106 should be filled out and left with the unit at all times. A copy
should also be provided to the equipment owner.

Standard Unit Control

There are two different applications these units can be applied to,
Displacement Ventilation and Single Zone VAV. F o r ei th er
application a direct wired space sensor can be used or a
communicating sensor/thermostat can be used. Installation of an
accessory supply air temperature (SAT) sensor in the supply duct is
recommended when using a communication type control. A supply
duct SAT measurement is valid for heating mode display, while the
factory--standard internal SAT is not valid for heating due to its
location upstream of the heating section. When installing the
supply duct SAT, the heating mode display is enabled by setting
Configuration→HEAT→SAT→SAT.H to ENBL.

There are several configurations that should be considered for
Displacement Ventilation or Single Zone VAV applications. Table
3 shows these configuration defaults and specific application
settings. These settings typical values and should be adjusted for
each actual specific unit application. Refer to the Operation section
for more detail on these configurations and how they effect the
units operation.

IMPORTANT: Multiple zoning application is not recommended
at this time with the PD product.

Space Temperature Sensor Control—Direct Wired
(T--55, T--56, or

Wire accessory space temperature sensor(s) to the T--55 terminals
on the field connection terminal board located at the unit control
box. No configuration is required when installing a T--55, T--56, or
T--59. Refer to Field-Installed Accessories section for additional
information.

T--58 Communicating Thermostat

Install the T -- 58 communicating thermostat. Connect the CCN
communication bus from the T--58 to the CCN terminals on the
field connection terminal board located at the unit control box.
Configure the unit’s CCN communication element number, bus
number, and baud rate. Configure the T --58’s CCN communication
bus number and baud rate the same as the unit, while the element
number has to be different. Configure the T--58 to send SPT to the
unit’s element number. Refer to the Field--Installed Accessories
section for additional information.

T--59)

48/50PD

7

Table 3 — Application Specific Configurations

ITEM EXPANSION DEFAULT UNITS

SASP Cool Supply Air Setpoint 65 dF 65 55

FS.MX Supply Fan Maximum Speed 100 % 100 100

FS.MN Supply Fan Maximum Speed 20 % 20 70

FS.VM Vent Mode Fan Speed 50 ∧F 50 50

MIN.C Min Compressor Capacity 70 % 15 70

FS.CD Fan Speed Control Demand 3 ∧F 3 3

SA.MU SASP Maximum Reset Up 10 ∧F 3 5

SA.MD SASP Maximum Reset Down --- 1 0 ∧F --- 3 --- 5

MP.MX Econ Min at Max Fanspeed 30 % 30 30

PE1.C Power Exhaust Stage 1 CFM 600 cfm 600 600

IDF.C Indoor Fan Max Speed CFM

System Pilot -- Communication Space Sensor

Install the System Pilot and connect the CCN communication bus
from it to the units CCN connection on the low voltage terminal

48/50PD

board. Configure the unit’s CCN communication element number,
bus number, and baud rate. Refer to the System Pilot’s installation
instructions for configuring it to be used as a space temperature and
attaching it to a unit.

Gen III TEMP Monitor -- Linkage Communication
Thermostat

Install the linkage thermostat. Connect the CCN communication
bus from the Stat to the CCN terminals on the field connection
terminal board located at the unit control box. Configure the unit’s
CCN communication element number, bus number, and baud rate.
Refer to the Linkage Thermostat’s installation instructions for
configuring the Stat and additional information about it.

(33CSTMT--01)

Space Humidistat Control

The humidistat input is provided on the field connection terminal
board. The Space Humidity Switch configuration,
Configuration→UNIT→RH.SW, identifies the normally open or
normally closed status of this input at LOW humidity. Humidistat
1 terminal is the 24 VAC source for dry contact and the Humidistat
2 terminal is the signal input.

Relative Humidity Sensor Control

For units with the economizer option (with the ECB--economizer
control board), the humidity sensor input is provided on the field
connection terminal board. The sensor can be used in addition to
or instead of a humidistat. The RH Sensor on OAQ Input
configuration, Configuration→UNIT→RH.S=YES, identifies that
the sensor is being used instead of an OAQ sensor. Terminal 1 is
the 24vdc loop power and Terminal 4 is the 4 --20 mA signal input.
Refer to the Field Installed Accessories for more information.

CCN Communication

Configure Configuration→CCN→CCN.A to desired element
number (Default is 1). Configure Configuration→CCN→ CCN.B
to desired bus number (Default is 0). Configure
Configuration→CCN→BAUD to desired code number for baud
rate (Default is 3 = 9600 baud).

Accessories

Below are quick configuration settings for field installed
accessories. If these accessories were installed by the factory, they
will already be configured. See the Field-- Installed Accessories
section, third party control, control connection tables, and CCN or
Display parameter tables for any accessories not mentioned below
and any additional information on accessories.

Economizer

If an Economizer accessory was field installed, the unit must be
configured for it by setting Configuration→ECON→EC.EN to
YES. The default settings for the other economizer configurations

1600 (05)
2000 (06)

cfm

should be satisfactory. If they need to be changed, additional
information about these configuration settings can be found in the
Economizer section.

Power Exhaust

If a Power Exhaust accessory was field installed, the unit must be
configured for it by setting Configuration→ECON→PE.EN to
ENBL. The default settings for the other power exhaust
configurations should be satisfactory. If they need to be changed,
additional information about these configurations can be found in
the Power Exhaust section.

Electric Heat

If an Electric Heat accessory was field installed, the unit must be
configured for it by setting Configuration→HEAT→HT.TY to a
value of 2. The number of electric heat stages must be configured
by setting Configuration→HEAT→N.HTR per the installed
heater.

Fire Shutdown

If a Fire Shutdown or Smoke Detector accessory was field
installed, the unit must be configured for it by setting
Configuration→UNIT→FS.SW to normally open (1) or normally
closed (2) when there is not a fire alarm. Normally open (1) is the
preferred configuration.

IMPORTANT: On standard units, the fire shutdown input is the
terminals Fire Shutdown 1 and 2.

Outdoor Enthalpy

If an Outdoor Enthalpy accessory was field installed, the unit must
be configured for it by setting Configuration→ECON→EN.SW,
identifies the normally open or normally closed status of this input
when the outdoor enthalpy is low.

IAQ Switch

If an IAQ Switch accessory was field installed, the unit must be
configured for it by setting Configuration→AIR.Q→II.CF,
identifies the normally open or normally closed status of this input
when the indoor air quality value is low (good) and also selects the
unit response to this input.

IMPORTANT: An IAQ switch cannot be used if an enthalpy
switch is already on this input.

IAQ Sensor

If an CO2Sensor accessory was field installed, the unit must be
configured for it by setting Configuration→AIR.Q→IA.CF
selects the unit response to this input. Default conversion to 0 to
2000 ppm.

OAQ Sensor

If an Outdoor Air Quality Sensor accessory was field installed, the
unit must be configured for it by setting Configuration→AIR.Q
→OA.CF selects the unit response to this input. Default
conversion to 0 to 2000 ppm.

DISPLACEMENT

VENTILATION

1600 (05)
2000 (06)

SINGLE ZONE

VAV

1600 (05)
2000 (06)

8

Fan Status

If a Fan Status accessory was field installed, the unit must be
configured for it by setting Configuration→UNIT→FN.SW to
normally open (1) or normally closed (2). Normally open (1) is the
preferred configuration.

IMPORTANT: Fan Status input is not on the terminals marked
Fan Status.

Table 4 — Setting an Occupied Time Schedule - Weekdays Only for 7:30 to 22:30

Filter Status

If a Filter Status accessory was field installed, the unit must be
configured for it by setting Configuration→UNIT→FL.SW to
normally open (1) or normally closed (2). Normally open (1) is the
preferred configuration.

DISPLAY

MENU

TIMECLOCK

SCH.L

SUB SUB

MODE

PER.1

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ENTER

Y

ENTER

Y

ENTER

ESCAPE

B

ENTER

ENTER

Y

ENTER

Y

ENTER

ESCAPE

B

ENTER

Y

ENTER

ESCAPE

B

ENTER

Y

ENTER

ESCAPE

B

ENTER

Y

ENTER

ESCAPE

B

ENTER

Y

ENTER

ESCAPE

B

ENTER

Y

ENTER

ESCAPE

ESCAPE

ESCAPE

ITEM DISPLAY ITEM EXPANSION COMMENT

Local Occupancy Schedule

OCC.1 Period Occupied Time

00.00

00.00

07.00

07.00

07.30

07.30

OCC.1 07.30 Period Occupied Time

UNC.1 00.00 Period Unoccupied Time

00.00

00.00

22.00

22.00

22.30

22.30

UNC.1 22.30 Period Unoccupied Time

MON.1 NO Monday In Period

NO

YES

YES

MON.1 YES Monday In Period

TUE.1 NO Tuesday In Period

NO

YES

YES

TUE.1 YES Tuesday In Period

WED.1 NO Wednesday In Period

NO

YES

YES

WED.1 YES Wednesday In Period

THU.1 NO Thursday In Period

NO

YES

YES

THU.1 YES Thursday In Period

FRI.1 NO Frida y In Perio d

NO

YES

YES

FRI.1 YES Friday In Period

Scrolling stops

Hours Flash

Select 7

Change accepted, minutes flash

Select 30

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Hours Flash

Select 22

Change accepted, minutes flash

Select 30

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Select YES

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Select YES

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Select YES

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Select YES

Change accepted

Item/Value/Units scrolls again

Scrolling stops

Select YES

Change accepted

Item/Value/Units scrolls again

48/50PD

9

Programming Operating Schedules

The ComfortLinkt controls will accommodate up to eight
different schedules (Periods 1 through 8), and each schedule is
assigned to the desired days of the week. Each schedule includes
an occupied on and off time. As an example, to set an occupied
schedule for 8 AM to 5 PM for Monday through Friday, the user
would set days Monday through Friday to ON for Period 1. Then
the user would configure the Period 1 Occupied From point to
08:00 and the Period 1 Occupied To point to 17:00. To create a
different weekend schedule, the user would use Period 2 and set
days Saturday and Sunday to ON with the desired Occupied On
and Off times.

IMPORTANT: By default, the time schedule periods are
programmed for 24 hours of occupied operation.

To create a schedule, perform the following procedure:

1. Scroll to the Configuration mode, and select CCN
CONFIGURATION (CCN). Scroll down to the Schedule
Number (Configuration→CCN→SCH.O=SCH.N). If
password protection has been enabled, the user will be
prompted to enter the password before any new data is

48/50PD

accepted. SCH.N has a range of 0 to 99. The default value
is 1. A value of 0 is always occupied, and the unit will
control to its occupied set points. A value of 1 means the
unit will follow a local schedule, and a value of 65 to 99
means it will follow a CCN schedule. Schedules 2-- 64 are
not used as the control only supports one internal/local
schedule. If one of the 2--64 schedules is configured, then
the control will force the number back to 1. Make sure the
value is set to 1 to use a local schedule.

2. Enter the Time Clock mode. Scroll down to the LOCAL
TIME SCHEDULE (SCH.L) sub--mode, and press
ENTER. Period 1 (PER.1) will be displayed.

3. Scroll down to the MON.1 point. This point indicates if
schedule 1 applies to Monday. Use the ENTER command
to go into Edit mode, and use the Up or Down key to
change the display to YES or NO. Scroll down through the
rest of the days and apply schedule 1 where desired. The
schedule can also be applied to a holiday.

4. Configure the beginning of the occupied time period for
Period 1 (OCC). Press ENTER to go into Edit mode, and
the first two digits of the 00.00 will start flashing. Use the
Up or Down key to display the correct value for hours, in
24--hour (military) time. Press ENTER and hour value is
saved and the minutes digits will start flashing. Use the
same procedure to display and save the desired minutes
value.

5. Configure the unoccupied time for period 1 (UNC). Press
ENTER to go into Edit mode, and the first two digits of the

00.00 will start flashing. Use the Up or Down key to display
the correct value for hours, in 24--hour (military) time. Press
ENTER and hour value is saved and the minutes digits will
start flashing. Use the same procedure to display and save
the desired minutes value.

6. The first schedule is now complete. If a second schedule is
needed, such as for weekends or holidays, scroll down and
repeat the entire procedure for period 2 (PER.2). If
additional schedules are needed, repeat the process for as
many as are needed. Eight schedules are provided. See
Table 4 for an example of setting the schedule.

The Service Test function can be used to verify proper operation of
compressors, heating stages, indoor fan, outdoor fans, power
exhaust fans, economizer, crankcase heaters, and the alarm relay.
Use of Service Test is recommended at initial system start up and
during troubleshooting (See Table 5 for point details).

Service Test mode has the following changes from normal
operation:

S Outdoor air temperature limits for cooling circuits, economizer,

and heating are ignored. Normal compressor time guards and

other staging delays are reduced to 30 seconds or less.

S Circuit alerts are limited to 1 strike (versus 3) before changing to

alarm shut down state.

S The status of ALM.N is ignored so all alerts and alarms are

broadcast on CCN.

S The words “SERVICE TEST” are inserted into every alarm

message.

Service test can only be turned ON/OFF at the unit display. Once
turned ON, other entries may be made with the display or through
CCN. To turn Service Test on, change the value of TEST to ON.
To turn service test off, change the value of TEST to OFF.

IMPORTANT: Service Test mode may be password protected.
Refer to Basic Control Usage section for more information.
Depending on the unit model, factory--installed options, and
field--installed accessories, some of the Service Test functions may
not apply.

Independent Outputs

The independent (INDP) submenu is used to change output status
for the economizer, power exhaust stages, crankcase heaters, and
the alarm relay. These independent outputs can operate
simultaneously with other Service Test modes. All outputs return to
normal operation when Service Test is turned off. When the
economizer is using the factory default Digital Control Type
(Configuration→ECON→E.CTL is 1 or 2) then the Economizer
Calibration feature may be used to automatically check and reset
the economizer actuator range of motion. Refer to the economizer
operation section of more details.

IMPORTANT: If a network force is applied to CCN points:
ECONOCMD, PE_1, PE_2, or ALMOUT, their respective test
mode functions will not be usable. Those forces are at a higher
level than test mode; therefore they will still be honored when in
test mode.

Fan Test

The fans (FANS) submenu is used to change output status for the
indoor fan and outdoor fan stages. The VFD power can be turned
on and off via IDF (Supply VFD Power Test). The indoor fan
speed test (F.SPD) runs the fan at the desired speed entered. The
outdoor fan relay test (OFC.1) only tests the relay for switching
between high and low speeds. The actual outdoor fan will not run
unless cool test is on. The cooling (COOL) and heating (HEAT)
service test outputs are reset to OFF for the fans service test.

SERVICE TEST

10

Cooling Test

The cooling (COOL) submenu is used to change output status for
testing the cooling function. The fans (FANS) and heating (HEAT)
service test outputs are reset to OFF for the cooling service test.
The digital scroll controller power test (CTLR) turns on and off the
compressor controller. The compressor capacity test (CPAC) is
used to run the compressor at a desired capacity of 15% to 100%.
If a capacity is chosen between 1 and 14, the capacity will be set to
15%. The outdoor fan will turn on to high speed when the
compressor capacity is 15% or greater. The indoor fan speed will
default to supply fan maximum speed (FS.MX) when the
compressor capacity test is first activated. The cool test fan speed
(F.SPD) is used to change the fan speed while the compressor is
running. All normal cooling alarms and alerts are functional.

IMPORTANT: When charging the unit, both the compressor
capacity test and the cool test fan speed should be set to 100%.

Heating Test

The heating (HEAT) submenu is used to change output status for
the individual heat stages, gas or electric. The fans (FANS) and
cooling (COOL) service test outputs are reset to OFF for the
heating service test. Indoor and outdoor fans are controlled
normally to maintain proper unit operation. The indoor fan speed
will run at the configured max speed FS.MX. All normal heating
alarms and alerts are functional.

Table 5 — Service Test Modes and Submodes Directory

DISPLAY MENU/
SUB--MENU/
NAME
SERVICE TEST

TEST

INDP Test Independent Outputs

ECON Economizer Position Test 0 to 100%
E.CAL Calibrate Economizer On/Off
PE.1 Power Exhaust 1 Test On/Off
PE.2 Power Exhaust 2 Test On/Off
ALRM Alarm Relay Test On/Off
CCH Crankcase Heat Test On/Off

FANS SUPPLY Te st Fan s

IDF VFD Power Test On/Off
F.SPD Indoor Fan Speed Test 0 to 100%
OFC.1 Outdoor Fan Relay Test On/Off

COOL Test Cooling

CTLR DigScrollCtrlPwrTest On/Off
CAPC Compressor Capacity Test 0 to 100%
F.SPD Cool Test Fan Speed 0 to 100%

HEAT Test Heating

HT.1 Heat Stage 1 Test On/Off
HT.2 Heat Stage 2 Test On/Off

EXPANDED NAME VALUES

Field Service Test Mode On/Off

THIRD PARTY CONTROL

Third party controls may interface with the unit ComfortLinkt
controls through the connections described below. See other
sections of these instructions for more information on the related
unit control and configurations.

Remote Occupancy

The remote occupancy input is provided on the field connection
terminal board (TB1). The Remote Occupancy Switch
configuration, Configuration→UNIT→RM.SW, identifies the
normally open or normally closed status of this input when
unoccupied.

S 5 = 24 VAC signal input
S 6 = 24 VAC source for dry contact

Fire Shutdown

The fire shutdown input is provided for unit shutdown in response
to a fire alarm or smoke detector. The Fire Shutdown Switch
configuration, Configuration→UNIT→FS.SW, identifies the
normally open or normally closed status of this input when there is
no fire alarm.

Input at field connection terminal board (TB1)

S Fire Shutdown 1 = 24 VAC source for dry contact
S Fire Shutdown 2 = 24 VAC signal input

Alarm Output

The alarm output is provided on the field connection terminal
board (TB1) to indicate a current alarm status. The output will be
24VAC if a current alarm exists.

S C=24VACcommon
S X = 24 VAC signal output

Economizer Monitoring

On field terminal board (TB1), terminals 8, 9, and 10 can be used
to monitor economizer position from a third party control system.
See economizer operation section for additional information.

In digital mode (E.CTL = 1 or 2), the economizer commanded
position can be read as a 2--10v or 4--20mA signal. TB1--8 and
TB1--9 are used as follows:

S To read a 2--10v signal, disconnect the violet wire on

TB1--J10--8 and place volt meter device across TB1--8 and

TB1--9.

S To read a 4--20mA signal, disconnect the violet wire on

TB1--J10--8 and the 500Ω resister at TB1--J10--6. Place amp

meter device between TB1--8 and TB1--9.

In analog mode (E.CTL = 3), the economizer position can be read
as a 2--10v feedback signal across TB1 -- 10 and TB1--9 at any time.

IMPORTANT: The violet wire and 500Ω resister must be
connected at the J10 connector as originally wired to operate the
economizer in analog mode.

Economizer Damper Control

For units with the economizer option or accessory and the ECB
control board, the damper position can be directly controlled
through the IAQ sensor input provided on the field connection
terminal board. The IAQ Analog Input configuration,
Configuration→AIR.Q→IA.CF will have to set to 3 (Control
Minimum Position). When IA.CF = 3, an external 4 to 20 mA
source is used to move the damper 0% to 100% directly.

Terminal 2 = 4-- 20mA + signal
Terminal 3 = 4-- 20mA -- common

IMPORTANT: In this mode preset minimum positions
configurations are not valid. The damper position may exceed the
input position to provide economizer cooling and CO

sensor input

2

can not be used for DCV control. Refer to the Indoor Air Quality
operation section for more information.

CONTROLS OPERATION

Display Configuration

The Configuration→DISP submenu is used to configure the local
display settings.

Metric Display (METR)

This variable is used to change the display from English units to
Metric units.

Language Selection (LANG)

This variable is used to change the language of the ComfortLink
display. At this time, only English is available.

48/50PD

11

Password Enable (PROT)

This variable enables or disables the use of a password. The
password is used to restrict use of the control to change
configurations.

Service Password (PSWD)

This variable is the 4-digit numeric password that is required if
enabled.

Test Display LEDs (TEST)

This is used to test the operation of the ComfortLinkt display.

Modes

The ComfortLink controls operate under a hierarchy of command
structure as defined by four main elements: the System Mode, the
HVAC Mode, the Occupied status, and the Unit Control Type.

The System Mode is the top level that defines three main states of
the control system: Disabled, Enabled, or Test.

The HVAC Mode is the next level that defines four main states of
functional operation: Disabled, Fan Only, Cool, and Heat.

The Occupied status affects set points for cooling and heating in
Space Sensor control mode and operation of the economizer for

48/50PD

indoor air quality ventilation and free cooling.
The general operating mode of the control and the status of some

related operation lockouts are located on the display at two
locations: Run Status→ MODE and Operating Modes→ MODE.

System Mode (SYS)

In Run Status and Operating Modes, the current system mode is
displayed with expandable text. This is an overall state of the unit.
Three states are: Unit Operation Disabled, Unit Operation Enabled,
or Service Test Enabled.

HVAC Mode (HVAC)

In Run Status and Operating Modes, the current allowed HVAC
mode is displayed with expandable text. This is the mode the unit
decides to run in based on its inputs. There are four main HVAC
modes; cooling has three different expanded texts. These modes
are shown below.

HVAC

Mode

Disabled HVAC Operation

Fan Only Ventilation

Cooling

Heating Heating Heating mode

Expanded Text Brief Description

Disabled

(fan--only)
Cooling Mechanical cooling
Free Cooling Only economizer used for cooling
Unoccupied Free

Cooling

Unit is in test mode or System mode is
disabled

Fan may run for ventilation

Only economizer use for cooling
(occupied coo ling set point active)

Remote HV AC Mode Disabled (HV.DN)

Allow disabling of HVAC mode. This is only available on a
network connection.

Cool Setpoint in Effect (EFF.C)

This shows the actual setpoint that is being used for control during
cooling mode.

Heat Setpoint in Effect (EFF.H)

This shows the actual setpoint that is being used for control during
heating mode.

Currently Occupied (OCC)

Displays the current state of assumed space occupancy based on
unit configuration and inputs.

Timed Override in Effect (T.OVR)

Displays if the state of occupancy is currently occupied due to an
override.

Linkage Active (LINK)

Displays if Linkage communication is established between the unit
and a Linkage source.

IMPORTANT: The 48/50PD unit only supports the Gen III
TEMP Monitor Thermostat.

Demand Limit in Effect (D.LMT)

Displays if a demand limit has been placed on the unit’s capacity.

Circuit OAT Lockout (C.LOC)

Displays if one or more refrigerant circuits operation is prevented
due to outdoor temperature limit lockout.

Heat OAT Lockout (H.LOC)

Displays if heating operation is prevented due to outdoor
temperature limit lockout.

Econo Cool OAT Lockout (E.LOC)

Displays if economizer operation for cooling is prevented due to
outdoor temperature limit lockout.

Unit Configuration

Many configurations that indicate what factory options and/or field
accessories are installed and other common operation variables are
included in Unit Configuration (Configuration→UNIT).
Configuration will be done at the factory for any factory-installed
option (FIOP).

Start--Up Delay (S.DLY)

This configuration sets the control start-up delay after the power is
interrupted. This can be used to stagger the start-up of multiple
units.

FanOnWhenOccupied(OC.FN)

A YES value will operate the indoor fan whenever the unit is in the
Occupied mode. A NO value will operate the indoor fan only when
heating or cooling is necessary. The factory default value is YES.

Shut Down on IDF Failure (IDF.F)

This configuration applies only if a fan switch is installed and
configured. A YES value will enable diagnostic Alert T409 to shut
down the unit when incorrect fan status is sensed. A NO value will
still permit Alert T409 but will not cause unit shutdown. The
factory default value is YES.

Supply Fan Maximum Speed (FS.MX)

This configuration sets the limit for the highest speed the fan can
run out of 100%. This max speed limit applies to the unit at all
times except for fan test.

Supply Fan Minimum Speed (FS.MN)

This configuration sets the limit for the lowest speed the fan can
run out of 100%. This minimum speed limit applies to the unit
during cooling mode and cooling test.

Vent Mode Fan Speed (FS.VM)

This configuration sets the speed the fan will run during the
ventilation mode. The fan speed does not vary during ventilation
so it will remain at this speed throughout vent mode.

Fan Status Switch (FN.SW)

This configuration identifies if a fan status switch is installed, and
what status (normally open, normally closed) the input is when the
indoor fan is OFF.

Filter Status Switch (FL.SW)

This configuration identifies if a filter status switch is installed, and
what status (normally open, normally closed) the input is when the
filter is CLEAN.

Fire Shutdown Switch (FS.SW)

This configuration identifies if a fire shutdown switch is installed,
and what status (normally open, normally closed) the input is when
the fire or smoke alarm is OFF (no alarm).

Remote Occupancy Switch (RM.SW)

This configuration identifies if a remote occupancy switch is
installed, and what status (normally open, normally closed) the
input is when UNOCCUPIED.

12

RH Sensor On OAQ Input (RH.S)

This configuration identifies if a space relative humidity sensor is
installed on the outdoor air quality (OAQ) input. A YES value
enables SP.RH display. A NO value disables SP.RH display and
use.

Space Humidity Switch (RH.SW)

This configuration identifies if a space relative humidity switch is
installed on the ENTHALPY input, and what status (normally
open, normally closed) the input is when the space humidity is
LOW.

Temperature Compensated Start Cooling Factor
(TCS.C)

This factor is used in the equation of the Temperature
Compensated Start Time Bias for cooling. A setting of 0 minutes
indicates Temperature Compensated Start in Cooling is not
permitted.

Temperature Compensated Start Heating Factor
(TCS.H)

This factor is used in the equation of the Temperature
Compensated Start Time Bias for heating. A setting of 0 minutes
indicates Temperature Compensated Start in Heating is not
permitted.

General Operating Sequence

The PD unit must be connected to a space temperature sensor
T--55, T--56, T58 or T59 and will not operate with a conventional
R, Y1, Y2, W1, W2, G, C thermostat. When a T--55, T--56, T58 or
T59 space temperature sensor is connected to the low voltage
terminal board as shown in the Installation Instructions Manual, the
PD unit will try to maintain the Space Temperature
(Temperatures→AIR.T→SPT) at one of four set points: The
Occupied Cool Set Point (Setpoints→OCSP), the Unoccupied
Cool Set Point (Setpoints→UCSP), Occupied Heat Set Point
(Setpoints→OHSP), or the Unoccupied Heat Set Point
(Setpoints→UHSP).

Occupancy Determination

When the building is in occupied mode, the occupied set points are
active. When the building is in unoccupied mode, the unoccupied
set points are active. The PD control will switch automatically
between cooling and heating to maintain temperature. However, to
minimize unnecessary cool to heat and heat to cool changes, there
is a 10--minute delay after the last stage turns off before the control
will switch modes. The heating and cooling set points are also
separated by a Heat--Cool Set Point Gap (Setpoints→GAP)thatis
user configurable from 2 to 10 degrees F. This parameter prevents
the unit from over cooling the conditioned space to where heating
mode is required or over heating the conditioned space to where
cooling mode is required.

The T55 space temperature sensor senses the temperature in the
conditioned space with no provisions for adjusting the space
temperature set point at the sensor. The T--56 space temperature
sensor senses the temperature in the conditioned space and allows
for adjustment of the space temperature set point by a configurable
number of degrees F higher or a configurable number of degrees F
lower at the space temperature sensor. The T58 space temperature
sensor communicates with the PD unit control board through a
CCN RS--485 +, -- , and ground connection. The T59 space
temperature sensor is a T56 sensor with an integrated temperature
display. A jumper wire is not needed between R and W1 when
using space temperature sensors T55, T56, T58 or T59.

The building’s occupancy is affected by a number of different
factors. When the unit is operating with a space temperature sensor
(T--55, T-- 56, T--58 or T--59), occupancy affects the unit set points
and the operation of the economizer. The factors affecting
occupancy are listed below from highest to lowest priority.

Level 1 Priority

The CCN point OCCUPIED is forced via an external device such
as a ComfortIDt controller: when OCCUPIED is forced to YES,
the unit is considered occupied, when OCCUPIED is forced to
NO, the unit is considered unoccupied. If OCCUPIED is not being
forced, proceed to the level 2 priority.

Level 2 Priority

Remote Occupancy Switch should be configured to either
Normally Open or Normally Closed when the user would like to
control the occupancy with an external switch. This switch is
field-- supplied (24v, single pole, single throw [SPST]). There are
three possible configurations for the remote occupancy switch:

1. (Configuration→UNIT→RM.SW = 0) No Switch

2. (Configuration→UNIT→RM.SW = 1) Normally Open

Switch

3. (Configuration→UNIT→RM.SW = 2) Normally Closed

Switch

If the switch is configured to No Switch (0), the switch input value
will be ignored and software will proceed to level 3 priority. For
each type of switch, the appropriate configuration and states are
listed in the table below.

TYPE OF SWITCH

Occupied when

Closed or

Unoccupied when

Open

Occupied when Open Normal Closed (2)

Unoccupied when

Closed

SWITCH

CONFIGURATION

Normal Open (1)

Normal Closed (2)

STATE OF

SWITCH AND

STATE OF

OCCUPANCY

Open and

Unoccupied

Closed and

Occupied

Open and
Occupied

Closed and

Occupied

IMPORTANT: To perform remote occupancy, an Economizer
Control Board must be installed in the unit.

Level 3 Priority

The following occupancy options are determined by the state of
Occupancy Schedule Number
(Configuration→CCN→SCH.O→SCH.N) and the Global
Schedule Broadcast (Configuration→CCN→BROD→B.GS).

1. (Configuration→CCN→SCH.O→SCH.N = 0) The unit is

always considered occupied and the programmed schedule
is ignored. This is the factory default.

2. (Configuration→CCN→SCH.O→SCH.N = 1- 64) Follow

the local programmed schedule. Schedules 1 to 64 are local
within the controller. The 48/50PD unit can only store one
local schedule and therefore changing this number only
changes the title of the schedule table.

3. (Configuration→CCN→SCH.O→SCH.N = 65- 99)

Follow the global programmed schedule. If the 48/50PD
unit is configured as a Global Schedule Broadcaster
(Configuration→CCN→ROD→B.GS = YES), the unit
will follow the unit’s programmed schedule and broadcast
the schedule so that other devices programmed to follow
this schedule number can receive the schedule. If the
48/50PD unit is not programmed as a Global Schedule
Broadcaster
(Configuration→CCN→BROD→B.GS = NO), the unit
will receive broadcasted schedules from the unit
programmed to broadcast this schedule number. While
using the programmed schedule, occupancy can be
temporarily switched from unoccupied to occupied by
pressing the override button for approximately 3 seconds on
the T--55, T-- 56, T -- 58 or T --59 space temperature sensor.
Override will only occur if SPT Override Enabled

48/50PD

13

(Configuration→CCN→SCH.O→OV.SP) is set to YES.
The length of the override period is determined by the
Timed Override Hours setting
(Configuration→CCN→SCH.O→OV>EX).

Compressor Operation

The 48/50 PD units use a Copeland Digital Scroll Compressor that
can vary the refrigerant capacity between 100 and 15%. This is
accomplished by a mechanism in the compressor that separates the
two scroll spirals which stops the pumping of the refrigerant gas.
This mechanism is operated by the differential pressure between
the suction and discharge of the compressor. The pressure to
operate the unloading mechanism is controlled by a small solenoid
situated in a refrigerant line between the top of the compressor and
the suction line. When the solenoid is energized the compressor is
unloaded. The solenoid coil is controlled by the Copeland Digital
Scroll Controller (DSC) that operates on a 1 to 5V signal from the
ComfortLink Auxiliary Board (AUX1) and converts this into a
Pulse Width Modulated (PWM) signal to the solenoid valve. The
pulse width modulated signal is an on and off signal that repeats
every 15 seconds with the off time portion of the 15 seconds
representing the % loading of the compressor.

48/50PD

The Compressor Capacity (Outputs→COOL→CAPC) can be
monitored on the ComfortLink Scrolling Marquee Display. The
Compressor Capacity value is determined by a Proportional,
Integral, Derivative (PID) algorithm that controls the Supply Air
Temperature (Temperatures→AIR.T→SAT) to the Supply Air
Control Point (Run Status→COOL→SA.CP).

The Compressor Minimum Capacity
(Configuration→COOL→MIN.C) is configured at the factory to
70%. This is the minimum compressor capacity that gives the
highest SEER rating for a 48 series unit with the highest gas heat
option and no economizer per AHRI standard 210/240. Since the
AHRI rating standard does not account for energy savings that can
be realized by displacement ventilation air distribution system and
extending economizer cooling operation at higher supply air
temperature set points, a complete energy analysis should be
conducted before changing the Compressor Minimum Capacity
(Configuration→COOL→MIN.C) setting to determine the energy
savings at a lower Compressor Minimum Capacity
(Configuration→COOL→MIN.C) setting.

Indoor Fan Operation

The indoor fan is controlled by the Indoor Fan VFD Power Relay
(Outputs→FANS→IDF) on the MBB (main base board) control,
which then operates the indoor fan contactor (IFC). On the
48/50PD units the Indoor Fan VFD Power Relay
(Outputs→FANS→IDF) is always on so that power is supplied to
the VFD electronic boards. This prevents the formation of
condensation on the VFD electronic boards and provides power to
the remote VFD display so that error codes and VFD configuration
parameters can be verified.

The 48/50PD unit controls require an accurate supply duct CFM at
the unit design point where the indoor fan will run at the Supply
Fan Maximum Speed (Configuration→UNIT→FS.MX).The
Supply Fan Maximum Speed (Configuration→UNIT→FS.MX)
is used for operation of the economizer and power exhaust. The
supply duct CFM is configured by the Indoor Fan Max Speed
CFM (Configuration→ECON→IDF .C). Default values for
Indoor Fan Max Speed CFM (Configuration→ECON→IDF.C)
are at 400 CFM per ton or 1600 CFM for the 05 size and 2000
CFM for the 06 size. It is preferred to use the supply duct CFM
from an air balance report to configure the Indoor Fan Max Speed
CFM (Configuration→ECON→IDF.C). If an air balance report
is not available then use the fan tables supplied in this book to
determine Fan Max Speed CFM
(Configuration→ECON→IDF.C). When using the fan tables to
determine Fan Max Speed CFM

(Configuration→ECON→IDF.C) set Economizer Position Test

(Service Test→INDP→ECON) to 0 (Economizer Damper Closed)
and Indoor Fan Speed Test (Service Tes→FAN S →F. S P D ) equal to
(Configuration→UNIT→FS.MX). Measure the supply to return

duct static pressure difference and indoor fan RPM. Make
correction to static pressure for all options installed in the unit per
the accessory pressure drop table. Determine Indoor Fan Max
Speed CFM (Configuration→ECON→IDF.C)
where the corrected static pressure and RPM cross.

The supply fan speed range is configured by the Supply Fan
Maximum Speed (Configuration→UNIT→FS.MX) and the
Supply Fan Minimum Speed (Configuration→UNIT→FS.MN).
These configuration values are in units of % speed referenced to a
2 to 10VDC signal to the VFD AI1 input with 2VDC representing
0% speed and 10VDC representing 100% speed or 0 to 60HZ
VFD frequency output to the motor.

The Supply Fan Minimum Speed
(Configuration→UNIT→FS.MN) can be user configured
between 10 and 70%. The Supply Fan Minimum Speed default
value is 70%, this provides the greatest energy efficiency rating for
a unit without an economizer in a mixed air type duct application.

The Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) can be configured between 80
and 100%. The Supply Fan Maximum Speed default value is
100%. Set the indoor fan pulley to the application design point
CFM for heating and cooling at 100% fan speed so that the CFM is
not lower than the minimum CFM allowed in the product data. If
the exact CFM can not be set by the half turn pulley settings then
adjust the Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) to fine tune the CFM to the
application requirements. The Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) RPM must now produce
supply CFM that is not lower that the minimum CFM allowed in
the product data for heating and cooling.

The indoor fan may operate during cooling with compressors
mode, free cooling with outdoor air mode, heating mode, or for
ventilation with outdoor air mode.

The indoor fan operation can be affected by the following:

S FanOnWhenOccupied(Configuration→UNIT→OC.FN)
S IAQ Analog Fan Config (Configuration→AIR.Q→IA.FN)
S IAQ Switch Fan Config (Configuration→AIR.Q→II.FN)
S Fan Status Switch (Configuration→UNIT→FN.SW)

When the unit is in occupied or unoccupied cooling mode the
supply fan will modulate to maintain the space temperature sensor
set point between the configured Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) and the Supply Fan Minimum
Speed (Configuration

When the 40PD or 50 PD unit is in occupied or unoccupied
heating mode (gas heat or electric heat mode) the indoor fan will
operate at the Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) setting.

For 48PD gas heating units, the IGC control fan output is also
monitored by the MBB control. This can result in additional
modifications of fan delays or other operation due to safety
functions of the IGC control.

When the PD unit is in free cooling mode the indoor fan will
modulate to maintain The Occupied Cool Set Point

(Setpoints→OCSP), the Unoccupied Cool Set Point
(Setpoints→UCSP), Occupied Heat Set Point
(Setpoints→OHSP), or the Unoccupied Heat Set Point
(Setpoints→UHSP).

When the PD unit is in ventilation mode and Fan On When
Occupied (Configuration→UNIT→OC.FN) the indoor fan will
operate at the Vent Mode Fan Speed

(Configuration→UNIT→FS.VM). Vent Mode Fan Speed
(Configuration→UNIT→FS.VM) factory default is 50% and can

be user configured between 40 and 100%.

→UNIT→FS.MN).

on the fan table

14

Outdoor Fan Operation

The 48/50 PD units use a multi--speed outdoor fan motor to control
the head pressure within an acceptable range at low outdoor
ambient temperatures. On the 48 and 50 PD--05 and 06 size units
the outdoor fan contactor is powered on the load side of the
compressor contactor so the outdoor fans will run only when the
compressor contactor is energized. When the outdoor fan
contactor is not energized the outdoor fan runs at high speed.

When the outdoor fan contactor is energized the outdoor fan runs
at low speed.

The outdoor fan speed is controlled by a system three of fan levels
set up in the control software. Table 6 shows the three levels and
fan speeds for each level. The fan levels are determined by
Outdoor Air Temperature (Temperatures→AIR.T→OAT) but can
be overridden by Condenser Pressure A (Pressures→SCP.A)
inputs to the Main Base Board.

FAN

LEVEL

0 OFF N/A

1 LOW 1. Compressor Contactor is OFF

2 HIGH

FAN

SPEED

CONDITIONS TO TRANSITION TO NEXT

LOWER LEVEL

1 . O u t s i d e A i r Te m p e r a t u r e C o n t r o l --- --- F a n
Lev2 Off Temperature 45 F or below (Confi-

guration→COOL→OFC→2.OFF <=45F)*

2. Condenser Pressure A Override --- --- Fan
Lev2 Min Pressure 200 psig or below (Config-

uration→COOL→OFC→2.MNP<= 200 psig)*

CONDITIONS TO TRANSITION TO NEXT

HIGHER LEVEL

1. Compressor Contactor is ON

(on initial start up outdoor fan runs at Level 2 for
10 seconds before moving to correct level based
on outside air temperature or Condenser Pres­sure A)

1. Outside Air Temperature Control — Fan
Lev2 On Temperature 55 F or above (Configu-

ration→COOL→OFC→2.ON >=55F)*

2. Condenser Pressure A Override — Fan
Lev1 Max Pressure 450 psig or above (Config-

uration→COOL→OFC→1.MXP>= 450 psig)*

N/A

Table 6 — Fan Level Control of Outdoor Fan

*Configuration parameters 1.MXP, 2.MNP, 2.ON and 2.OFF factory default configuration should not be changed. The default configurations have been qualified over a wide
range of conditions and are provided in case a field replacement of the control board o ccurs and the settings need to be check ed or manually conf igured.\

Economizer Operation

If an economizer is installed, then Economizer Installed
(Configuration→UNIT→EC.EN) should be set to YES. The
economizer is controlled by the Econo Commanded Position
(Outputs→ECON→EC.CP) on the Economizer Control Board
(ECB). Feed back from the economizer actuator is output on
configuration parameter Econo Actual Position
(Outputs→ECON→EC.AP).

Economizer Actuator

The economizer actuator used with the 48/50PD units is a
Multi--Function Technology (MFT) actuator. This allows the
ComfortLink system to communicate with the actuator through a
feedback signal. The configuration Economizer Control Type
(Configuration→ECON→E.CTL) determines the communication
method, either digital or analog, used to communicate between the
Economizer Control Board and the economizer actuator.

The power to the unit must be cycled after the Economizer Control
Type (Configuration →ECON→E.CTL) configuration parameter
is changed.

E.CTL = 1 or 2 (Digital/Position or Digital/Command)

When Economizer Control Type
(Configuration→ECON→E.CTL) is set to 1, the Economizer
Control Board will communicate with the economizer actuator
using the digital protocol, from Economizer Control Board plug
J7--1 to actuator pin 5. The commanded position and the actuators
actual position are communicated back and forth between the
actuator and the Economizer Control Board. When the Economizer
Control Board and actuator first initiate communication, a Control
Angle Economizer Control Type (Operating Modes→
ECON→C.ANG) is provided to the Economizer Control Board
and defines the actuator’s range of motion. The control angle must
be greater than the Min Actuator Ctrl Angle
(Configuration→ECON→M.ANG). During this digital control,
the Economizer Control Board analog 4 to 20 mA output will
represent the actuator’s actual position when E.CTL = 1 or

Communication

commanded position when E.CTL = 2. Because the wiring has a
built--in 500 -- ohm resistor, the 4 to 20mA signal is converted to a 2
to 10VDC signal that is accessible via a field connected terminal
board TB--8 and TB-- 9. However, before this signal can be read
remotely, the violet wire that connects the actuator to field
connection terminal board TB--J10--8 must be removed or cut.

E.CTL = 3 (Analog Control)

When E.CTL is set to 3, the Economizer Control Board will NOT
communicate with the economizer actuator directly with the 4 to
20mA analog signal wired to TB--8 and TB -- 9 along with the
500--ohm resistor producing a 2 to 10VDC signal for the actuator.
While in this mode, the actuator’s built--in 2 to 10VDC feedback
signal s accessible via TB--9 and TB--10 any time because it is not
used by the Economizer Control Board.

Cooling

Free

The economizer will be allowed to help with cooling if the
Outdoor Air Temperature (Temperatures→AIR.T→OAT) is less
than the configured Econo Cool Hi Temp Limit
(Configuration→ECON→EH.LO) and greater than the
configured Econo Cool Lo Temp Limit
(Configuration→ECON→EL.LO). If an enthalpy sensor is
installed, the outdoor temperature must be below the Econo Cool
Hi Temp Limit (Configuration→ECON→EH.LO) and the
Outdoor Enthalpy Switch (Inputs→GEN.I→ENTH) must be
LOW.

Unoccupied Free Cooling

The unoccupied free cooling algorithm attempts to maintain the
building space half way between the Occupied Cool Set Point

(Setpoints→OCSP) and Occupied Heat Set Point
(Setpoints→OHSP) using only the economizer when the

conditions in the building and the outdoors are suitable., during
UNoccupied periods if the air in the building and the outdoor air
are suitable. Three different configurations define this algorithm:

1. Unoccupied Free Cooling

(Configuration→ECON→UEFC)

48/50PD

15

a. (Configuration→ECON→UEFC = 0) -- D i s a b l e d

When UEFC = 0, unoccupied free cooling is disabled.
Cooling will only occur if the space exceeds the
unoccupied setpoints.

b. (Configuration→ECON→UEFC = 1) -- Unoccupied

When UEFC is set to 1, unoccupied free cooling can
occur throughout the entire unoccupied period. The
space temperature must be higher then the mid--point
between the occupied cooling and heating set points.

c. (Configuration→ECON→UEFC = 2) -- Preoccupancy

When UEFC is set to 2, unoccupied free cooling can
only occur when the time until the next occupied period
is less than the Free Cool PreOcc Time (FC.TM) in
minutes.

2. Free Cool PreOcc Time

(Configuration→ECON→FC.TM)

FC.TM is the configuration that determines how many
minutes before occupancy that free cooling can occur when
set for Preoccupancy (UEFC = 2).

3. 1.Free Cool Low Temp Limit

(Configuration→ECON→FC.LO)

48/50PD

Unoccupied free cooling cannot occur if the Outdoor Air
Temperature (Temperature→ AIR.T→ OAT) is less than
FC.LO.

Exhaust

Power

To enable power exhaust set Power Exhaust Installed
(Configuration→ECON→PE.EN) to YES. On the 48/50PD--05
and 06 size units both power exhaust fans are wired together and
are controlled by the configuration Power Exhaust Stage1 CFM
(Configuration→ECON→PE1.C). When the Indoor Fan Max
Speed CFM (Configuration→ECON→IDF.C) is set to the correct
supply duct CFM (either by fan tables or air balance report) the
control will calculate the outside air CFM based on outside air
damper position and Commanded Fan Speed
(Outputs→FANS→F. S P D ) to turn on the power exhaust when the
calculated outside air CFM reaches Power Exhaust Stage1 CFM
(Configuration→ECON→PE1.C). The power exhaust will turn
off when the calculated outside air CFM falls below Power
Exhaust Stage1 CFM (Configuration→ECON→PE1.C).The
Power Exhaust Stage2 CFM (Configuration→ECON→PE2.C) is
not currently used on the 48/50PD--05 and 06 units.

Indoor Air Quality (IAQ)

The ComfortLink TM control has the capability for several
methods of demand ventilation control. Indoor air quality is
typically measured using a CO2 sensor whose measurements are
displayed in parts per million (ppm). Outdoor air quality may be
measured with a CO2 sensor for indoor--outdoor differential
demand ventilation control, or with other sensor types for the
outdoor air lockout function. The factory--installed indoor air
quality CO2 sensor is mounted in the return section. A
field-- installed indoor air quality CO2 sensor may be mounted in
the return or directly in the occupied space, per job requirements.
The indoor air quality modes of operation can be affected by the
IAQ Analog Input Config (Configuration→ AIR.Q→ IA.CF),
IAQ Switch Input Config (Configuration→ AIR.Q→ IA.CF),
OAQ Analog Input Config (Configuration→ AIR.Q→ OA.CF)
and other related fan and limit configurations as described below.

IAQ (Analog

The ComfortLink TM control is configured for indoor air quality
sensors which provide 4 to 20 mA signal for 0 to 2000 ppm CO2.
If the sensor being used has a different range, the ppm display
range must be reconfigured by entering new values for the IAQ
Sensor Value at 4mA (Configuration→AIR.Q→I.4M) and IAQ
Sensor Value at 20mA (Configuration→AIR.Q→I.20M).

IA.CF = 0 (No IAQ)

IA.CF = 0 signifies that there is no IAQ sensor installed. The
damper will operate at the Econ Min at Max Fan Speed

Input)

(Configuration→ECON→MP.MX) when the fan is at Supply Fan
Maximum Speed (Configuration→UNIT→FS.MX) and the
damper position will vary at other fan speeds as described in the
Cooling Mode with Economizer section below when the space is
occupied and the indoor fan is on.

IA.CF = 1 (DCV)

When IA.CF = 1 the IAQ algorithm is set for Demand Control
Ventilation (DCV). During DCV, the damper modulates between
two user configurations depending upon the relationship between
the Indoor Air Quality (IAQ) and the Outdoor Air Quality (OAQ).
The lower of these two positions is referred to as the Econo Min
IAQ Position (Configuration→AIR.Q→AQ.MN) while the higher
is referred to as the Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX). The Econo Min IAQ
Position (Configuration→AIR.Q→AQ.MN) should be set to an
economizer position that brings in enough fresh air to remove
contaminates and CO2 generated by sources other than people.
The Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) should be set to an
economizer position that brings in fresh air to remove contaminates
and CO2 generated by all sources including people when the
indoor fan is operating at the Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX). The Econ Min at Max Fan
Speed (Configuration→ECON→MP.MX) value is the design
value for maximum occupancy.

The ComfortLink TM control will begin to open the damper from
the Econo Min IAQ Position (Configuration→AIR.Q→AQ.MN)
position when the IAQ level begins to exceed the Outdoor Air
Quality (OAQ) level by a configurable amount. This amount is
referred to as AQ Differential Low
(Configuration→AIR.Q→AQD.L). When the differential
between IAQ and OAQ reaches AQ Differential High
(Configuration→AIR.Q→AQD.H), the economizer position will
be at the Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) when the indoor fan speed is
at Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX). When the IAQ/OAQ
differential is between AQ Differential Low

(Configuration→AIR.Q→AQD.L) and AQ Differential High
(Configuration→AIR.Q→AQD.H), the control will modulate the

damper between Econ Min at Max Fan Speed

(Configuration→ECON→MP.MX) and Econo Min IAQ Position
(Configuration→AIR.Q→AQ.MN) in a linear manner as shown

in Figure 3. At other fan speeds the economizer damper will
operate in the shaded area between the two economizer position
curves but at the actual fan speed as indicated by Commanded Fan
Speed (Outputs→FANS→F. S P D ) .

IA.CF = 2 (Override IAQ)

When IA.CF = 2, the IAQ algorithm maintains the damper at Econ
Min at Max Fan Speed (Configuration→ECON→MP.MX) wh en
the indoor fan speed is at Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) or in the shaded area of Figure
3 when the indoor fan speed is at the Commanded Fan Speed
(Outputs→FANS→F. S P D ) until the override condition triggers.
The override triggers when the IAQ/OAQ differential is greater
than AQ Differential High
The IAQ Override Position (Configuration→AIR.Q→OVR.P).
The economizer damper will return to the Econ Min at Max Fan
Speed (Configuration→ECON→MP.MX) or MP.MX curve at
other fan speeds when the IAQ/OAQ differential is less than the
AQ Differential Low (Configuration→AIR.Q→AQD.L).

The override algorithm will operate whenever the building is
occupied and the indoor fan is operating or whenever the IAQ
algorithm has caused the indoor fan to operate. The IAQ Analog
Fan Config (Configuration→AIR.Q→IA.FN) determines whether
or not the IAQ algorithm can turn on the indoor fan.

If the indoor fan is not operating, the economizer position will be
zero. If the override is not active and the building is unoccupied,
the economizer position will be zero. The damper position may

(Configuration→AIR.Q→AQD.H).

16

exceed Econ Min at Max Fan Speed

(Configuration→ECON→MP.MX) or IAQ Override Position
(Configuration→AIR.Q→OVR.P) to provide economizer

cooling.

IA.CF = 3 (Control Minimum Position)

When IA.CF = 3, an external 4 to 20 mA source is used to set the
minimum position. The 4mA signal corresponds to 0% and the 20
mA signal corresponds to 100%. In this mode, configuration such
as Econ Min at Max Fan Speed

(Configuration→ECON→MP.MX), Econo Min IAQ Position
(Configuration→AIR.Q→AQ.MN) and the economizer minimum

position and DCV minimum position curves in figure 3 are not
used.

If the indoor fan is not operating, the economizer position will be
zero. The damper position may exceed the economizer minimum
position to provide economizer cooling.

IAQ (Switch

Indoor air quality can also be measured using a switch input. For
the purpose of specifying the type of switch input, low CO2 levels
are considered normal. The IAQ switch input is defined by the
IAQ Switch Input Config (Configuration→AIR.Q→II.CF).
Enthalpy and IAQ are controlled by the same switch input and
therefore cannot be used simultaneously.

II.CF = 0 (NO IAQ)

The II.CF = 0, configuration signifies that there is no IAQ switch
input. The damper will operate at the Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) and corresponding damper
position curve based on indoor fan speed when the space is
occupied and the indoor fan is on.

II.CF = 1 (DCV Normally Open)
II.CF = 2 (DCV Normally Closed)

The Demand Control Ventilation (DCV) allows the economizer
minimum position to be decreased when there is no IAQ problem.
If IAQ is low, the economizer minimum position is Econo Min
IAQ Position (Configuration→AIR.Q→AQ.MN) when the indoor
fan is operating at Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX). If IAQ is high, the
economizer minimum position is Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) when the indoor fan is
operating at Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX).

II.CF = 3 (Override Normally Open)
II.CF = 4 (Override Normally Closed)

The damper override function permits absolute positioning of the
economizer damper for ventilation purposes. The override is
active when IAQ is high and inactive when IAQ is low. The
override position is configured by the IAQ Override Position
(Configuration→AIR.Q→OVR.P).

Outdoor Air Quality (Analog

The ComfortLink TM control is configured for outdoor air quality
sensors which provide a 4 to 20 mA signal corresponding to 0 to
2000 ppm CO2. If a field supplied sensor has a different range, the
ppm display range must be reconfigured by entering new values
for the OAQ Sensor Value at 4mA
(Configuration→AIR.Q→O.4M) and OAQ Sensor Value at
20mA (Configuration→AIR.Q→O.20M).

OA.CF = 0 (NO OAQ)

This signifies that there is no outdoor air sensor installed. The
default value of OAQ is 400 ppm CO2.

OA.CF = 1 (DCV)

The outdoor air quality sensor analog input is the value of OAQ.

OA.CF = 2 (OAQ Lockout)

The outdoor air quality analog input is only used to lock out the
outdoor ventilation. The economizer commanded position is set to
0% when the CO2 ppm exceeds the OAQ lockout value
configured for the OAQ Lockout Limit
(Configuration→AIR.Q→AQ.L). The default value for OAQ

Input)

Input)

Lockout Limit (Configuration→AIR.Q→OAQ.L) is 600 ppm
CO2.

Fan Enable (Analog IAQ

The DCV algorithm will operate whenever the building is
occupied and the indoor fan is operating or whenever the IAQ
algorithm has caused the indoor fan to operate. The IAQ Analog
Fan Config (Configuration→AIR.Q→IA.FN) determines
whether or not the IAQ algorithm can turn on the indoor fan. If the
indoor fan is not operating, the economizer position will be zero.
The damper position may exceed Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) and corresponding damper
position curve to provide economizer cooling.

IA.FN = 0 (Never)

When IA.FN =0, the IAQ algorithm can never turn on the fan.

IA.FN = 1 (Occupied)

When IA.FN =1, the IAQ algorithm will turn on the indoor fan
whenever the building is occupied and IAQ/OAQ differential is
greater than the Fan On AQ Differential
(Configuration→AIR.Q→DF.ON). The indoor fan will turn off
when the IAQ/OAQ differential is less than the Fan Off AQ
Differential (Configuration→AIR.Q→DF.OF).

IA.FN = 2 (Always)

The indoor fan operation for IA.FN =2,isthesameasthe
operation when IA.FN =1, except the algorithm is not limited to
the occupied periods only. The fan can be triggered on when the
space is occupied or unoccupied.

Fan Enable (Analog Switch

The DCV algorithm will operate whenever the building is
occupied and the indoor fan is operating or whenever the IAQ
algorithm has caused the indoor fan to operate. The IAQ Switch
Fan Config (Configuration→AIR.Q→II.FN) determines whether
or not the IAQ algorithm can turn on the indoor fan. If the indoor
fan is not operating, the economizer position will be zero. The
damper position may exceed Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) and corresponding damper
position curve to provide economizer cooling.

II.FN = 0 (Never)

When II.FN =0, the IAQ algorithm can never turn on the fan.

II.FN = 1 (Occupied)

When II.FN =1, the IAQ algorithm will turn on the indoor fan
whenever the building is occupied and IAQ is high. The indoor
fan will turn off when the IAQ returns to normal.

II.FN = 2 (Always)

The indoor fan operation for II.FN =2, is the same as the operation
when IA.FN =1, except the algorithm is not limited to the
occupied periods only. The fan can be triggered on when the space
is occupied or unoccupied.

Sensor)

Input)

Cooling Modes

Cooling Mode Using Space Temperature Sensor T55,
T56, T58 or T59

In cooling mode the PD control will maintain the Occupied Cool
Set Point (Setpoint→OCSP) or the Unoccupied Cool Set Point
(Setpoints→UCSP) by modulating the indoor fan speed to supply
more or less airflow to the conditioned space at the Supply Air
Temperature (Temperatures→AIR.T→SAT).

Cooling Supply Air Set

The Cool Supply Air Set Point (Setpoint→SASP)can be
configured between 45F and 75F. The compressor modulates to
maintain a Supply Air Temperature

(Temperatures→AIR.T→SAT)at the Cool Supply Air Set Point
(Setpoint→SASP).

Cooling Speed Demand W

When the temperature in the conditioned space is higher than the
Occupied Cool Set Point (Setpoints→OCSP) plus the Fan Speed
Control Demand (Configuration→COOL?FS.CD) configuration

Point

indow

48/50PD

17

variable or Unoccupied Cool Set Point (Setpoints→UCSP) plus
the Fan Speed Control Demand
(Configuration→COOL→FS.CD) configuration variable the
indoor fan will run at 100%. When the temperature in the
conditioned space is between the Occupied Cool Set Point

(Setpoints→OCSP) and Occupied Cool Set Point
(Setpoints→OCSP) plus the Fan Speed Control Demand
(Configuration→COOL→FS.CD) configuration variable the

indoor fan modulates to satisfy the Occupied Cool Set Point

(Setpoints→OCSP) or Unoccupied Cool Set Point
(Setpoints→UCSP). When the temperature in the conditioned

space falls to 0.5F below the Occupied Cool Set Point

(Setpoints→OCSP) or Unoccupied Cool Set Point
(Setpoints→UCSP) for 5 minutes the controls will run unit in

ventilation mode. See ventilation mode sequence of operation.

can be set to --10 and the SASP Maximum Reset Up
(Configuration→COOL→SAT→SA.MU) configuration variable
can be set to 0 giving the range of Cool Supply Air Set Point
(Setpoint→SASP) reset of +0 and --10 F.

In normal operation when the Space Temperature is within the
speed demand window the unit control will modulate the indoor
fan speed and supply air temperature along a defined curve to bring
the Space Temperature to Occupied or Unoccupied Cool Set Point.
Since this curve is independent of the conditioned space load the
control scheme will adapt to any load present in the conditioned
space by adjusting the fan speed and supply air temperature and
move the space temperature along the defined time temperature
curve to Occupied or Unoccupied Cool Set Point.

When the space temperature rises above the Occupied Cool Set
Point (Setpoints→OCSP) + Fan Speed Control Demand
(Configuration→COOL→FS.CD) for over 2 minutes or is outside
the speed demand window and there is some amount of SASP
Maximum Reset Down (Configuration→COOL?SAT→SA.MD)
configured the indoor fan will be locked at 100% and the unit
controls will subtract a calculated amount of temperature reset to
the Cool Supply Air Set Point (Setpoint

48/50PD

speed will be locked at 100% as long as reset is applied. The
Supply Air Temperature will now adjust to this new Supply Air

→SASP). The indoor fan

Control Point (Run Status→COOL→SA.CP). The controls will
continue to subtract a calculated amount of temperature reset
cumulatively to a value equal to the Supply Air Temperature Set

C09143

Fig. 6 -- Cooling Speed Demand Window

Cooling Supply Air Set Point

Reset

The PD unit can be configured to allow for reset of the Cool
Supply Air Set Point (Setpoint→SASP). This is needed for
applications where a high Cool Supply Air Set Point
(Setpoint→SASP) is required or where dramatic load changes
occur over short time periods. In these situations a high supply air
temperature may not provide enough cooling to reduce the Space

Point (Setpoint→SASP) + SASP Maximum Reset Down
(Configuration→COOL→SAT→SA.MD). When the reset is no
longer needed the control will remove Down Reset until all reset is
removed and the Supply Air Control Point (Run
Status→COOL→SA.CP) is back to the original Supply Air Set
Point (Setpoint→SASP). The indoor fan will then modulate lower
than 100% to move the Space Temperature (Temperatures→SPT)
along the defined time temperature curve to Cool Supply Air Set
Point (Setpoint→SASP) or Unoccupied Cool Set Point
(Setpoints→UCSP). See Fig. 6 and 7.

Temperature (Temperatures→AIR.T→SPT) to the Occupied Cool
Set Point (Setpoints→OCSP) or the Unoccupied Cool Set Point
(Setpoints→UCSP) over a reasonable time period.

The compressor or economizer operation supplying cooling to the
conditioned space controls to the Supply Air Control Point (Run

Status→COOL→SA.CP). The Supply Air Control Point (Run
Status→COOL→SA.CP) which is a calculated value that is equal

to the Cool Supply Air Set Point (Setpoint→SASP) plus the
calculated amount of reset required up to the values set by
configuration variables SASP Maximum Reset Down
(Configuration→COOL→SAT→SA.MD) and SASP Maximum
Reset Up (Configuration→COOL→SAT→SA.MU).

Reset of the Cool Supply Air Set Point (Setpoint→SASP) is

Fig. 7 -- Cool Supply Air Set Point

C09144

limited by the configuration variables SASP Maximum Reset
Down (Configuration→COOL→SAT→SA.MD) and SASP
Maximum Reset Up (Configuration→COOL→SAT→SA.MU).
The SASP Maximum Reset Down

(Configuration→COOL→SAT→SA.MD)

configuration variable

can be set from --20 to 0 F and will allow the Cool Supply Air Set
Point (Setpoint→SASP) to be reset to as much as 20 F below the
Cool Supply Air Set Point (Setpoint→SASP). The SASP
Maximum Reset Up (Configuration→COOL?SAT→SA.MU)
configuration variable can be set from 0 to 20 F and will allow the
Supply Air Temperature to be Reset to as much as 20 F above the
Cool Supply Air Set Point (Setpoint→SASP). The SASP
Maximum Reset Down (Configuration→COOL →SAT→SA.MD)
and SASP Maximum Reset Up
(Configuration→COOL→SAT→SA.MU) configuration variables
can be set independently and do not need to be equal values above

Cooling Mode with Economizer Using Space
Temperature Sensor T55, T56, T58 or T59

If an economizer is installed, the Economizer Installed
configuration (Configuration→ECON→ EC.EN) should be set to
YES. The economizer is controlled by the Econo Commanded
Position (Outputs→ECON→ EC.CP) on the Economizer Control
Board. If the indoor fan is off or the building is unoccupied, the
economizer position is zero.

When the space temperature is above the Occupied Cool Set Point
(Setpoints→OCSP) and the economizer is installed, configured
and working correctly the unit controls will always try to meet
space cooling demand using the economizer before turning on the
compressor. The economizer will provide free cooling when the
following outside air conditions are true.

and below the Cool Supply Air Set Point (Setpoint→SASP).For
example, the SASP Maximum Reset Down
(Configuration→COOL→SAT→?SA.MD) configuration variable

18

For all units with Economizers:

1. 1.The outdoor temperature is below the Econo Cool Hi
Temp Limit (Configuration→ECON→EH.LO) and above
the Econo Cool Lo Temp Limit
(Configuration→ECON→EL.LO).

For units with Enthalpy Control

2. 1.The outdoor enthalpy is low and the outdoor temperature
is below the Econo Cool Hi Temp Limit
(Configuration→ECON→EH.LO) and above the Econo
Cool Lo Temp Limit (Configuration→ECON→EL.LO).

If the conditions above are true and the economizer is available for
cooling the economizer outside air and return air dampers will
modulate to allow proportions of outside air and return air to mix
and produce a temperature equal to the Cool Supply Air Set Point
(Setpoint→SASP). If reset is applied to the Supply Air
Temperature Set Point (Setpoint→SASP) the dampers will control
to the Supply Air Control Point (Run Status→COOL→SA.CP).

If the conditions above are true but the economizer dampers are not
able to satisfy the Cool Supply Air Set Point (Setpoint→SASP)
with Reset (if applied), the compressor will turn on and modulate
to provide additional cooling to satisfy the Cool Supply Air Set
Point (Setpoint→SASP) with Reset if applied.

If the conditions above are not true, the economizer will move to a
user Configurable Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) where the minimum
economizer damper position is based on the Supply Fan Maximum
Speed (Configuration→UNIT→FS.MX). This is done to
maintain a constant airflow through the economizer by opening the
dampers more as the indoor fan speed is reduced or closing the
dampers more as the indoor fan speed increases.

The shape of the Economizer Minimum Position vs. Fan Speed
curve is determined by the configuration parameters: Econ Min at
25% Fan speed (Configuration→ECON→MP.25), Econ Min at
50% Fan speed (Configuration→ECON→MP.50), Econ Min at
75% Fan speed (Configuration→ECON→MP.75) and Econ Min
at Max Fan speed (Configuration→ECON→MP.MX).

The Econ Min at 25% Fan speed

(Configuration→ECON→MP.25), Econ Min at 50% Fan speed
(Configuration→ECON→MP.50) and Econ Min at 75% Fan

speed (Configuration→ECON→MP.75) damper positions are
calculated based on the Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) and Supply Fan Maximum
Speed (Configuration→UNIT→FS.MX).

The Econ Min at 25% Fan speed

(Configuration→ECON→MP.25), Econ Min at 50% Fan speed
(Configuration→ECON→MP.50) and Econ Min at 75% Fan

speed (Configuration→ECON→MP.75) damper position are user
configurable and can be determined by setting the fan speed at 25,
50 and 75% and determining the damper position required to
maintain the Econ Min at Max Fan Speed
(Configuration→ECON→MP.MX) Outside air CFM through the
economizer outside air dampers. The default calculations
programmed into the PD controls is based on a side shot
economizer at 400 CFM/TON Supply Air flow with negative 0.25

O pressure in the return duct.

in H

2

Econ Min at Max fan Speed (Configuration→UNIT→FS.MN) is
set by user based on minimum required outside air ventilation
CFM required for the application. This procedure would be the
same as if this were a CV unit with the unit running at the design
point CFM. This determines the minimum position amount of
outside air CFM required when the fan is running at maximum
speed.

Configure the Indoor Fan Max Speed CFM
(Configuration→ECON→IDF.C) either to the supply CFM
determined from the fan performance tables or air balance reports.
If using fan performance tables make corrections for all installed
accessory pressure loss and use measured RPM, power and static

pressure readings to determine the actual Indoor Fan Max Speed
CFM (Configuration→ECON→IDF.C).

ECON MIN

AT MAX

FANSPEED

POSITION

(MINP_MAX)

VENTILATION FOR PEOPLE

MINIMUM

IAQ

DAMPER

POSITION

(AQ. MN)

INCREASING VENTILATION

VENTILATION FOR SOURCES

100

AQ
DIFFERENTIAL
LOW (AQD.L)

700

AQ
DIFFERENTIAL
HIGH (AQD.H)

INSIDE/OUTSIDE CO
DIFFERENTIAL

C09145

Fig. 8 -- Economizer Minimum Position

If the indoor fan is not operating, the economizer will be fully
closed, 0% open.

Ventilation

Mode

If the space temperature falls 0.5F below the Occupied Cool Set
Point (Setpoints→OCSP) the compressor will turn off, the indoor
fan speed will be set to the Vent Mode Fan Speed
(Configuration→UNIT→FS.VM) and the economizer will open
to the position that will supply minimum ventilation air at the
configured Vent Mode Fan Speed

(Configuration→UNIT→FS.VM). Default V ent Mode Fan Speed
(Configuration→UNIT→FS.VM) is 50%. Configuring the Vent

Mode Fan Speed (Configuration→UNIT→FS.VM) lower will
provide additional energy savings in vent mode but may not
supply the required ventilation air to the conditioned space at lower
fan speeds.

Demand Control V

The 48PD units can also be equipped with optional CO

entilation

sensors

2

for additional indoor air quality control. When unit is equipped
with a return duct CO
outside air CO

sensor the Economizer minimum position vs. fan

2

speed curve will be recalculated based on the CO

sensor or return duct CO2sensor and

2

level of the

2

return and/or outside air as shown in Fig. 8. See the Indoor Air

48/50PD

2

19

Quality (IAQ) section of the Economizer Operation section above
for more details on Demand Control Ventilation (DCV).

Economizer Operation for Units Equipped with Return
CO

Sensor Only

2

When the CO

(Inputs→AIR.Q→IAQ) below the AQ Differential Low
(Configuration→AIR.Q→AQD.L) value the MP.25, MP.50,

MP .75 and MP.MX points will be recalculated to new values for
MP .25, MP.50, MP.75 based on the Econ Min IAQ Position
(Configuration→AIR.Q→AQ.MN). The economizer outside air
damper will close and reduce the amount of outside air CFM to the
conditioned space based on the lower IAQ sensor readings and
indoor fan speed. The economizer outside air damper will
continue to close and reduce the amount of outside air CFM to the
conditioned space until the damper reaches user configurable Econ
Min IAQ Position (Configuration→AIR.Q→AQ.MN). This will
happen when the Commanded Fan Speed

(Outputs→FANS→F. S P D ) is at the Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX). When the Commanded Fan

Speed (Outputs→FANS→F. S P D ) is between Supply Fan
Maximum Speed (Configuration→UNIT→FS.MX) and the

48/50PD

Supply Fan Minimum Speed (Configuration→UNIT→FS.MN)
the damper will operate in the shaded area of Figure 8 based on the
IAQ Level (Inputs→AIR.Q→IAQ).

Economizer Operation for Units Equipped with Return
CO

Sensor and outside air CO2Sensor

2

The Economizer will operate similar to Economizer Operation for
Units Equipped with Return Air CO
Level (Inputs→AIR.Q→IAQ) will be determined by actual
outside air CO
value for OAQ.

sensor detects a CO2level or IAQ Level

2

Sensor Only but the IAQ

2

measurements instead of the 400 ppm CO2default

2

Air

Air

Cooling Mode Using Space Temperature Sensor T55,
T56, T58 or T59 and Humidistat (HL38MG029 or
TSTATCCPLH01--B)

Enhanced dehumidifying will be provided when a humidistat
(HL38MG029 or TSTATCCPLH01--B) is connected the PD unit
terminal strip across the R and W2 terminals (since the PD unit
does not support the use of conventional thermostat inputs the W2
terminal is reconfigured for humidity input) and Space Humidity
Switch (Configuration→UNIT→RH.SW) configuration variable
is set to 1 (Normally Open-- no call to dehumidify). Relative
humidity set point is set by adjusting the dial on the HL38MG029
or TSTATCCPLH01 --B device. When the humidistat contacts
close and provide 24VAC to the W2 terminal the PD unit will reset
the Supply Air Control Point (Run Status→COOL→SA.CP) by
one degree F lower than the Supply Air Set Point
(Setpoint→SASP) or the current control point if the Supply Air
Set Point (Setpoint→SASP) has already been modified. After 5
minutes if the humidistat contacts are still closed and 24 VAC is
being supplied to the W2 terminal the PD unit will reset the Supply
Air Control Point (Run Status→COOL→SA.CP) lower by one
more degree F. This reset cycle will continue to lower the supply
air temperature every 5 minutes until the Supply Air Control Point
(Run Status→COOL→SA.CP) is equal to the Supply Air Set
Point (Setpoint→SASP) + SASP Maximum Reset Down
(Configuration→COOL→SAT→SA.MD). The unit will continue
to operate at this reduced supply air temperature control point until
the humidistat contacts open and 24VAC is no longer supplied to
the W2 terminal. When 24VAC is no longer supplied to the W2
terminal the supply air control point will be reset higher by one
degree F. After 3 minutes if the humidistat contacts are still open
and 24VAC is not being supplied to the W2 terminal PD unit will
reset the Supply Air Control Point (Run Status→COOL→SA.CP)
higher by one more degree F. This reset cycle will continue to
raise the Supply Air Control Point (Run Status→COOL→SA.CP)
every 3 minutes until the Supply Air Control Point (Run

Status→COOL→SA.CP) is equal to the Supply Air Set Point
(Setpoint→SASP) or the supply air control point if reset was being

applied due to cooling requirements that reset the Supply Air Set
Point (Setpoint→SASP). Whenever Relative Humidity Reset is
applied the space temperature is controlled by modulating the fan
speed even if the fan was locked at 100% due to (Setpoint→
reset.

SASP)

Cooling Mode Using Space Temperature Sensor T55,
T56, or T58 and Humidity Sensor (HL39ZZ007 or
33ZCSENRH--01)

Enhanced dehumidifying will be provided when a humidly sensor
(HL39ZZ007 or 33ZCSENRH --01) 4 to 20 ma control is
connected the PD unit terminal strip across the TB1 -- J10 pin 3 and
4, power to humidity sensor is connected to R and C, the RH
Sensor on OAQ Input (Configuration→UNIT→RH.S) is set to
YES and Space Humidity Switch
(Configuration→UNIT→RH.SW) configuration variable is set to

0. Relative humidity set point is set by changing the value of
Space RH Set point (Setpoint→RH.SP). When the relative
humidity in the space is above the Space RH Set point
(Setpoint→RH.SP) the PD unit controls will reset the supply air
temperature by one degree F lower than the Supply Air Set Point
(Setpoint→SASP) or the current control point if the Supply Air
Set Point (Setpoint→SASP) has already been modified. After 5
minutes the PD unit will reset the Supply Air Control Point (Run
Status→COOL→SA.CP) lower by one more degree F. This reset
cycle will continue to lower the Supply Air Control Point (Run
Status→COOL→SA.CP) every 5 minutes until the Supply Air
Control Point (Run Status→COOL→SA.CP) is equal to the
Supply Air Set Point (Setpoint→SASP) +SASPMaximumReset
Down (Configuration→COOL→ SAT→SA.MD). When the
relative humidity in the space goes below the Space RH Set Point

(Setpoint→RH.SP) -- the Space RH Deadband
(Setpoint→RH.DB) the supply air control point will be reset

higher by one degree F. After 3 minutes if the humidity sensor
reading is still below the Space RH Set Point (Setpoint→RH.SP) --
the Space RH Deadband (Setpoint→RH.DB), the PD unit will
reset the Supply Air Control Point (Run

Status→COOL
cycle will continue to raise the Supply Air Control Point (Run
Status→COOL→SA.CP) every 3 minutes until the supply air

temperature control point is equal to the Supply Air Set Point
(Setpoint→SASP) or the supply air control point if reset was being
applied due to cooling requirements that reset the Supply Air Set
Point (Setpoint→SASP).

→SA.CP) higher by one more degree F. This reset

Heating Modes

Gas Heating Mode Using Space Temperature Sensor
T55, T56, or T58 (48PD Units Only)

For gas units, the Type of Heat Installed
(Configuration→HEAT→HT.TY) will be factory set to a value of

1.
Heat will not operate if the outdoor temperature is greater than the

value configured for the Heating Lockout Temperature

(Configuration→HEAT→HT.LO), Heat Minimum On Time
(Configuration→HEAT→MRT.H) and Heat Minimum Off Time
(Configuration→HEAT→MOT.H). Timeguards apply to both

stages of heating. Factory defaults values are 2 minute s ON and 2
minutes OFF. The Integrated Gas Controller (IGC) minimum
on--time of 1 minute will be followed even if Heat Minimum On
Time (Configuration→HEAT→MRT.H) is lower and during
Service Test.

If the indoor fan control is configured to cycle with the heating
demand by setting Fan ON When Occupied Heat Minimum On
Time (Configuration→UNIT→OC.FN) to NO, the fan will stop
after a delay configured by Fan--off Delay, Gas Heat
(Configuration→HEAT→FOD.G). The factory default for
Fan--off Delay, Gas Heat (Configuration→HEAT→FOD.G) is 45
seconds. If the IGC temperature limit switch opens within 10
minutes of the end of the gas heat cycle, the next fan off delay will

20

be extended by 15 seconds. The maximum delay is 3 minutes.
Once modified by the IGC, the fan off delay will not change back
to the configured Fan--off Delay, Gas Heat
(Configuration→HEAT→FOD.G) unless power is reset to the
control.

A light emitting diode (LED) is provided on the IGC to indicate
status. During normal operation the LED is continuously on. See
the Troubleshooting section if the LED is off or flashing. The IGC
is located behind the gas section access panel door. See Figure 8 or
9 for location.

The 48/50PD unit control will switch automatically between
cooling and heating to maintain space temperature. To minimize
unnecessary changes there is a 10 minute Mode Select Timeguard
(Operating Modes→HEAT→MS.TG) after the last stage of
cooling turns off and before the heating is allowed.

The unit tries to maintain the space temperature at the Occupied
Heat Setpoint (Setpoint→OHSP) or the Unoccupied Heat Setpoint
(Setpoint→UHSP). See the Occupancy Determination section for
factors that affect the Currently Occupied (Run

Status→VIEW→OCC) parameter. Heating Demand (Operating
Modes→HEAT→SPT→DMD.H) is equal to the occupied or
unoccupied set point minus the Space Temperature (Operating
Modes→HEAT→SPT→SPT) [DMD.H = Setpoint -- SPT].

Two methods are used to add and remove stages of heating for
48PD units. The first method causes the unit to operate around its
steady state number of stages. For example, if the correct number
of stages is between 0 and 1, this method will cause the first stage
to cycle. If the correct number of stages is between 1 and 2, this
method will cause the second stage to cycle. The second method
causes the unit to find the steady--state number of stages. Details of
these methods are provided below.

The control uses two methods to add a stage of heating. The first
method will add a stage of heating when the Heating Demand
(Operating Modes→HEAT→SPT→DMD.H) plus the change in
Spacetemp Trend (Operating Modes→HEAT→SPT→TRND)
times the Heat Thermal Lag Factor (Operating

Modes→HEAT→

SPT→H.LAG) is greater than the SPT Heat

Demand (+) Level (Operating Modes→HEAT→SPT→HT.PD)

[DMD.H + change TRND * H.LAG > HT.PD].
The second method will add a stage of heating when Heat Demand

(Operating Modes→HEAT→SPT→DMD.H) is greater that the
SPT Heat Demand (+) Level (Operating

Modes→HEAT→SPT→HT.PD) plus 0.5 degrees F [DMD.H >
HT.PD + 0.5] and the heat demand is changing at a rate greater

than 0.3 degrees F per minute.

The control uses two methods to remove a stage of heating. The
first method will remove a stage of heating when the Heating
Demand (Operating Modes→HEAT→SPT→DMD.H) plus the
change in Spacetemp Trend (Operating
Modes→HEAT→SPT→TRND) times the Heat Thermal Lag
Factor (Operating Modes→HEAT→SPT→H.LAG)islessthan
the SPT Heat Demand (--) Level (Operating

Modes→HEAT→SPT→HT.ND) [DMD.H + change TRND *
H.LAG < HT.ND].

The second method will remove a stage of heating when Heat
Demand (Operating Modes→HEAT→

SPT→DMD.H) is less that

the SPT Heat Demand (--) Level (Operating

Modes→HEAT→SPT→HT.ND) minus 0.5 degrees F [DMD.H <
HT.PD -- 0.5] and the heat demand is changing at a rate greater

than 0.3 degrees F per minute.
Configurable delays also apply when adding stages per Heat Stage

Increase Time (Configuration→HEAT→H.INC) or removing
stages per Heat Stage Decrease Time

(Configuration→HEAT→H.DEC). Heat Minimum On Time
(Configuration→HEAT→MRT.H) and Heat Minimum Off Time
(Configuration→HEAT→MOT.H) also apply.

Supply--Air Temperature Sensor (SA

T)

The SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) affects the Supply Air
Temperature (Temperatures→AIR.T→SAT) value displayed. This
configuration is accessible via the Scrolling Marquee on the SAT
Heat Mode Sensing (Configuration→HEAT→SAT→SAT.H).

When the SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) =DSBL, the Supply Air
Temperature (T emperatures→AIR.T→SAT) value on the
Scrolling Marquee and the CCN tables will be forced to zero when
heat outputs come ON and for 5 minutes after. The default Supply
Air Temperature (Temperatures→AIR.T→SAT) location is at the
fan inlet, upstream of the heat section.

When the SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) =ENBL, the Supply Air
Temperature (Temperatures→AIR.T→SAT) sensor reading is
displayed at the Scrolling Marquee and the CCN tables during
heating mode. This setting should only be used if the original SAT
sensor wires are removed from the Main Base Board (MBB) and
replaced by an accessory SAT sensor located in the supply duct
downstream of the heat section. There are then two supply air
temperature limits that become active, the Maximum SAT Lower
Level (Configuration→HEAT→SAT→SAM.L) the Maximum
SAT Upper Level (Configuration→HEAT→SAT→SAM.U).
Any time the supply air temperature rises above the Maximum
SAT Lower Level (Configuration→HEAT→SAT

→SAM.L) the

heat staging will be limited to what is currently on and no
additional stages can be added until the supply air temperature falls
below the Maximum SAT Lower Level
(Configuration→HEAT→SAT→SAM.L). If the supply air
temperature rises above the Maximum SAT Upper Level
(Configuration→HEAT→SAT→SAM.U), then heating will be
reduced by removing a heat stage. That stage can not be added
again until the Supply Air Temperature
(Temperatures→AIR.T→SAT) falls below the Maximum SAT
Lower Level (Configuration→HEAT→SAT→SAM.L).Ifthe
supply air temperature stays above the Maximum SAT Upper
Level (Configuration→HEAT→SAT→SAM.U), then another
stage will be removed after the Heat Stage Decrease Time
(Configuration→HEAT→H.DEC).

In heating mode the PD control will maintain the Occupied Heat
Set Point (Setpoint→OHSP) or the Unoccupied Heat Set Point
(Setpoint→UHSP) by turning on or off the Stage 1 and Stage 2
Gas Heat at the Supply Fan Minimum Speed
(Configuration→UNIT→FS.MN).

When the space temperature sensor detects the space temperature
below the Occupied Heat Set Point (Setpoint→OHSP) or
Unoccupied Heat Set Point (Setpoint→UHSP) and power is sent
to the Integrated Gas Unit Controller (IGC) board. The heat
staging is determined as described above and the Integrated Gas
Controller (IGC) initiates the gas heat module start-- up.

Gas Heat

Start--Up

An LED (light-emitting diode) on the IGC board will be on during
normal operation. A check is made to ensure that the rollout switch
and limit switch are closed and the induced--draft motor is running.
The induced-draft motor is then energized, and when speed is
proven with the Hall Effect sensor on the motor, the ignition
activation period begins. The burners will ignite within 5 seconds.
If the burners do not light, there is a 22-second delay before
another 5-second attempt. If the burners still do not light, this
sequence is repeated for 15 minutes. After the 15 minutes have
elapsed, if the burners still have not lit, heating is locked out.
When ignition occurs the IGC board will continue to monitor the
condition of the rollout and limit switches, the Hall Effect sensor,
as well as the flame sensor. If for some reason the over temperature
limit opens prior to the start of the indoor fan blower, on the next
attempt, the 45-second delay will be shortened to 5 seconds less
than the time from initiation of heat to when the limit tripped. Gas

48/50PD

21

will not be interrupted to the burners and heating will continue.
Once modified, the fan on delay will not change back to 45
seconds unless power is reset to the control. When the indoor fan
turns on after the 40 or 45 second delay the indoor fan will run at
100% fan speed.

Gas Heat

When additional heat is required, power is supplied to the second
stage of the main gas valve. When the space temperature is 0.5F
above the Occupied Heat Set Point (Setpoint→OHSP) or
Unoccupied Heat Set Point (Setpoint→UHSP) power is removed
from the second stage of the main gas valve and to the IGC W1
terminal. Both stage 1 and stage 2 of the gas valve closes,
interrupting the flow of gas to the main burners.

Gas Heat Shut

If power to the IGC W1 terminal lasted less than 1 minute, the
heating cycle will not terminate until 1 minute after power is
applied to the W1 terminal of the IGC board. If the over
temperature limit opens after the indoor motor is stopped within 10
minutes of W1 becoming inactive, on the next cycle the time will
be extended by 15 seconds. The maximum delay is 3 minutes.

48/50PD

Once modified, the fan off delay will not change back to 45
seconds unless power is reset to the control. A LED indicator is
provided on the IGC to monitor operation. The IGC is located in
the gas burner section and can be accessed by opening the gas
access door. During normal operation, the LED is continuously
on.

Gas Heat with

When there is a call for heat as described above the indoor fan will
operate at the Supply Fan Maximum Speed
(Configuration→UNIT→FS.MX) configuration setting and the
economizer outdoor air damper will move to the Econ Min at Max
Fan Speed (Configuration→ECON→MP.MX) position. The
economizer outdoor air damper is closed when the indoor fan is
not operating.

Staging

Down

Economizer

Electric Heating Mode Using Space Temperature
Sensor T55, T56, or T58 (50PD Units Only)

For electric heat units with factory installed electric heat, the Type
of Heat Installed (Configuration→HEAT→HT.TY) will be
factory set to a value of 2 and the Number of Heat Stages
(Configuration→HEAT→N.HTR) will be factory set to match the
installed heater. If electric heat is installed in the field the value for
Number of Heat Stages (Configuration→HEAT→N.HTR) must
be changed to match the number of heat stages installed.

Heat will not operate if the outdoor temperature is greater that the
value configured for the Heating Lockout Temperature

(Configuration→HEAT→HT.LO), Heat Minimum On Time
(Configuration→HEAT→MRT.H) and Heat Minimum Off Time
(Configuration→HEAT→MOT.H). Timeguards apply to both

stages of heating. Factory defaults values are 2 minute s ON and 2
minutes OFF.

If the indoor fan control is configured to cycle with the heating
demand by setting Fan ON When Occupied Heat Minimum On
Time (Configuration→UNIT→OC.FN) to NO, the fan will stop
after a delay configured by Fan--off Delay, Elect Heat
(Configuration→HEAT→FOD.E). The factory default for
Fan--off Delay, Elect Heat (Configuration→HEAT→FOD.E) is
30 seconds.

The electronic control uses information from the space sensor to
determine the number of heat stages required. Once the number of
stages needed for heating is determined, either Heat Stage 1 Relay

(Outputs→HEAT→HT.1), or Heat Stage 1 Relay
(Outputs→HEAT→HT.1) and Heat Stage 2 Relay
(Outputs→HEAT→HT.2) outputs will be turned on. See Gas

Heating Mode Using Space Temperature Sensor for more
information.

Supply--Air Temperature Sensor (SA

The SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) affects the Supply Air
Temperature (Temperatures→AIR.T→SAT) value displayed. This
configuration is accessible via the Scrolling Marquee on the SAT
Heat Mode Sensing (Configuration→HEAT→SAT→SAT.H).

When the SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) =DSBL, the Supply Air
Temperature (T emperatures→AIR.T→SAT) value on the
Scrolling Marquee and the CCN tables will be forced to zero when
heat outputs come ON and for 5 minutes after. The default Supply
Air Temperature (Temperatures→AIR.T→SAT) location is at the
fan inlet, upstream of the heat section.

When the SAT Heat Mode Sensing
(Configuration→HEAT→SAT→SAT.H) = ENBL, the Supply
Air Temperature (Temperatures→AIR.T→SAT) sensor reading is
displayed at the Scrolling Marquee and the CCN tables during
heating mode. This setting should only be used if the original SAT
sensor wires are removed from the Main Base Board (MBB) and
replaced by an accessory SAT sensor located in the supply duct
downstream of the heat section. There are then two supply air
temperature limits that become active, the Maximum SAT Lower
Level (Configuration→HEAT→SAT→SAM.L) the Maximum
SAT Upper Level (Configuration→HEAT→SAT→SAM.U).
Any time the supply air temperature rises above the Maximum
SAT Lower Level (Configuration→HEAT→SAT
heat staging will be limited to what is currently on and no
additional stages can be added until the supply air temperature falls
below the Maximum SAT Lower Level
(Configuration→HEAT→SAT→SAM.L). If the supply air
temperature rises above the Maximum SAT Upper Level
(Configuration→HEAT→SAT→SAM.U), then heating will be
reduced by removing a heat stage. That stage can not be added
again until the Supply Air Temperature
(Temperatures→AIR.T→SAT) falls below the Maximum SAT
Lower Level (Configuration→HEAT→SAT→SAM.L).Ifthe
supply air temperature stays above the Maximum SAT Upper
Level (Configuration→HEAT→SAT→SAM.U), then another
stage will be removed after the Heat Stage Decrease Time
(Configuration→HEAT→H.DEC).

Temperature Compensated Start

This logic is used when the unit is in the unoccupied state. The
control will calculate early Start Bias time based on Space
Temperature deviation from the occupied cooling and heating set
points. This will allow the control to start the unit so that the space
is at conditioned levels when the occupied period starts. This is
required for ASHRAE 90.1 compliance.

Setting Up the System

The settings for temperature compensated start can be found in the
local display under Configuration→UNIT.

ITEM EXPANSION RANGE UNITS CCN POINT

TCS.C

TCS.H

Temp Comp Strt Cool Factr (TCS.C)

This is the factor for the start time bias equation for cooling.

Temp Comp Strt Heat Factr (TCS.H)

This is the factor for the start time bias equation for heating.

IMPORTANT: Temperature compensated start is disabled when
these factors are set to 0.

Temp.Cmp.Strt.Cool Factr 0 --- 6 0 min TCSTCOOL

Temp.Cmp.Strt.Heat Factr 0 --- 6 0 min TCSTHEAT

T)

→SAM.L) the

22

Temperature Compensated Start Logic

The following conditions must be met for the algorithm to run:

S Unit is in unoccupied state.
S Next occupied time is valid.
S Current time of day is valid.
S Valid space temperature reading is available (sensor or CCN

network).

The algorithm will calculate a Start Bias time in minutes using the
following equations:

If (space temperature > occupied cooling set point)

Start Bias Time = (space temperature -- occupied cooling set
point)*TCS.C

If (space temperature < occupied heating set point)

Start Bias Time = (occupied heating set point -- space
temperature)*TCS.H

When the Start Bias Time is greater than zero the algorithm will
subtract it from the next occupied time to calculate the new start
time. When the new start time is reached, the Temperature
Compensated Start mode is set, the fan is started and the unit
controlled as in an occupied state. Once set, Temperature
Compensated mode will stay on until the unit goes into the
Occupied mode. The Start Bias Time will be written into the CCN
Linkage Equipment Table if the unit is controlled in DAV mode. If
the Unoccupied Economizer Free Cool mode is active when
temperature compensated start begins, the Unoccupied Free Cool
mode will be stopped.

IMPORTANT: The maximum minutes Start Bias can be is 180.

Carrier Comfort Network (CCN)R
Configuration

It is possible to configure the ComfortLink™ control to participate
as an element of the Carrier Comfort Network (CCN) system
directly from the local display. This section will deal with
explaining the various programmable options which are found
under the CCN sub-menu in the Configuration mode.

The major configurations for CCN programming are located in the
local displays at Configuration→CCN. See Appendix A.

CCN Address (CCN.A)

This configuration is the CCN address the rooftop is assigned.

CCN Address (CCN.B)

This configuration is the CCN bus the rooftop is assigned.

CCN Baud Rate (BAUD)

This configuration is the CCN baud rate.

CCN Time/Date Broadcast (BROD→B.TIM)

If this configuration is set to ON, the control will periodically send
the time and date out onto the CCN bus once a minute. If this
device is on a CCN network then it will be important to make sure
that only one device on the bus has this configuration set to ON. If
more than one time broadcaster is present, problems with the time
will occur.

IMPORTANT: Only the time and date broadcaster can perform

daylight savings time adjustments. Even if the rooftop is stand
alone, the user may want to set this to ON to accomplish the
daylight/savings function.

CCN OAT Broadcast (BROD→B.OAT)

If this configuration is set to ON, the control will periodically
broadcast its outside-air temperature at a rate of once every 30
minutes.

Global Schedule Broadcast (BROD→B.GS)

If this configuration is set to ON and the schedule number
(SCH.N) is between 65 and 99, then the control will broadcast the
internal time schedule once every 2 minutes.

CCN Broadcast Acknowledger (BROD→B.ACK)

If this configuration is set to ON, then when any broadcasting is
done on the bus, this device will respond to and acknowledge.
Only one device per bus can be configured for this option.

Schedule Number (SCH.O→SCH.N)

This configuration determines what schedule the control may
follow.

SCH.N = 0 The control is always occupied.

SCH.N = 1 The control follows its internal time

schedules. The user may enter any
number between 1 and 64 but it will
be overwritten to “1” by the control
as it only has one internal schedule.

SCH.N = 65--99 The control is either set up to

receive to a broadcasted time

schedule set to this number or the

control is set up to broadcast its

internal time schedule (B.GS)tothe

network and this is the global

schedule number it is broadcasting.

If this is the case, then the control

still follows its internal time

schedules.

Accept Global Holidays? (SCH.O→HOL.G)

If a device is broadcasting the time on the bus, it is possible to
accept the time yet not accept the global holiday from the broadcast
message.

Override Time Limit (SCH.O→OV.TL)

This configuration allows the user to decide how long an override
occurs when it is initiated. The override may be configured from 1
to 4 hours. If the time is set to 0, the override function will
become disabled.

Timed Override Hours (SCH.O→OV.EX)

This displays the current number of hours left in an override. It is
possible to cancel an override in progress by writing “0” to this
variable, thereby removing the override time left.

SPT Override Enabled? (SCH.O→OV.SP)

If a space sensor is present, then it is possible to override an
unoccupied period by pushing the override button on the T55 or
T56 sensor. This option allows the user to disable this function by
setting this configuration to NO.

Demand Limit

Demand Limit Control may override the cooling algorithm to limit
or reduce cooling capacity during run time. The term Demand
Limit Control refers to the restriction of machine capacity to
control the amount of power that a machine will use. This can save
the owner money by limiting peaks in the power supply. Demand
limit control is intended to interface with an external network
system. This is through a CCN Loadshed POC Device or writing
to network points.

To limit stages through network writes, the points Run Status
→COOL→MAX.C and Run Status→HEAT→MAX.H are forced
on the network through CCN points MAX_CAPC and
MAXHSTGS respectively. Force these to the desired maximum
cooling/dehumidification capacity and the maximum heating
stages, respectively. When there is no force on these points, they
automatically reset to allow full cooling/dehumidification capacity
and all heating stages to be used. These points are reset at
power-- on/reset (POR).

When using the Loadshed POC to do Demand Limiting, the cool
capacity and heat stage limits under both Redline and Loadshed
conditions can be set individually with configuration decisions. If
the active stages are greater then the loadshed or redline
configurations when a loadshed or redline command is given, the
unit will reduce capacity or remove stages. The configuration
points can be found in Configuration→CCN→LDS.

23

48/50PD

Loadshed Group Number (S.GRP)

This corresponds to the loadshed supervisory devices that reside
elsewhere on the CCN network and broadcast loadshed and redline
commands to its associated equipment parts. This variable will
default to zero which is an invalid group number. This allows the
loadshed function to be disabled until configured.

Redline Max Capacity (R.MXC)

This configuration tells the unit the maximum
cooling/dehumidification capacity allowed active during a
loadshed condition.

Redline Max Heat Stages (R.MXH)

This configuration tells the unit the maximum heating stages
allowed to be on during a redline condition.

Loadshed Max Heat Stages (R.MXH

This configuration tells the unit the maximum heating stages
allowed to be on during a loadshed condition.

The two Demand Limiting methods can be active simultaneously.
The lowest cool capacity and heat stage limits imposed by either
method are applied, and these “effective limits” are shown in the

48/50PD

points CAPLIMIT (Run Status→COOL→LMT.C)and
HSTGLIMT (Run Status→HEAT→LMT.H), respectively. In
normal running mode, these limits will prevent capacity/stages
from being added, or capacity/stages to be removed, as applicable.
In test mode, these limits are ignored, and the user may continue to
operate at full load.

The point MODEDMDL (Run Status→MODE→D.LMT)isused
to show if any Demand Limiting is in effect that prevents the unit
from operating either cooling or heating at full--capacity.

IMPORTANT: MODEDMDL may reflect that staging is NOT
limited even though Loadshed is active or the network points are
being forced, if the capacity/stage limits in effect are not less than
the capacity/stages present in the unit.

If a more drastic mode of Demand Limiting is required, the
network point HVACDOWN (Run Status→MODE→HV.DN) can
be used to prohibit the unit from selecting any HVAC mode, thus
preventing the operation of the supply fan, compressors, condenser
fans, and heat stages. This point must also be forced, and is reset
automatically when not forced, and at POR.

Alarm Handlin g

There are a variety of different alerts and alarms in the system.
Alerts are indicated by TXXX (where XXX is the alert number) on
the display and generally signify that the improperly functioning
circuit can restart without human interaction. If an alarm occurs,
indicated by AXXX (where XXX is the alarm numb er), the
damaged circuit will generally not restart without an alarm reset via
the Scrolling Marquee display or CCN.

The response of the control system to various alerts and alarms
depends on the seriousness of the particular alert or alarm. In the
mildest case, an alert does not affect the operation of the unit in any
manner. An alert can also cause a “strike.” A “striking” alert will
cause the circuit to shut down for 15 minutes. This feature reduces
the likelihood of false alarms causing a properly working system to
be shut down incorrectly. If three strikes occur before the circuit
has an opportunity to show that it can function properly, the circuit
will strike out, causing the shutdown alarm for that particular
circuit. Once activated, the shutdown alarm can only be cleared via
an alarm reset.

However, circuits with strikes will be given an opportunity to reset
their strike counter to zero. As discussed above, a strike typically
causes the circuit to shut down. Fifteen minutes later, that circuit
will once again be allowed to run. If the circuit is able to run for 1
minute, its replacement circuit will be allowed to shut down (if not
required to run to satisfy requested stages). However, the
“troubled” circuit must run continuously for a user defined time
(Configuration→COOL→RST.C) with no detectable problems

before the strike counter will be reset to zero. Default value is 5
minutes.

CCN Alarm Broadcast

Operators of CCN networks might not want to be notified of
“striking” alerts for refrigerant circuits until the circuit has been
shut down due to 3 strikes. Set the cooling configuration of Alert
Each Strike (Configuration→COOL→ALM.N on display,
ALM_NOW on CCN) to YES to broadcast each circuit strike alert.
Set Alert Each Strike to NO to broadcast only circuit shut down.
Alert Each Strike configuration is ignored during Service Test and
all alerts are broadcast.

Alarm Relay Output

The alarm relay output is a normally open 24 vac output between
field connection terminal board terminals C and X. Selection of
which alerts and alarms will result in closing of the alarm relay
may be set in the Alarm Relay Configuration
(Configuration→ALM.O). Setting a configuration to YES will
result in the alarm output relay, ALRM, status of ON and 24 vac
between C and X when that particular condition is in an alarm
state. Setting a configuration to NO will result in no action by the
alarm output relay for that particular condition.

IMPORTANT: An accessory filter switch can be used along with
the alarm relay output function to indicate dirty filter service need.

See the Troubleshooting section for more information on viewing,
diagnosing, and clearing alerts and alarms.

TROUBLESHOOTING

The Scrolling Marquee display shows the actual operating
conditions of the unit while it is running. If there are alarms or
there have been alarms, they will be displayed in either the current
alarm list or the history alarm list. (See Table 8.) The Service Test
mode allows proper operation of the compressors, fans, and other
components to be checked while the unit is not operating. See
Service Test.

Complete Unit Stoppage

There are several conditions that can cause the unit not to provide
heating or cooling:

S If an alarm is active which causes the unit to shut down,

diagnose the problem using the information provided in Alarms

and Alerts section below.

S Cooling and heating loads are satisfied.
S Programmed occupancy schedule.
S General power failure.
S Tripped CB1 or CB2 (24-volt transformer circuit breakers).
S Unit is turned off through the CCN network.
S If outdoor-air temperature is less than the Compressor Lockout

Temperature (CA.LO) configuration value, unit cannot cool.

S If outdoor-air temperature is greater than the Heating Lockout

Temperature (HT.LO) configuration value, unit cannot heat.

Restart Procedure

Before attempting to restart the machine, check the alarm list to
determine the cause of the shut down. If the shutdown alarm for a
particular control function has occurred, determine and correct the
cause before allowing the unit to run under its own control again.
When there is problem, the unit should be diagnosed in Service
Test mode. The alarms must be reset before the control function
can operate in either Normal mode or Service Test mode.

Control Module Communication

Red LED

Proper operation of the MBB, ECB and AUX1 control boards can
be visually checked by looking at the red status LEDs. When
operating correctly, the red status LEDs should blink in unison at a
rate of once every 2 seconds. If the red LED on the ECB and

24

AUX1 is not blinking, check the DIP switch positions on the
board. If the red LEDs are not blinking in unison, verify that
correct power is being supplied to all modules. A blinking red
LED at the rate of once per second means that software is not
loaded on the board. Also, be sure that the board is supplied with
the current software. If necessary, reload current software. A board
LED that is lit continuously should be replaced.

Green LED

The MBB, ECB and AUX1 each have one green LED. The Local
Equipment Network (LEN) LED should always be blinking
whenever power is on. If LEN LED is not blinking, check LEN
connections for potential communication errors (MBB J3, J4, and
J5). Communication between modules is accomplished by a 3-wire
sensor bus. These 3 wires run in parallel from module to module.
The J4 connector on the MBB also provides both power and
communication directly to the Scrolling Marquee display. The J5

Table 7 — LEN and CCN Communication Resistances

connector on the MBB provides a LEN interface at the field
connection terminal (TB).

Yellow LED

The MBB has one yellow LED which is used to indicate CCN
communication activity. The Carrier Comfort Network® (CCN)
LED will blink during times of network communication.

Communication Failures

If the Scrolling Marquee or Navigator display Communication
Failure or the green or yellow LED’s do not flash on the boards
then the problem could be the communication chip on one of the
control boards (MBB, ECB or AUX1). Use an ohm meter to
measure the resistance on the communication pins of the boards to
determine if the board is bad. If the reading is less than half the
value indicated in Table 7, then the board needs to be replaced.

Device

MBB

ECB

AUX1 ---

Board Serial

Number

Prior to 4702N

Starting 4702N

Prior to 0803N

Starting 0803N

(LEN) Resistance between Pins/

Pins 1 to 3 Pins 1 to 2 Pins 2 to 3 Pins 5 to 7 Pins 5 to 6 Pins 6 to 7

15K Ω

J3, J4, & J5

18.9K Ω

J3, J4, & J5

5.9K Ω
J2

18.9K Ω
J2

29K Ω

J9

Connector

7.5K Ω

J3, J4, & J5

9.9K Ω

J3, J4, & J5

5.2K Ω
J2

9.9K Ω
J2

16K Ω

J9

7.5K Ω

J3, J4, & J5

9.9K Ω

J3, J4, & J5

5K Ω

J2

9.9K Ω
J2

13.5K Ω
J9

(CCN) Resistance between Pins/

15K Ω

J5

18.9K Ω
J5

--- --- ---

--- --- ---

--- --- ---

IMPORTANT: The resistive values should be read when the board is powered off and the unit is locked out.

Alarms and Alerts

Viewing and Clearing Unit Alarms

Presence of active alarms will be indicated on the Scrolling
Marquee display by the Alarm Status light turning on and by the
number of active alarms being displayed in the automatic View of
Run Status. Presence of active alarms may also be signaled on the
Alarm Output terminals. Each alarm may also be broadcast on the
CCN network. Active alarms and past alarm history can be
reviewed and cleared via the local display or a CCN device. The
following menu locations are used for the local display:

Alarms→R.CURR (Reset All Current Alarms)

Change to YES to reset all active alarms. Turning unit power off
will also reset all current alarms.

Alarms→R.HIST (Reset Alarm History)

Change to YES to reset the alarm history. Turning unit power off
will not reset the alarm history.

Alarms→CURR (Currently Active Alarms)

Use the ENTER key, then scroll through any alarm numbers using
the up and down arrow keys. Alarms are displayed in numerical
order.

Alarms→HIST (Alarm History)

Use the ENTER key, then scroll through any alarm numbers using
the up and down arrow keys. Up to 20 alarms are displayed in
order of occurrence, with time and date.

The description for an alarm can be viewed on the Scrolling
Marquee display by pressing ESCAPE and ENTER keys
simultaneously while displaying the alarm code number. Be sure to
expand description for each code, because in some cases there are
different possible descriptions and causes for the same code
number.

Diagnostic Alarm Codes and Possible Causes

Alert Code T051

There are 5 different texts for this alert code. There are three
different alerts, two of which have corresponding test mode alerts
indicated with “Service Test” in the expanded text. Pressing enter
and esc on the marquee or navigator to expand the T051 alert will
show you one of the below alerts. Make sure the expanded text is
read correctly before troubleshooting.

S Digital Compressor Control Board Alarm

This alert occurs when the Digital Scroll Controller (DSC)

energizes its alarm relay. Refer to the DSC’s LED diagnostic to

determine which of the nine codes are present. Power cycle will

clear the DSC’s LED code. When the DSC’s alarm clears, this

alert will automatically clear.

S Compressor A1 Safety Trip

This Alert indicates that Current Sensing A1 (CS.A1) has been

enabled. The unit does not support the use of a current sensor at

this time. Change the CS.A1 to disable and this alert will clear

and not return.

(Configuration→COOL→CS.A1)

S Compressor A1 Current Detected After Turnoff

This Alert indicates that Current Sensing A1 (CS.A1) has been

enabled. The unit does not support the use of a current sensor at

this time. Change the CS.A1 to disable and this alert will clear

and not return.

(Configuration→COOL→CS.A1)

Alert Code T064 -- Circuit A Saturated Condensing
Temperature Thermistor Failure

This alert occurs when the temperature is outside the range -- 40_ to
240_F(--40_ to 116_C). When this occurs, the control will use

Connector

7.5K Ω
J5

9.9K Ω
J5

7.5K Ω
J5

9.9K Ω
J5

48/50PD

25

only the outdoor temperature to control the outdoor fans. If both
the SCT and OAT fail, then circuit shutdown alarm will occur also.
The cause of the alert is usually a faulty thermistor, a shorted or
open thermistor caused by a wiring error, or a loose connection.

Alert Code T066 -- Circuit A Saturated Suction Temperature
Thermistor Failure

This alert occurs when the unit’s suction transducers are turned off
internally. Cooling will not operate. This is usually due to a
network force on a non exposed CCN point. Reload factory
defaults or reinstall software o n the MBB. Consult the network
manager if alert continues.

Alert Code T073 -- Outdoor Air Temperature Thermistor
Failure

This alert occurs when the temperature is outside the range -- 40_ to
240_F(--40_ to 116_C). For all units, all ambient temperature
lockout limits for cooling and heating are ignored. For all units, if
both SCT and OAT fail, then circuit shutdown alarm will also
occur. For economizer equipped units, the economizer will not
operate to provide cooling. The economizer will still operate for
ventilation. The control will use condenser temperatures for
outdoor fan control. For units with CCH crankcase heat relay

48/50PD

control, the crankcase heat relay will be turned on if any
compressor is off. This alert resets automatically. The cause of the
alert is usually a faulty thermistor, a shorted or open thermistor
caused by a wiring error, or a loose connection.

Alert Code T074 -- Space Temperature Thermistor Failure

This alert occurs when the temperature is outside the range -- 40_ to
240_F(--40_ to 116_C). Cooling and heating will not operate. For
economizer equipped units, the economizer will still operate for
ventilation. This alert resets automatically. The cause of the alert is
usually a faulty thermistor in the T--55, T--56, or T--58 device, a
shorted or open thermistor caused by a wiring error, or a loose
connection.

Alert Code T075 -- Supply Air Temperature Thermistor
Failure

This alert occurs when the temperature is outside the range -- 40_ to
240_F(--40_ to 116_C). Economizer cooling and compressor
operation cannot occur while this alert is active. The unit will not
be allowed to enter cooling mode. This alert resets automatically.
The cause of the alert is usually a faulty thermistor, a shorted or
open thermistor caused by a wiring error, or a loose connection.

Alert Code T076 -- Return Air Thermistor Failure

This alert occurs when the temperature is outside the range -- 40_ to
240_F(--40_ to 116_C). Differential dry bulb crossover control
can not occur. Free cooling can only be controlled by the OAT and
enthalpy. This alert resets automatically. The cause of the alert is
usually a faulty thermistor, a shorted or open thermistor caused by
a wiring error, or a loose connection.

Alert Code T077 -- Space Relative Humidity Sensor Failure

This alert occurs when the input is less than 3.5 mA and the sensor
is configured as installed. If a humidistat is not installed, then
dehumidification will not be functional. Check sensor and wiring.
This alert clears automatically.

IMPORTANT: An ECB must be installed to use the space
relative humidity sensor.

Alert Code T092 -- Circuit A Suction Pressure Transducer
Failure

This alert occurs when the board does not properly read the
transducer voltage. A circuit cannot run when this alert is active.
Use the Scrolling Marquee to reset the alarm. The cause of the alert
is usually a faulty transducer, faulty 5 -- v power supply, or a loose
connection.

Alert Code T102 -- Compressor A1 Current Sensor Failure

This Alert indicates that Current Sensing A1 (CS.A1) has been
enabled. The unit does not support the use of a current sensor at

this time. Change the CS.A1 to disable and this alert will clear and
not return.
(Configuration→COOL→CS.A1)

Alert Code T110 -- Circuit A Lo ss of Charge

This alert has “Service Test” text that will be displayed if the alert
occurred during service test. This alert occurs when the
compressor is OFF and the suction pressure is less than 5 psig and
OAT is greater than -- 5_F for 1 continuous minute. Use the
Scrolling Marquee to reset the alert. The cause of the alert is
usually low refrigerant pressure or a faulty suction pressure. This
alert only occurs when the compressor is OFF because the low
refrigerant pressure alarms (alert T133) handle this situation when
the compressor is operating.

Alert Code T126 -- Circuit A High Discharge Pressure

This alert has “Service Test” text that will be displayed if the alert
occurred during service test. This alert occurs when alert T051 is
active while the appropriate condensing temperature is greater than
150_F. This alert reset automatically. The cause of the alert is
usually an overcharged system, high outdoor ambient temperature
coupled with dirty outdoor coil, plugged filter drier, or a faulty
high--pressure switch. See Alert T051 for diagnostic procedure.

Alert Code T133 -- Circuit A Low Refrigerant Pressure

This alert has “Service Test” text that will be displayed if the alert
occurred during service test. This alert occurs when the
compressor is operating and the evaporating temperature
(converted from the suction pressure) is less than configured low
suction control levels, Configuration→COOL→SST→SST.1
(Low Suction - Level 1) or SST.2 (Low Suction - Level 2) or
SST.3 (Low Suction Level 3). The circuit SST value must be less
than SST.1 (for 5 minutes), SST.2 (for 4 minutes), or SST.3 (for 3
minutes when using the economizer and 1.5 minutes when not
using the economizer) for the alert to occur. When the outdoor
temperature is less than 40_F, the above values are reduced 1_Ffor
every 2_F the OAT is below 40_F. An alert will also occur if the
circuit SST value is less than SST.3 --5_F for 20 seconds and the
outdoor temperature is above 40_F. All the above timers will reset
if the suction temperature rises above SST.O for 1 minute. This
alert causes a strike for the respective circuit. This alert will activate
when the coil becomes frosted. However, during the 15--minute
reset period, the coils will thaw and strike should clear and restart if
there is nothing else wrong with the circuit. The alert resets
automatically. The cause of the alert is usually low refrigerant
charge, dirty filters, evaporator fan operating backwards, loose or
broken belt, plugged filter drier, faulty transducer, excessively cold
return air, or stuck open economizer when the ambient temperature
is low.

Alert Code T143 -- Circuit A Failure to Pressurize

This alert has “Service Test” text that will be displayed if the alert
occurred during service test. This alert occurs when the
compressor turns on and the difference between suction and
discharge pressure is less then the Ckt A Minimum Pressure
(Configuration→COOL→SST→PSI.D). The pressure difference
must be greater then PSI.D (default is 20 psi) after 60 seconds and
stay above it while running the compressor. This alert causes a
strike for the respective circuit. The alert resets automatically. The
cause of the alert is usually compressor wiring causing reverse
rotation or a faulty compressor.

Alert Code T153 -- Real Time Clock Hardware Failure

This alert occurs when the RTC clock chip on the MBB is not
responding. Time and date functions will not operate, such as local
occupancy schedules. The unit will default to 24/7 unoccupied
mode. Recovery is automatic but MBB board replacement may be
necessary. Cycling power to the control and reconfiguring the time
and date should be tried before board replacement.

Alarm Code A154 -- Serial EEPROM Hardware Failure

The unit will completely shut down. The serial EEPROM chip on
the MBB, which stores the unit’s configuration, is not responding.

26

Recovery is automatic but MBB board replacement may be
necessary. Cycling the power to the control should be tried before
board replacement.

Alarm Code T155 -- Serial EEPROM Storage Failure Error

Configuration data in the serial EEPROM chip can not be verified.
The unit will run to last know good values or defaults, and
therefore operating errors may occur. Recovery is automatic but
MBB board replacement may be necessary. Cycling power to the
control and reconfiguring the control points should be tried before
board replacement.

Alarm Code A156 -- Critical Serial EEPROM Storage Fail
Error

The unit will completely shut down. Critical configuration data in
the serial EEPROM chip can not be verified. Recovery is automatic
but MBB board replacement may be necessary. Cycling power to
the control and reconfiguring the critical control points should be
tried before board replacement. There are no critical configurations
in the 48/50PD.

Alert Code A157 -- A/D Hardware Failure

The unit will completely shut down. The analog to digital
conversion chip on the MBB has failed. Recovery is automatic but
MBB board replacement may be necessary. Cycling power to the
control should be tried before board replacement.

Alert Code A163 -- Circuit A Down due to Failure

This alarm occurs when a circuit has 3 strikes. Use the Scrolling
Marquee display to reset the alarm. Investigate the alarm that
caused the strikes to occur.

Alert Code T178 -- Loss of Communication with the Capacity
Control Board

This alert occurs when the MBB cannot communicate with the
AUX1 board. Unit operation will b e disabled. This is usually
caused by a wiring problem. Investigate using the Low Voltage
Schematic, check that the AUX1 address is correct, and verify the
resistance between pins on the LEN connections.

Alert Code T179 -- Loss of Communication with the
Economizer Control Board

This alert occurs when the MBB cannot communicate with the
ECB. Economizer operation will be disabled. This is usually
caused by a wiring problem. If a relative humidity sensor is
installed and configured but there is not an ECB installed on the
unit, this alert will be generated (the ECB is required for RH sensor
operation). Investigate using the Low Voltage Schematic, check
that the ECB address is correct, and verify the resistance between
pins on the LEN connections.

Alert Code T180 -- Loss of Communication with the
Economizer Actuator

This alert occurs when the ECB cannot communicate with the
Belimo Actuator. If the analog signal is connected properly, the
economizer will still be controlled through it. This is usually
caused by a wiring problem, actuator failure, or the wrong actuator.
Investigate using the Low Voltage Schematic, make sure the
actuator is a MFT communication actuator, and verify the feedback
signal from the actuator is correct.

Alarm Code A200 -- Linkage Timeout -- Comm Failure

This alarm occurs when the MBB fails to communicate with a
Linkage device. This only occurs when the MBB has previously
communicated with a Linkage device since last power cycle. If a
back up sensor was not installed the T074 alert will occur shortly
after this one. Reset power to the unit and verify Linkage is
communicating.

Alarm Code A404 -- Fire Shutdown

This alarm occurs when the shutdown input is either open or
closed depending upon its configuration. This alarm is usually
caused by an auxiliary device that is trying to shut down the unit,
e.g., smoke detector. The configuration for this switch input can be

found at variable Configuration→UNIT→FS.SW. Verify that the
configuration is set correct, verify the wiring and auxiliary device.
This alarm resets automatically.

Alert Code T408 -- Dirty Air Filter

This alert occurs when the Filter Status switch senses a plugged
filter for 120 continuous seconds after the indoor fan has been
running for 10 seconds. Because the Dirty Air Filter switch can be
configured normally opened or closed, the switch might be open or
closed. The configuration for this switch input can be found at
variable Configuration→UNIT→FL.SW. Verify that the
configuration is set correct and verify the wiring and filter status
switch. The hose should be connected to the low side of the switch.
This alert resets automatically.

Alert Code T409

There are 2 different texts for this alert code. Pressing enter and esc
on the marquee or navigator to expand the T409 alert will show
you one of the below alerts. Make sure the expanded text is read
correctly before troubleshooting.

S Fan Status Switch On, Fan Contactor Off

This alarm occurs when the fan status switch has sensed that the

indoor fan has been on for 10 seconds and the indoor fan

feedback has determined that the indoor fan should be off.

Because the Fan Status switch can be configured normally

opened or closed, the switch might be open or closed. The

configuration for this switch input can be found at

Configuration→UNIT→FN.SW. Verify that the configuration

is set correctly. Verify the wiring and fan status switch. The hose

should be connected to the high side of the switch. If the IDF is

configured to shut down the unit when this alarm occurs

(Configuration→UNIT→IDF.F = YES), then this alarm can

only be reset manually and the unit is shut down. If the IDF is

not configured to shut the unit down when this alarm occurs

(IDF.F = NO), then this alarm resets automatically and no

specific control action is taken.

S Fan Status Switch Off, Fan Contactor On

This alert occurs when the fan status switch has sensed that the

indoor fan has been off for 10 seconds and the indoor fan

feedback has determined that the indoor fan should be on.

Because the Fan Status switch can be configured normally

opened or closed, the switch might be open or closed. The

configuration for this switch input can be found at

Configuration→UNIT→FN.SW. Verify that the configuration

is set correctly. Verify the wiring and fan status switch. The hose

should be connected to the high side of the switch. If the IDF is

configured to shut down the unit down when this alert occurs

(Configuration→UNIT→IDF.F = YES), then this alarm can

only be reset manually and the unit is shut down. If the IDF is

not configured to shut the unit down when this alert occurs

(IDF.F = NO), then this alert resets automatically and no specific

control action is taken.

Alert Code T414

There are 6 different alerts under this one alert code. Pressing enter
and esc on the marquee or navigator to expand the T414 alert will
show you one of the below alerts. All these alerts are generated by
the Belimo actuator and reported to the ECB. These alerts can only
occur if the ECB is controlling the actuator digitally through MFT.

S Economizer Damper Actuator Out of Calibration

This alert occurs when the economizer actuator reports a control

angle (Operating Modes→ECON→C.ANG) less than the

minimum control angle (Configuration→ECON→M.ANG).

27

48/50PD

Initiate economizer calibration (Service Test→INDP→ E.CAL)

using the Service Test menu. The economizer calibration

procedure will try to find new maximum open and closed

positions. If the alert does not clear automatically after the

calibration procedure is complete, investigate what is limiting

economizer rotation. After that step, run another calibration, but

first power off unit (spring return the damper), loosen the

actuator clamp, and while pushing the damper closed tighten the

clamp. This alert resets automatically.

S Economizer Damper Actuator Torque Above Load Limit

This alert occurs when the actuator load is too high. Investigate

to determine what is increasing damper load and verify that the

actuator is the correct size for the unit. This alert resets

automatically.

S Economizer Damper Actuator Hunting

This alert occurs when the commanded damper position is

changing too rapidly. The stop jog ration must be less than 21%

to clear this alert. Leave the actuator powered with no signal for

a few hours to allow the ratio to decrease (may have to wait

longer than a few hours). If the alert continues, determine if the

ECB or actuator is bad. This alert resets automatically.

S Economizer Damper Stuck or Jammed

This alarm occurs when the actuator senses it can no longer

move. Investigate what is stopping the rotation of the actuator

and fix. This alert resets automatically.

S Economizer Damper Actuator Mechanical Failure

This alert occurs when the actuator senses a catastrophic failure.

Investigate actuator and replace if necessary. This alert resets

Excessively

automatically.

S Economizer Damper Actuator Direction Switch Wrong Position

This alert occurs when the economizer damper direction switch

48/50PD

is in the wrong position. The direction switch should be in the

clockwise position and the actuator should be mounted so that

the CW face of the actuator is accessible. Correct if necessary.

This alert clears automatically.

Alert Code T415 -- IAQ Input Out of Range

This alert occurs when the IAQ input (on ECB) is less than 3.5 mA
and the sensor is configured as installed. IAQ operation will be
disabled. Check sensor and wiring. This alert clears automatically.

Alert Code T416 -- OAQ Input Out of Range

This alert occurs when the OAQ input (on ECB) is less than 3.5
mA and the sensor is configured as installed. OAQ operation will
be disabled. Check sensor and wiring. This alert clears
automatically.

28

Table 8 — ComfortLink™ Alarm Codes

ALARM

OR

ALERT

NUMBER

T051

T064

T066

T073 Outdoor Air Temperature Thermistor Failure

T074 Space Temperature Thermistor Failure No heating or cooling Automatic

T075 Supply Air Temperature Thermistor Failure No cooling mode Automatic

T076 Return Air Thermistor Failure

T077 Space Relative Humidity Sen sor Failur e

T092

T102 Compressor A1 Current Sensor Failure

T110

T126

T133

T143

T153 Real Timeclock Hardware Failure

A154 Serial EEPROM Hardware Failure Unit Shutdown Automatic Software failure or MBB failure

T155 Serial EEPROM Storage Failure Error Unit operation errors Automatic Software failure or MBB failure
A156 Critical Serial EEPROM Storage Fail Error Unit Shutdown Automatic Software failure or MBB failure
A157 A/D Hardware Failure Unit Shutdown Automatic Software failure or MBB failure

A163

* See Legend on next page

Digital Compressor Control Board Alarm No action Automatic See the DSC’s LEDs for troubleshooting

Compressor A1 Safety Trip Add Strike for Circu it A Automatic

Service Test --- Compressor A1 Safety Trip Add Strike for Circuit A Automatic

Compressor A1 Current Detected After
Turnof f
Service Test --- Compressor A1 Current
Detected After Turnoff
Circuit A Saturated Condensing Temp
Thermistor Failure
Circuit A Saturated Suction Temperature
Thermistor Failure

Circuit A Suction Pressure Transducer
Failure

Circuit A Loss of Charge Shutdown Circuit A Manual Low refrigerant or faulty suction pressure transducer
Service Test --- Circuit A Loss of Charge Shutdown Circuit A Manual Low refrigerant or faulty suction pressure transducer

Circuit A High Discharge Pressure Shutdown Circuit A Automatic

Service Test --- Circuit A High Discharge
Pressure

Circuit A Low Refrigerant Pressure Add Strike for Circuit A Automatic

Service Test --- Circuit A Low Refrigerant
Pressure

Circuit A Failure To Pressurize Add Strike for Circuit A Automatic Wiring causing reverse rotation or faulty compressor
Service Test --- Circuit A Failure To
Pressurize

Circuit A Down Due to Failure Shutdown Circuit A Manual

Service Test --- Circuit A Down Due to
Failure

DESCRIPTION

ACTION TAKEN BY

CONTROL

Turn o f f all

compressors

Turn o f f all

compressors

Use OAT to control

Outdoor fans

No Cooling Automatic Suction transducers internally forced inactive

No cooling with

economizer

No differential DB

crossover

If RH.S = Yes, then no

indoor hu midity control

Shutdown Circuit A Manual

If C S.A1 = Enable,

then no T051 current

alarm

Shutdown Circuit A Automatic

Add Strike for Circuit A Automatic

Add Strike for Circuit A Automatic Wiring causing reverse rotation or faulty compressor

No time and date

schedul e operation

Shutdown Circuit A Manual

RESET

METHOD

Automatic

Automatic

Automatic

Automatic

Automatic

Automatic

Automatic

Automatic

PROBABLE CAUSE

Current Sensing turned on (CS.A1 = Enable) and
should be off
Current Sensing turned on (CS.A1 = Enable) and
should be off
Current Sensing turned on (CS.A1 = Enable) and
should be off
Current Sensing turned on (CS.A1 = Enable) and
should be off
Faulty, shorted, or open thermistor caused by wiring
error or loose connection.

Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
Faulty, shorted, or open sensor caused by wiring
error or loose connection.
Faulty transducer, faulty 5 ---V power supply, or loose
connection

Current Sensing turned on (CS.A1 = Enable) and
should be off

An overcharged system, high outdoor ambient
temperature coupled with dirty outdoor coil, plugged
filter drier, or a faulty high --- pressure switch.
An overcharged system, high outdoor ambient
temperature coupled with dirty outdoor coil, plugged
filter drier, or a faulty high --- pressure switch.
Low refrigerant charge, dirty filters, evaporator fan
turning backwards, loose or broken fan belt, plugged
filter drier, faulty transducer, excessively cold return
air, or stuck open economizer when the ambient
temperature is low.
Low refrigerant charge, dirty filters, evaporator fan
turning backwards, loose or broken fan belt, plugged
filter drier, faulty transducer, excessively cold return
air, or stuck open economizer when the ambient
temperature is low.

No time/date configured, software failure, or MBB
failure

Circuit has 3 strikes or has been locked out by
another alarm
Circuit has 1 strike or has been locked out by another
alarm

48/50PD

29

Table 8 — ComfortLink™ Alarm Codes (cont)

ALARM

OR

ALERT

NUMBER

T178

T179

T180

A200 Linkage Timeout Error --- Comm Failure

A404 Fire Shutdown Unit Shutdown Automatic Smoke detected by smoke detector

T408 Dirty Filter Alert Generated Automatic Dirty Filter

T409

48/50PD

T414

T415 IAQ Input Out of Range No IAQ Operations Automatic

T416 OAQ Input Out of Range No OAQ Operations Automatic

LEGEND

ECB -- Economizer Control Board
IGC -- Integrated Gas Controller
MBB -- Main Base Board
OAT -- Outdoor--Air Thermistor

Loss of Communication with the Capacity
Control Board
Loss of communication with the Economizer
Control Board
Loss of communication with the Economizer
Actuator

Fan Status Switch ON, Fan Contactor OFF

Fan Status Switch OFF, Fan Contactor ON

Economizer Damper Actuator Out of
Calibration
Economizer Damper Actuator Torque Above
Load Limit
Economizer Damper Actuator Hunting
Excessively

Economizer Damper Stuck or Jammed Alert Generated Automatic

Economizer Damper Actuator Mechanical
Failure
Economizer Damper Actuator Direction
Switch Wrong

DESCRIPTION

ACTION TAKEN BY

CONTROL

Unit shutdown ---HVAC

disable

No economizer

operation

No economizer

operation

No Linkage Operation

fall back to local SPT

If IDF.F = Yes, then Unit

Shutdown

If IDF.F = Yes, then Unit

Shutdown

Alert Generated Automatic

Alert Generated Automatic Actuator load too high. Check damper load.

Alert Generated Automatic Damper position changing too quickly.

Alert Generated Automatic Check actuator and replace if necessary.

Alert Generated Automatic Actuator direction control switch (CCW, CW) wrong.

RESET

METHOD

Automatic

Automatic

Automatic Communication wiring problem with actuator.

Automatic

If IDF.F =

YES, then

Manual,
otherwise
automatic

If IDF.F =

YES, then

Manual,
otherwise
automatic

Communication wiring problem with AUX1 or faulty
MBB, ECB, or AUX1
Communication wiring problem with ECB or faulty
MBB, ECB, or AUX1

Received a table write from Linkage before, now not
receiving any linked commands

Bad Fan Status Switch. Configuration incorrect.

Tripped Circuit Breaker. Broken belt. Bad indoor fan
motor. Configuration incorrect. Bad fan status switch.

Calibrate economizer (E.CAL). If problem still exist
then determine what is limiting economizer rotation.

No economizer motion. Check damper blades, gears,
and actuator.

Bad sensor, bad wiring, or sensor configured
incorrectly.
Bad sensor, bad wiring, or sensor configured
incorrectly.

PROBABLE CAUSE

Cooling Troubleshooting

Use the Scrolling Marquee display or a CCN device to view the
cooling status display and the cooling diagnostic display (see
Appendix A) for information on the cooling operation. Check the
current alarms and alarm history for any cooling alarm codes and
correct any causes. (See Table 9.)

Verify any unique control configurations per installed site
requirements or accessories. If alarms conditions are corrected and
cleared, operation of the compressors and fans may be verified by
using the Service Test mode. (See Table 5.) See Table 9 for general
cooling service analysis.

30

Table 9 — Cooling Service Analysis

Compressor and Fan Will Not Start Power failure. Call power company.

CompressorCycles(otherthan
normally satisfying demand).

Compressor Operates
Continuously.

Excessive Condenser Pressures. Loose condenser thermistors. Tighten thermistors.

Condenser Fans Not Operating. No Power to contactors. Fuse blown or plug at motor loose.
Excessive Suction Pressure. High heat load. Check for sources and eliminate

Suction Pressure Too Low. Dirty air filters. Replace air filters.

PROBLEM CAUSE REMEDY

LEGEND

CB -- Circuit Breaker
DSC -- Digital Scroll Controller
TXV -- Thermostatic Expansion Valve
VFD -- Variable Frequency Drive

Fuse blown or circuit breaker tripped. Check CB1 and
CB2.

Disconnect off. Power disconnect.
Compressor time guard to prevent short cycling. Check time guards using ComfortLinkt Scrolling

Occupancy schedule set point or supply set point not
calling for Cooling.

Outdoor temperature too low. Check Compressor Lockout Temperature using

Active alarm. Check active alarms using ComfortLink Scrolling

Insufficient line voltage. Determine cause and correct.
Active alarm. Check active alarms using ComfortLink Scrolling

Unit undersized for load. Decrease load or increase size of unit.
Occupancy schedule set point or supply set point too

low. Compressor running at lowest capacity
Compressor contactor stuck on Check cooling demand using ComfortLink Scrolling

Dirty air filters. Replace filters.
Low refrigerant charge. Check pressure, locate leak, repair, evacuate, and

Condenser coil dirty or restricted. Clean coil or remove restriction.

Dirty condenser coil. Clean coil.
Refrigerant overcharge. Recover excess refrigerant.
Faulty TXV.

Condenser air restricted or air short cycling. Determine cause and correct.
Restrictioninliquidtube. Remove restriction.

Faulty TXV.

Refrigerant overcharged. Recover excess refrigerant.

Low refrigerant charge. Check pressure, locate leak, repair, evacuate, and

Faulty TXV.

Insufficient evaporator airflow. Check belt tension. Check for other restrictions.
Indoor Fan Running to slow or off while compressor isonCheck VFD display is illuminated and shows Auto

Temperature too low in conditioned area (low
return --- air temperature).

Replace fuse or reset circuit breaker.

Marquee also the DSC has a 2 minute anti--- short time
Check cooling demand using ComfortLink Scrolling

Marquee.

ComfortLink Scrolling Marquee.

Marquee and DSC alert flash codes

Marquee and DSC alert flash codes

Check and adjust set points if needed.

Marquee and DSC alert flash codes.

recharge.

1.Check TXV bulb mounting and secure tightly to suction
line and insulate.

2.Replace TXV (and filter drier) if stuck open or closed.

1.Check TXV bulb mounting and secure tightly to suction
line and insulate.

2.Replace TXV (and filter drier) if stuck open or closed.

recharge.

1.Check TXV bulb mounting and secure tightly to suction
line and insulate.

2.Replace TXV (and filter drier) if stuck open or closed.

mode. Power supplied to VFD. Check 0 --- 10vdc signal
present at AUX1 board.

Reset thermostat or occupancy schedule.

48/50PD

Digital S croll Controller (DSC) Troubleshooting

The 48/50PD units are equipped with a digital scroll compressor.
The compressor has a solenoid unloader that is controlled by the
digital scroll controller (DSC). This DSC turns the unloader on
and off within a 20 second window. The amount of time the
unloader is on verses off within that 20 seconds depends on the
desired capacity. This means that the ComfortLink control does
not have direct control of the compressor, but it does however
control the power to the DSC and the signal for commanded
capacity.

The DSC has three LED lights to help during troubleshooting;
green, yellow, and red The DSC will run the compressor
unloaded for a half a second on start up and one second on
shutdown to prevent reverse rotation. A two minute anti-- short
time guard is applied by the DSC after shutting the compressor off.
The DSC has an alarm relay output that is connected to the MBB.
When this MBB input switch is closed, the MBB activates the
T051 alert. Check the LED status on the DSC for flash alarm

codes and correct any problems. Table 10 shows the DSC’s Red
LED flash codes.

POWER LED (green) ⎯ indicates voltage is present at the
24VAC power terminal. When the 2 minute anti--short cycle timer
is active, the green LED will flash.

UNLOADED LED (yellow) ⎯ indicates the unloader solenoid
status. The LED is on when the unloader solenoid is energized.

ALERT LED (red) ⎯ communicates an abnormal system
condition through a unique flash code.

All LEDs Flashing at the Same Rate ⎯ indicates 24VAC supply
is too low for operation.

All LEDs On Solid at the Same Time ⎯ indicates Digital Scroll
Controller failure.

Flash Code 1 ⎯ Reserved for future use
Flash Code 2 ⎯ High Discharge Temperature

This occurs when the discharge temperature thermistor (DTT) has

31

measured a temperature above 268 F (131 C) or the thermistor has
short circuited (jumpered out).

The DSC will de--energize the compressor contactor and unloader
solenoid, and the alarm relay contacts will close causing a T051
alert on the ComfortLink Control. The compressor will be
allowed to restart after 30 minute delay and after the DTT reads
below 250 F (120 C). The flash code and alarm relay contacts will
be reset after the compressor has run for 60 minutes without any
other ALERTs. If five discharge temperature ALERTs have
occurred within four hours, the DSC will lock out the compressor.
The lockout can only be reset by cycling the 24VAC power off and
on.

Flash Code 3 ⎯ Compressor Protector Trip
This occurs when the demand signal from the system controller is
greater than 1.44VDC and there is no compressor current detected.
This could be due to the compressor’s internal overload protector
being open, fuse or breaker open, power disconnected to
compressor contactor, compressor power wiring not run through
DSC current transformer port or a compressor contactor failure.
The DSC will de--energize the compressor contactor and unloader
solenoid and the alarm relay contacts will close causing a T051

48/50PD

alert on the ComfortLink Control. The DSC will wait for the two
minute anti--short cycle timer to time out and if the system
controller demand signal is still greater than 1.44VDC, energize the
compressor contactor again. If compressor current is detected on
the restart, the ALERT code and alarm relay output will reset. The
DSC will attempt to restart compressor as long as the system
controller demand is above 1.44VDC. There is no lockout feature
for this ALERT.

Flash Code 4 ⎯ Locked Rotor
A locked rotor condition in the compressor is sensed by the DSC
on four consecutive start ups. The DSC will de--energize the
compressor contactor and unloader solenoid and the alarm relay
contacts will close causing a T051 alert on the ComfortLink
Control. This code results in a lockout and can only be reset by
cycling the 24VAC power off and on.

Flash Code 5 ⎯ Demand Signal Loss
This occurs when the demand signal input has dropped below

0.5VDC. The demand input signal wire may be disconnected or

the system controller providing the signal may not be powered.
The DSC will de--energize the compressor contactor and unloader
solenoid and the alarm relay contacts will close causing a T051
alert on the ComfortLink Control. Once the system controller
demand signal input has risen above 0.5VDC, the ALERT code
and alarm relay output will reset. If the demand signal is above

1.44VDC and the anti--short cycle timer has timed out, the
compressor will restart.

Flash Code 6 ⎯ Discharge Thermistor Fault
This occurs when the DSC is not receiving a signal from the
discharge temperature thermistor (DTT). The thermistor may be
missing, disconnected or a wire broken. The alarm relay contacts
will close and the DSC will not increase the capacity of the
compressor beyond 50% loading. This ALERT code and alarm
relay output are reset by reconnecting the DTT.

Flash Code 7 ⎯Reserved for future use

Flash Code 8 ⎯ Compressor Contactor Fault

This occurs when the compressor current is detected when the
system controller demand signal is below 1.44VDC. The
compressor contactor may have welded contacts or the contacts
may be mechanically jammed. The compressor will continue to run
in this condition since the DSC cannot open the compressor
contactor. The DSC will energize the compressor contactor and the
alarm relay contacts will close causing a T051 alert on the
ComfortLink Control. The unloader solenoid will remain
energized causing the compressor to run unloaded as long as the
system controller demand signal is less than 1.44VDC. If the
system controller demand is greater than 1.44VDC, the unloader
solenoid will de--energize causing the compressor to run loaded.
The ALERT code and alarm relay output are reset when current is
no longer detected while system controller demand signal is below

1.44VDC.
Flash Code 9 ⎯ Low 24VAC Supply

This occurs when the supply voltage to the DSC has dropped
below 18.5VDC. The DSC will de-- energize the compressor
contactor and unloader solenoid. The alarm relay contacts may
close if the voltage is high enough for the alarm relay to pull in.
The ALERT code and alarm relay output are reset when the supply
voltage to the DSC rises above 19.5VAC.

LED Flash

Code

1

Flash

2

Flash

3

Flash

4

Flash

5

Flash

6

Flash

7

Flash

8

Flash

9

Flash

Table 10 — DSC Red LED Flash Codes

Description Action Taken

by Control

Reserved for Future Use N/A N/A N/A

High Discharge Temperature Compressor

shutdown

Compressor Protector Trip Compressor

shutdown

Locked Rotor Compressor

lockout

Demand Signal Loss Compressor

shutdown

Discharge Thermistor Fault Capacity Limited Automatic DTT may be missing, disconnected or a wire broken

Reserved for Future Use N/A N/A N/A

Compressor Contactor Fault Keep capacity

at 15%

Low 24VAC Supply Compressor

shutdown

Reset

Method

Automatic Compressor discharge temperature is greater then 268

degrees F or the DTT is shorted.

Automatic Compressor’s internal overload protector being open,

fuse or breaker open, power disconnected to compres­sor contactor, compressor power wiring not run through
DSC current transformer port or a compressor contactor
failure.

Manual Four consecutive start ups with locked rotor.

Automatic Signal wire may be disconnected or the system control-

ler providing the signal may not be powered

Automatic Compressor contactor may have welded contacts or the

contacts may be mechanically jammed

Automatic Bad connection or transformer.

Probable Cause

32

Economizer Troubleshooting

Use the unit Scrolling Marquee display or a CCN device to view
the economizer status display and the economizer diagnostic
display (see Appendix A) for information on the economizer
operation. Check the current alarms and alarm history for any
economizer alarm codes and correct any causes. (See Table 11.)

Verify any unique control configurations per installed site
requirements or accessories. If alarms conditions are corrected and
cleared, operation of the economizer may be verified by using the
Service Test mode (see Service Test section and T able 5). The
following steps specify how to test the economizer using the
Scrolling Marquee display. See Table 11 for general economizer
service analysis.

1. Enter the Service Test main menu on the display.

2. Enter TEST and turn ON test mode. A password may be
needed in order to turn ON the Service Test. The default
password is 1111.

3. Return to the main level of Service Test.

4. Enter the INDP submenu and enter an initial value for
ECON. This will drive the economizer damper to the
specified position. Continue to adjust the ECON value to
make sure the economizer opens and closes.

5. Because of a mechanical problem with the economizer, the
actuator might acquire a new degree of rotation which is
less than M.ANG. If this occurs, a “T414 Economizer
Damper Actuator Out of Calibration” alert will be
generated. This alert can only occur if the economizer is
using digital communications (Configuration
→ECON→E.CTL = 1or2). The economizer calibration
procedure (Service Test→IND.P→E.CAL) will reconfigure
the actuator to the new fully closed and fully open
positions. To implement the calibration procedure, change
E.CAL from OFF to ON. E.CAL will remain ON as long as
the calibration procedure is being implemented (as long as 5
minutes). During the calibration procedure the actuator will
close fully and then open fully. After the calibration is
complete, the degree of rotation should be greater than
M.ANG, causing the T414 alert to clear. If the T414 alert
does not clear, check the economizer damper for other
mechanical problems.

6. Return to Service Test→TEST and turn OFF test mode.
This will cause the unit to return to normal operation.

Table 11 — Economizer Service Analysis

Damper Does Not Move. Indoor Fan is off. Check for proper VFD connections. Check that

Economizer Operation is Limited
to Minimum Position.

Economizer Position is Less
Than Minimum Position.

Economizer Does Not Return
to Minimum Position.

Damper Does Not Close on Power
Loss.

Outdoor Damper Does Not Fully Close
at 0% or Fully Open at 100%.

Economizer is not a configured
minimum position

LEGEND

CCN -- Carrier Comfort Network
IAQ -- Indoor Air Quality
VFD -- Variable Frequency Drive

PROBLEM POSSIBLE CAUSE REMEDY

VFD is illuminated and in Auto mode.
Unit is not configured for continuous fan operation

and there are no cooling or heating demands.
Unit is in Unoccupied mode and there is no call for

heating or cooling.
Tripped circuit breaker.
No power to the unit.

Actuator is unplugged at motor or at economizer board. Check wiring connections.
Unit is not configured for economizer. Configure unit for economizer per the

Outdoor--- air temperature is above economizer
high temperature lockout.

Outdoor---air temperature is below economizer low
temperature lockout.

Communication loss to economizer board. Check wiring connections.
Damper is jammed. Identify the obstruction and safely remove.
Minimum position is set incorrectly. Adjust minimum position setting.
Outdoor--- air temperature is above economizer

high temperature lockout.

Outdoor---air temperature is below economizer
low temperature lockout.

Outdoor---air thermistor is faulty. Replace outdoor--- air thermistor.
Low suction pressure problem with a compressor. Economizer is operating correctly, identify

IAQ is controlling minimum damper position. Adjust the IAQ settings if incorrect,

Unit is in Unoccupied mode. Adjust unit occupied schedule if incorrect,

Damper is jammed. Identify the obstruction and safely remove.
Unit is operating under free cooling. Economizer is operating correctly.

Damper is jammed or spring return is backwards. Identify the obstruction and safely remove.

Economizer actuator is out of calibration. Enter Service Test mode and run the Calibrate

Unit is operating under free cooling. Economizer is operating correctly.
Unit fan speed is offsetting the economizer minimum

position to maintain proper ventilation.

Unit is off via CCN command.

instructions.
Adjust the high temperature lockout setting if it is

incorrect, otherwise, economizer is operating
correctly.

Adjust the low temperature lockout setting if it is
incorrect, otherwise, economizer is operating
correctly.

Adjust the high temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly.

Adjust the low temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly.

compressor problem.

otherwise, the economizer is operating correctly.

otherwise, economizer is operating correctly.

Remove actuator, flip it over and re---install.

Economizer (E.CAL) procedure.

Economizer is operating correctly.

48/50PD

33

Heating Troubleshooting

Use the unit Scrolling Marquee display or a CCN device to view
the heating status display and the heating diagnostic display (see
Appendix A) for information on the heating operation. Check the
current alarms and alarm history for any heating alarm codes and
correct any causes. (See Table 12.) Verify any unique control
configurations per installed site requirements or accessories. If
alarms conditions are corrected and cleared, operation of the heat
stages and indoor fan may be verified by using the Service Test
mode. (See Table 5.)

Gas Heat (48PD Units Only)

See Table 12 for general gas heating service analysis. See Fig. 9 for
service analysis of the IGC board logic. Check the status LED on
the IGC board for any flashing alarm codes and correct any causes.
(See Table 13.)

Electric Heat (50PD Units Only)

See Table 14 for electric heating service analysis.

Variable Frequency Drive (VFD) Troubleshooting

The VFD must be in “Auto” mode and when commanding it to

48/50PD

100% the voltage signal should be 10vdc across AI1 and AIGND.
Verify all parameters are correct to factory defaults. See Appendix
B for parameters and additional troubleshooting.

Phase Loss Protection

The phase loss protection option will monitor the three-phase
electrical system to provide phase reversal and phase loss

Phase Reversal Protection

If the control senses an incorrect phase relationship, the relay (K1)
will be de-energized (opening its contact). If the phase relationship
is correct, the relay will be energized. The control has a self-bypass
function after a pre-set time. If the control determines that the three
phases stay in a correct relationship for 10 consecutive minutes, the
relay will stay energized regardless of the phase sequence of three
inputs as long as 24-vac control voltage is applied. This self-bypass
function will be reset if all three phases are restored in a phase loss
event.

Phase Loss Protection

If the reverse rotation board senses any one of the three phase
inputs has no AC voltage, the relay will be de--energized (opening
its contact). This protection is always active as long as 24-vac
control voltage is applied, and is not affected by the self by-pass
function of the phase sequence monitoring function. However, in
the event of phase loss, the relay will be re-energized only if all
three phases are restored and the three phases are in the correct
sequence.

A red LED is provided to indicate the function of the board. See
the table below.

LED STATUS FUNCTION

On Continuously Relay contact closed (normal operation).

Blinking

Off 24 vac control power not present (off).

Relay contact open (phase loss or phase
reversal has occurred) --- No power will be
supplied to the control system.

protection.

Table 12 — Gas Heating Service Analysis

Burners Will Not Ignite. Unit is not configured for heat. Check heating configurations using ComfortLinkt Scrolling

Inadequate Heating. Dirty air filters. Replace air filters.

Poor Flame
Characteristics.

Burners Will Not Turn Off. Unit is in Minimum on---time. Check using ComfortLinkt Scrolling Marquee and the IGC alert

PROBLEM CAUSE REMEDY

Active alarm. Check active alarms using ComfortLinkt Scrolling Marquee and

No power to unit. Check power supply, fuses, wiring, and circuit breakers.
No power to IGC. Check fuses and plugs.
Heaters off due to time guard to prevent short

cycling.
Occupancy schedule set point not calling for

Heating.
No gas at main burners. Check gas line for air and purge as necessary. After purging gas

Water in gas line . Drain water and install drip.

Gas input too low. Check gas pressure at manifold. Refer to gas valve adjustment in

Occupancy schedule set point set too low. Check setpoints and adjust if necessary.
Unit undersized for load. Decrease load or increase of size of unit.
Restricted or low airflow. Remove restriction, verify proper fan speed operation, and check

Too much outdoor air. Check economizer position and configuration. Adjust minimum

Limitswitchcyclesmainburners. Check rotation of blower and temperature rise of unit. Adjust as

Incomplete combustion (lack of combustion air)
results in: Aldehyde odors, CO, sooting flame, or
floating flame.

Unit running in Service Test mode. Check using ComfortLinkt Scrolling Marquee.
Main gas valve stuck. Turn off gas supply and unit power. Replace gas valve.

LEGEND

IGC -- Integrated Gas Controller
SAT -- Supply Air Temperature

Marquee.

the IGC alert flash codes.

Check active alarms using ComfortLinkt Scrolling Marquee and
the IGC alert flash codes.

Check using ComfortLinkt Scrolling Marquee.

line of air, allow gas to dissipate for at least 5 minutes before
attempting to re---light unit.

the Service section.

SAT compared to the SAT heating limits.

position if needed using ComfortLink Scrolling Marquee. Verify
proper fan speed operation.

needed.
Check all screws around flue outlets and burner compartment.

Tighten as necessary.
Cracked heat exchanger, replace.
Unit is over---fired, reduce input. Adjust gas line or manifold

pressure.
Check vent for restriction. Clean as necessary.
Check orifice to burner alignment.

flash codes.

34

48/50PD

LEGEND

IDM -- Induced-Draft Motor
IGC -- Integrated Gas Unit Controller

NOTE: Thermostat Fan Switch in the
“AUTO” position.

C07014

Fig. 9 -- IGC Service Analysis Logic

35

Table 13 — IGC Board LED Alarm Codes

LED

FLASH

CODE

On Normal Operation
Off Hardware Failure No gas heating.

1Flash Indoor Fan On/Off Delay

2Flashes Limit Switch Fault Gas valve and igniter Off.

3Flashes Flame Sense Fault Indoor fan and inducer On. Flame sense normal.

4Flashes Four Consecutive Limit Switch

5Flashes Ignition Fault No gas heating. Heat call (W) Off.

48/50PD

6Flashes Induced Draft Motor Fault If heat off: no gas heating.

7Flashes Rollout Switch Lockout Gas valve and igniter Off.

8Flashes Internal Control Lockout No gas heating. Power reset. IGC has sensed internal hardware or software error.

9Flashes Temporary Software Lockout No gas heating. 1 hour auto reset, or

LEGEND

IGC -- Integrated Gas Unit Control
LED -- Light--Emitting Diode
NOTES:

1. There is a 3-- second pause between alarm code displays.

2. If more than one alarm code exists, all applicable alarm codes will be displayed in numerical sequence.

3. Alarm codes on the IGC will be lost if power to the unit is interrupted.

DESCRIPTION

Modified

Fault

ACTION TAKEN BY

CONTROL

RESET METHOD PROBABLE CAUSE

— — —

—

5 seconds subtracted from
On delay.
5 seconds added to Off
delay (3 min max).

Indoor fan and inducer On.

No gas heating. Heat call (W) Off.

If heat on: gas valve Off
and inducer On.

Indoor fan and inducer On.

Power reset. High temperature limit switch opens during heat

Limit switch closed, or
heat call (W) Off.

Power reset for LED reset.

Power reset for LED reset.

Power reset for LED reset.

Inducer sense normal, or
heat call (W) Off.

Power reset. Rollout switch has opened. Check gas valve

power reset.

Loss of power to the IGC. Check 5 amp fuse on
IGC, power to unit, 24V circuit breaker, transformer,
and wiring to the IGC.

exchanger warm-up period before fan-on delay
expires.
High temperature limit switch opens within
10 minutes of heat call (W) Off.
See Limit Switch Fault.

High temperature limit switch is open. Check the
operation of the indoor (evaporator) fan motor.
Ensure that the supply-air temperature rise is within
the range on the unit nameplate. Check wiring and
limit switch operation.

TheIGCsensedaflamewhenthegasvalveshould
be closed. Check wiring, flame sensor, and gas
valve operation.

4 consecutive limit switch faults within a single call
for heat. See Limit Switch Fault.

Unit unsuccessfully attempted ignition for 15 minutes.
Check igniter and flame sensor electrode spacing,
gaps,etc.Checkflamesenseandigniterwiring.
Check gas valve operation and gas supply.

Inducer sense On when heat call Off, or inducer
sense Off when heat call On. Check wiring, voltage,
and operation of IGC motor. Check speed sensor
wiring to IGC.

operation. Check induced-draft blower wheel is
properly secured to motor shaft.

If fault is not cleared by resetting 24 v power,
replace the IGC.

Electrical interference is disrupting the IGC
software.

Table 14 — Electric Heat Service Analysis

Heat Will Not Turn On. Unit is not configured for heat. Check heating configurations using ComfortLinkt

Inadequate Heating. Dirty air filters. Replace air filters.

Heat Will Not Turn Off. Unit is in minimum heat on---time. Check using ComfortLinkt Scrolling Marquee.

PROBLEM CAUSE REMEDY

Scrolling Marquee.

Marquee.

Check using ComfortLinkt Scrolling Marquee.

ServiceTestmodeoff.

switches on heater, and manual --- reset limit switches (LS)
on indoorfan housing.

replace if not.

resistance of element, replace if open.

check SAT compared to the SAT heating limits.

minimum position if needed using ComfortLinkt Scrolling
Marquee. Verify proper fan speed operation.

minimum airflow. Adjust as needed.

Check using ComfortLinkt Scrolling Marquee.

LEGEND
SAT -- Supply Air Temperature

Active alarm. Check active alarms using ComfortLink™ Scrolling

No power to unit. Check power supply, fuses, wiring, and circuit breakers.
Unit is in minimum heat off ---time, or minimum

cool--- heat changeover time.
Heat forced off in Service Test. Check using ComfortLinkt Scrolling Marquee. Turn

No 24 vac at heater contactor. Check transformer, circuit breaker, auto --- reset limit

Open temperature limit switch on heater. Check minimum airflow. Check limit switch when it is cool,

Bad heater elements. Power off unit and remove high voltage wires. Check

Occupancy schedule set point set too low. Check setpoints and adjust if necessary.
Heat undersized for load. Decrease load or increase size of heater.
Restricted or low airflow. Remove restriction, verify proper fan speed operation, and

Too much outdoor air. Check economizer position and configuration. Adjust

Limit switch cycles heaters. Check rotation of blower, temperature rise of unit, and

Occupancy schedule set point still calling for
Heating.

Unit running in Service Test mode. Check using ComfortLinkt Scrolling Marquee.
Heater contactor failed. Power off unit. Check contactor and replace if closed.

36

Thermistor Troubleshooting

The electronic control uses thermistors to sense temperatures used
to control operation of the unit. Resistances at various temperatures
are listed in Table 15-- 17. Thermistor pin connection points are
shown in the Major System Components section. The general
locations of the thermistors are shown the Major System
Components section.

Air Temperatures

Air temperatures are measured with 10 kilo-ohm thermistors. This
includes supply-air temperature (SAT), outdoor-air temperature
(OAT), space temperature sensors (T55, T56, T58), and return air
temperature (RAT).

The supply air temperature (SAT), return air temperature (RAT)
and outdoor air temperature (OAT) thermistors use a snap-mount to
attach through the unit sheet metal panels. The snap-mount tabs
must be flattened on the tip end of the sensor to release for removal
from the panel. (See Fig. 10.) To reinstall, make sure the
snap-mount tabs extend out.

C07015

Fig. 10 -- SAT, RAT and OAT Thermistor Mounting

Refrigerant Temperatures

Condenser coil temperatures are measured with 5 kilo-ohm
thermistors. These measurements provide an approximate saturated
condensing temperature for each circuit (SCT.A). Fig. 11 shows
the factory locations for the SCT thermistors on 48/50PD units.
Ensure that thermistors are placed at the correct location and are
snapped securely over the return bend so that contact is made
between the thermistor and the tube.

C07016

Fig. 11 -- Saturated Condensing Temperature Thermistor

Location

Thermistor/Temperature Sensor Check

A high quality digital volt-ohmmeter is required to perform this
check.

Connect the digital voltmeter across the appropriate thermistor
terminals at the J8 terminal strip on the Main Base Board (see
Major System Components section).

Using the voltage reading obtained, read the sensor temperature
from Table 15-- 17.

To check thermistor accuracy, measure temperature at probe
location with an accurate thermocouple-type
temperature-measuring instrument. Insulate thermocouple to avoid
ambient temperatures from influencing reading. Temperature
measured by thermocouple and temperature determined from
thermistor voltage reading should be close, within 5°F, if care was
taken in applying thermocouple and taking readings.

If a more accurate check is required, unit must be shut down and
thermistor removed and checked at a known temperature (freezing
point or boiling point of water) using either voltage drop measured
across thermistor at the J8 terminal, or by determining the
resistance with unit shut down and thermistor disconnected from
J8. Compare the values determined with the value read by the
control in the Temperatures mode using the Scrolling Marquee
display.

48/50PD

37

Sensor Trim

Corrective offsets can be applied to the space temperature and the
supply air temperature sensor readings. These corrections are set in
the Configuration→TRIM menu for the display, or in the
Maintenance→TRIM table for CCN. See the Indoor Air Quality
section for available adjustments to IAQ and OAQ sensor readings.
The space temperature may be corrected by entering either a
calibration temperature value in SPT.C, or an offset temperature
value in SPT.T. The supply-air temperature may be corrected by
entering either a calibration temperature value in SAT.C,oran
offset temperature value in SAT.T. The return--air temperature may
be corrected by entering either a calibration temperature value in
RAT.C or an offset temperature value in RAT.T. Temperature
corrections should only be made if sensor readings are compared to
an accurate reference temperature measurement device.

Transducer Troubleshooting

The electronic control uses suction pressure transducers to measure
the suction pressure of the refrigerant circuits. The pressure/voltage
characteristics of these transducers are in shown in Table 18, the
5vdc power is applied to legs A and B of the transducer and legs B

48/50PD

to C represent the voltage drop shown in the table. The accuracy of
these transducers can be verified by connecting an accurate
pressure gauge to the second refrigerant port in the suction line.

Forcing Inputs and Outputs

Many variables may have their value forced through CCN or
directly at the local display. This can be useful during diagnostic
testing and also during operation, typically as part of an advanced
third party control scheme. Input and output points that may be
forced are indicated as ‘forcible’ in the write status column of the
display and CCN tables.

If the user needs to force a variable, follow the same process as
when editing a configuration parameter. A forced variable will be
displayed on the Scrolling Marquee with a blinking period “.”
following its value. A forced value on Navigator™ accessory is
indicated with a blinking “f”. A forced value on CCN devices is
indicated with “Control” if forced at the unit display, or
“Supervisor” if forced via CCN. To remove a local force with the
Scrolling Marquee, select the point with the ENTER key and then
press the up -- arrow and down-arrow keys simultaneously.

IMPORTANT: In the case of a control power reset, any force in
effect at the time of power reset will be cleared.

38

Table 1 5 — Tempera t u re (_F) vs Resistance/Voltage Drop Values for

RAT, OAT, SAT, and SPT Thermistors (10K at 25_C Resistors)

TEMP VOLTAGE RESISTANCE TEMP VOLTAGE RESISTANCE TEMP VOLTAGE RESISTANCE

(F) DROP (V) (Ohms) (F) DROP (V) (Ohms) (F) DROP (V) (Ohms)

--- 2 5 4.758 196,453 61 2.994 14,925 147 0.890 2,166

--- 2 4 4.750 189,692 62 2.963 14,549 148 0.876 2,124

--- 2 3 4.741 183,300 63 2.932 14,180 149 0.862 2,083

--- 2 2 4.733 177,000 64 2.901 13,824 150 0.848 2,043

--- 2 1 4.724 171,079 65 2.870 13,478 151 0.835 2,003

--- 2 0 4.715 165,238 66 2.839 13,139 152 0.821 1,966

--- 1 9 4.705 159,717 67 2.808 12,814 153 0.808 1,928

--- 1 8 4.696 154,344 68 2.777 12,493 154 0.795 1,891

--- 1 7 4.686 149,194 69 2.746 12,187 155 0.782 1,855

--- 1 6 4.676 144,250 70 2.715 11,884 156 0.770 1,820

--- 1 5 4.665 139,443 71 2.684 11,593 157 0.758 1,786

--- 1 4 4.655 134,891 72 2.653 11,308 158 0.745 1,752

--- 1 3 4.644 130,402 73 2.622 11,031 159 0.733 1,719

--- 1 2 4.633 126,183 74 2.592 10,764 160 0.722 1,687

--- 1 1 4.621 122,018 75 2.561 10,501 161 0.710 1,656

--- 1 0 4.609 118,076 76 2.530 10,249 162 0.699 1,625

--- 9 4.597 114,236 77 2.500 10,000 163 0.687 1,594

--- 8 4.585 110,549 78 2.470 9,762 164 0.676 1,565

--- 7 4.572 107,006 79 2.439 9,526 165 0.666 1,536

--- 6 4.560 103,558 80 2.409 9,300 166 0.655 1,508

--- 5 4.546 100,287 81 2.379 9,078 167 0.645 1,480

--- 4 4.533 97,060 82 2.349 8,862 168 0.634 1,453

--- 3 4.519 94,020 83 2.319 8,653 169 0.624 1,426

--- 2 4.505 91,019 84 2.290 8,448 170 0.614 1,400

--- 1 4.490 88,171 85 2.260 8,251 171 0.604 1,375
0 4.476 85,396 86 2.231 8,056 172 0.595 1,350
1 4.461 82,729 87 2.202 7,869 173 0.585 1,326
2 4.445 80,162 88 2.173 7,685 174 0.576 1,302
3 4.429 77,662 89 2.144 7,507 175 0.567 1,278
4 4.413 75,286 90 2.115 7,333 176 0.558 1,255
5 4.397 72,940 91 2.087 7,165 177 0.549 1,233
6 4.380 70,727 92 2.059 6,999 178 0.540 1,211
7 4.363 68,542 93 2.030 6,838 179 0.532 1,190
8 4.346 66,465 94 2.003 6,683 180 0.523 1,169
9 4.328 64,439 95 1.975 6,530 181 0.515 1,148

10 4.310 62,491 96 1.948 6,383 182 0.507 1,128
11 4.292 60,612 97 1.921 6,238 183 0.499 1,108
12 4.273 58,781 98 1.894 6,098 184 0.491 1,089
13 4.254 57,039 99 1.867 5,961 185 0.483 1,070
14 4.235 55,319 100 1.841 5,827 186 0.476 1,052
15 4.215 53,693 101 1.815 5,698 187 0.468 1,033
16 4.195 52,086 102 1.789 5,571 188 0.461 1,016
17 4.174 50,557 103 1.763 5,449 189 0.454 998
18 4.153 49,065 104 1.738 5,327 190 0.447 981
19 4.132 47,627 105 1.713 5,210 191 0.440 964
20 4.111 46,240 106 1.688 5,095 192 0.433 947
21 4.089 44,888 107 1.663 4,984 193 0.426 931
22 4.067 43,598 108 1.639 4,876 194 0.419 915
23 4.044 42,324 109 1.615 4,769 195 0.413 900
24 4.021 41,118 110 1.591 4,666 196 0.407 885
25 3.998 39,926 111 1.567 4,564 197 0.400 870
26 3.975 38,790 112 1.544 4,467 198 0.394 855
27 3.951 37,681 113 1.521 4,370 199 0.388 841
28 3.927 36,610 114 1.498 4,277 200 0.382 827
29 3.903 35,577 115 1.475 4.185 201 0.376 814
30 3.878 34,569 116 1.453 4,096 202 0.370 800
31 3.853 33,606 117 1.431 4,008 203 0.365 787
32 3.828 32,654 118 1.409 3,923 204 0.359 774
33 3.802 31,752 119 1.387 3,840 205 0.354 762
34 3.776 30,860 120 1.366 3,759 206 0.349 749
35 3.750 30,009 121 1.345 3,681 207 0.343 737
36 3.723 29,177 122 1.324 3,603 208 0.338 725
37 3.697 28,373 123 1.304 3,529 209 0.333 714
38 3.670 27,597 124 1.284 3,455 210 0.328 702
39 3.654 26,838 125 1.264 3,383 211 0.323 691
40 3.615 26,113 126 1.244 3,313 212 0.318 680
41 3.587 25,396 127 1.225 3,244 213 0.314 670
42 3.559 24,715 128 1.206 3,178 214 0.309 659
43 3.531 24,042 129 1.187 3,112 215 0.305 649
44 3.503 23,399 130 1.168 3,049 216 0.300 639
45 3.474 22,770 131 1.150 2,986 217 0.296 629
46 3.445 22,161 132 1.132 2,926 218 0.292 620
47 3.416 21,573 133 1.114 2,866 219 0.288 610
48 3.387 20,998 134 1.096 2,809 220 0.284 601
49 3.357 20,447 135 1.079 2,752 221 0.279 592
50 3.328 19,903 136 1.062 2,697 222 0.275 583
51 3.298 19,386 137 1.045 2,643 223 0.272 574
52 3.268 18,874 138 1.028 2,590 224 0.268 566
53 3.238 18,384 139 1.012 2,539 225 0.264 557

54 3.208 17,904 140 0.996 2,488
55 3.178 17,441 141 0.980 2,439
56 3.147 16,991 142 0.965 2,391
57 3.117 16,552 143 0.949 2,343
58 3.086 16,131 144 0.934 2,297
59 3.056 15,714 145 0.919 2,253
60 3.025 15,317 146 0.905 2,209

48/50PD

39

Table 1 6 — Tempera t u re (_F) vs. Resistance/Voltage Drop Values for SCT Sensors (5K at 25_C Resistors)

TEMP

(F)

--- 2 5 3.699 98,010 59 1.982 7,866 143 0.511 1,190

--- 2 4 3.689 94,707 60 1.956 7,665 144 0.502 1,165

--- 2 3 3.679 91,522 61 1.930 7,468 145 0.494 1,141

--- 2 2 3.668 88,449 62 1.905 7,277 146 0.485 1,118

--- 2 1 3.658 85,486 63 1.879 7,091 147 0.477 1,095

--- 2 0 3.647 82,627 64 1.854 6,911 148 0.469 1,072

--- 1 9 3.636 79,871 65 1.829 6,735 149 0.461 1,050

--- 1 8 3.624 77,212 66 1.804 6,564 150 0.453 1,029

--- 1 7 3.613 74,648 67 1.779 6,399 151 0.445 1,007

--- 1 6 3.601 72,175 68 1.754 6,238 152 0.438 986

--- 1 5 3.588 69,790 69 1.729 6,081 153 0.430 965

--- 1 4 3.576 67,490 70 1.705 5,929 154 0.423 945

--- 1 3 3.563 65,272 71 1.681 5,781 155 0.416 925

--- 1 2 3.550 63,133 72 1.656 5,637 156 0.408 906

--- 1 1 3.536 61,070 73 1.632 5,497 157 0.402 887

--- 1 0 3.523 59,081 74 1.609 5,361 158 0.395 868

--- 9 3.509 57,162 75 1.585 5,229 159 0.388 850

--- 8 3.494 55,311 76 1.562 5,101 160 0.381 832

--- 7 3.480 53,526 77 1.538 4,976 161 0.375 815

--- 6 3.465 51,804 78 1.516 4,855 162 0.369 798

--- 5 3.450 50,143 79 1.493 4,737 163 0.362 782

--- 4 3.434 48,541 80 1.470 4,622 164 0.356 765

--- 3 3.418 46,996 81 1.448 4,511 165 0.350 750

--- 2 3.402 45,505 82 1.426 4,403 166 0.344 734

--- 1 3.386 44,066 83 1.404 4,298 167 0.339 719

48/50PD

10 3.185 31,202 94 1.179 3,318 178 0.282 581
11 3.165 30,260 95 1.160 3,243 179 0.277 570
12 3.145 29,351 96 1.141 3,170 180 0.272 561
13 3.124 28,473 97 1.122 3,099 181 0.268 551
14 3.103 27,624 98 1.104 3,031 182 0.264 542
15 3.082 26,804 99 1.086 2,964 183 0.259 533
16 3.060 26,011 100 1.068 2,898 184 0.255 524
17 3.038 25,245 101 1.051 2,835 185 0.251 516
18 3.016 24,505 102 1.033 2,773 186 0.247 508
19 2.994 23,789 103 1.016 2,713 187 0.243 501
20 2.972 23,096 104 0.999 2,655 188 0.239 494
21 2.949 22,427 105 0.983 2,597 189 0.235 487
22 2.926 21,779 106 0.966 2,542 190 0.231 480
23 2.903 21,153 107 0.950 2,488 191 0.228 473
24 2.879 20,547 108 0.934 2,436 192 0.224 467
25 2.856 19,960 109 0.918 2,385 193 0.220 461
26 2.832 19,393 110 0.903 2,335 194 0.217 456
27 2.808 18,843 111 0.888 2,286 195 0.213 450
28 2.784 18,311 112 0.873 2,239 196 0.210 445
29 2.759 17,796 113 0.858 2,192 197 0.206 439
30 2.735 17,297 114 0.843 2,147 198 0.203 434
31 2.710 16,814 115 0.829 2,103 199 0.200 429
32 2.685 16,346 116 0.815 2,060 200 0.197 424
33 2.660 15,892 117 0.801 2,018 201 0.194 419
34 2.634 15,453 118 0.787 1,977 202 0.191 415
35 2.609 15,027 119 0.774 1,937 203 0.188 410
36 2.583 14,614 120 0.761 1,898 204 0.185 405
37 2.558 14,214 121 0.748 1,860 205 0.182 401
38 2.532 13,826 122 0.735 1,822 206 0.179 396
39 2.506 13,449 123 0.723 1,786 207 0.176 391
40 2.480 13,084 124 0.710 1,750 208 0.173 386
41 2.454 12,730 125 0.698 1,715 209 0.171 382
42 2.428 12,387 126 0.686 1,680 210 0.168 377
43 2.402 12,053 127 0.674 1,647 211 0.165 372
44 2.376 11,730 128 0.663 1,614 212 0.163 367
45 2.349 11,416 129 0.651 1,582 213 0.160 361
46 2.323 11,112 130 0.640 1,550 214 0.158 356
47 2.296 10,816 131 0.629 1,519 215 0.155 350
48 2.270 10,529 132 0.618 1,489 216 0.153 344
49 2.244 10,250 133 0.608 1,459 217 0.151 338
50 2.217 9,979 134 0.597 1,430 218 0.148 332
51 2.191 9,717 135 0.587 1,401 219 0.146 325
52 2.165 9,461 136 0.577 1,373 220 0.144 318
53 2.138 9,213 137 0.567 1,345 221 0.142 311
54 2.112 8,973 138 0.557 1,318 222 0.140 304
55 2.086 8,739 139 0.548 1,291 223 0.138 297
56 2.060 8,511 140 0.538 1,265 224 0.135 289
57 2.034 8,291 141 0.529 1,240 225 0.133 282

58 2.008 8,076 142 0.520 1,214

VOLTAGE
DROP (V)

0 3.369 42,679 84 1.382 4,196 168 0.333 705
1 3.352 41,339 85 1.361 4,096 169 0.327 690
2 3.335 40,047 86 1.340 4,000 170 0.322 677
3 3.317 38,800 87 1.319 3,906 171 0.317 663
4 3.299 37,596 88 1.298 3,814 172 0.311 650
5 3.281 36,435 89 1.278 3,726 173 0.306 638
6 3.262 35,313 90 1.257 3,640 174 0.301 626
7 3.243 34,231 91 1.237 3,556 175 0.296 614
8 3.224 33,185 92 1.217 3,474 176 0.291 602
9 3.205 32,176 93 1.198 3,395 177 0.286 591

RESISTANCE

(Ohms)

TEMP (F)

VOLTAGE
DROP (V)

RESISTANCE

(Ohms)

TEMP (F)

VOLTAGE
DROP (V)

RESISTANCE

(Ohms)

40

Table 17 — Temperature vs Resistance Values for the DTT Thermistor

(86K at 25_C Resistors)

Degree C Degree F Resistance (k Ohms)

--- 4 0 --- 4 0 2889.60

--- 3 5 --- 3 1 2087.22

--- 3 0 --- 2 2 1522.20

--- 2 5 --- 1 3 1121.44

--- 2 0 --- 4 834.72

--- 1 5 5 627.28

--- 1 0 14 475.74

--- 5 23 363.99

0 32 280.82

5 41 218.41

10 50 171.17

15 59 135.14

20 68 107.44

25 77 86.00

30 86 69.28

35 95 56.16

40 104 45.81

45 113 37.58

50 122 30.99

55 131 25.68

60 140 21.40

65 149 17.91

Degree C Degree F Resistance (k Ohms)

70 158 15.07

75 167 12.73

80 176 10.79

85 185 9.20

90 194 7.87

95 203 6.77

100 212 5.85

105 221 5.09

110 230 4.45

115 239 3.87

120 248 3.35

125 257 2.92

130 266 2.58

135 275 2.28

140 284 2.02

145 293 1.80

150 302 1.59

155 311 1.39

160 320 1.25

165 329 1.12

170 338 1.01

175 347 0.92

180 356 0.83

48/50PD

41

Table 18 — Pressure (psig) vs. Voltage Drop Values for Suction Pressure Transducers

PRESSURE

(psig)

0
2
4
6

8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38

48/50PD

40
42
44
46
48
50
52
54
56
58
60
62
64
66

VOLTAGE
DROP (V)

0.465

0.485

0.505

0.524

0.544

0.564

0.583

0.603

0.623

0.642

0.662

0.682

0.702

0.721

0.741

0.761

0.780

0.800

0.820

0.839

0.859

0.879

0.898

0.918

0.938

0.958

0.977

0.997

1.017

1.036

1.056

1.076

1.095

1.115

PRESSURE

(psig)

68
70
72
74
76
78
80
82
84
86
88
90
92
94
96

98
100
102
104
106
108
110
112
114
116
118
120
122
124
126
128
130
132
134

VOLTAGE
DROP (V)

1.135

1.154

1.174

1.194

1.214

1.233

1.253

1.273

1.292

1.312

1.332

1.351

1.371

1.391

1.410

1.430

1.450

1.470

1.489

1.509

1.529

1.548

1.568

1.588

1.607

1.627

1.647

1.666

1.686

1.706

1.726

1.745

1.765

1.785

PRESSURE

(psig)

136
138
140
142
144
146
148
150
152
154
156
158
160
162
164
166
168
170
172
174
176
178
180
182
184
186
188
190
192
194
196
198
200
202

VOLTAGE
DROP (V)

1.804

1.824

1.844

1.863

1.883

1.903

1.922

1.942

1.962

1.982

2.001

2.021

2.041

2.060

2.080

2.100

2.119

2.139

2.159

2.178

2.198

2.218

2.237

2.257

2.277

2.297

2.316

2.336

2.356

2.375

2.395

2.415

2.434

2.454

PRESSURE

(psig)

204
206
208
210
212
214
216
218
220
222
224
226
228
230
232
234
236
238
240
242
244
246
248
250
252
254
256
258
260
262
264
266
268
270

VOLTAGE
DROP (V)

2.474

2.493

2.513

2.533

2.553

2.572

2.592

2.612

2.631

2.651

2.671

2.690

2.710

2.730

2.749

2.769

2.789

2.809

2.828

2.848

2.868

2.887

2.907

2.927

2.946

2.966

2.986

3.005

3.025

3.045

3.065

3.084

3.104

3.124

MAJOR SYSTEM COMPONENTS

General

The 48/50PD single package rooftop units contain the
ComfortLink™ electronic control system that monitors all
operations of the rooftop. The control system is composed of
several main control components and available factory-installed
options or field-installed accessories as listed in sections below.
See Fig. 12--14 for the control and power schematics for
48/50PD. Fig. 15 shows the layout of the control box, unit, and
thermistor and transducer locations for the 48/50PD.

42

48/50PD

Fig. 12 -- 48PD Control Wiring Schematic

43

C08582

48/50PD

Fig. 13 -- 50PD Control Wiring Schematic

44

C08583

48/50PD

Fig. 14 -- 48/50PD Power Wiring Schematic and Legend

45

C08584

48/50PD

Fig. 15 -- Typical Unit Component Arrangement

46

C08657

Main Base Board (MBB)

See Fig. 16 and Table 19. The MBB is the center of the
ComfortLink control system. It contains the major portion of the
operating software and controls the operation of the unit. The
MBB continuously monitors input/output channel information
received from its inputs and from the Economizer Control Board
(ECB). The MBB receives inputs from thermistors and transducers.

The MBB also receives the Current Sensor inputs for compressors
and other discrete or digital inputs. The MBB reads space

RED LED - STATUS GREEN LED -

CEPL130346-01

LEN (LOCAL EQUIPMENT NETWORK)

temperature (SPT) from either a T--55, T-- 56 or T-- 58 device and
space temperature offset (SPTO) from a T--56 device. See
Field-Installed Accessories section. The MBB controls 9 relays.

IMPORTANT: The Main Base Board (MBB) has a 3-position
instance jumper that is factory set to ‘1.’ Do not change this

setting.

YELLOW LED ­CCN (CARRIER COMFORT NETWORK)

INSTANCE JUMPER (SET TO 1)

J1

J6

J4

J5

J2

J3

J7

LEN

CCN

STATUS

J8

Fig. 16 -- Main Base Board (MBB)

48/50PD

J10

J9

C07026

47

Table 19 — MBB Connections

DISPLAY

NAME

Input power from TRAN1 control box 24 VAC J 1 , 1 --- 3
IGC Fan Request gas section switch input J6, 4

FDWN Fire shutdown switch supply/return/space switch input J6, 6

HUM Space Humidity switch space switch input J7, 4

DigitalScrollUnloader switch input J7, 6

C.ALM Scroll Compressor Alarm switch input J7, 8

CMP.A Compressor A Feedback switch input J7, 10

FIL.S Filter status switch indoor fan section switch input J 9 , 2 --- 3

CS.A1 Compressor A1 Current Sensor control box 0--- 5vdc digital input J 9 , 1 0 --- 1 2

SPT Space temperature (T55/56) space 10k thermistor J 8 , 1 --- 2

SPTO Space temperature offset (T56) space 10k thermistor J 8 , 2 --- 3

OAT Outdoor air temperature outdoor coil support 10k thermistor J 8 , 5 --- 6

SAT Supply air temperature

SCT.A Saturated condenser temperature, circuit A outdoor coil, circuit A 5k thermistor J 8 , 9 --- 1 0

RAT Return air temperature Return air Section 10k thermistor J 8 , 1 3 --- 1 4

48/50PD

FAN.S Fan status switch indoor fan section switch input J 8 , 1 5 --- 1 6

SSP.A Suction pressure, circuit A compressor A suction

CTLR DigitalScrollCtrlPwr relay J10, 11

CCH Crankcase heat relay relay J10, 13

OFC.1 Outdoor fan 1 relay relay J10, 19

IDF Indoor fan VFD pwr relay relay J10, 21

ALRM Alarm relay relay J10, 23

HT.1 Heat Stage 2 relay relay J10, 25
HT.2 Heat Stage 1 relay relay J10, 27

Local Equipment Network (LEN) communication J 5 , 1 --- 3
Carrier Comfort Network (CCN) communication J 5 , 5 --- 7
Network device power 24 VAC J5 , 9 --- 1 0
Scrolling Marquee Display (LEN) communication J 4 , 1 --- 3
Scrolling Marquee Display power 24 VAC J 4 , 5 --- 6
Modulation Board (AUX1) LEN communication J 3 , 1 --- 3
Optional ECB power 24 VAC J 2 , 1 --- 2

POINT DESCRIPTION SENSOR LOCATION TYPE OF I/O

INPUTS

indoor fan housing, or

supply duct

OUTPUTS

COMMUNICATION

10k thermistor J 8 , 7 --- 8

0 --- 5 V D C p r e s s u r e

transducer

CONNECTION

PIN NUMBER

J 8 , 1 8 --- 2 0

48

Economizer Control Board (ECB)

The ECB controls the economizer actuator. (See Fig. 17 and Table

20.) The control signal from the ECB uses either the MFT
(Multi-Function Technology) digital communication protocol or a
4 to 20 mA output signal as defined by the configuration
Configuration→ECON→E.CTL. The ECB has inputs for
Indoor Air Quality (IAQ), Outdoor Air Quality (OAQ), enthalpy
and RH sensor. It also controls two power exhaust outputs.

By digitally communicating with the ECB, the economizer
actuator is able to provide the damper position and diagnostic
information to the ComfortLink controller. The damper
position is displayed at Outputs→ECON→EC.AP. Diagnostic
information is displayed via Alert T414. More information about
these alarms is contained in the Alarms and Alerts section.

IMPORTANT: The Economizer Control Board (ECB) has a

4-position DIP switch that is factory set to ‘0’ (ON, towards

the center of the board). Do not change this setting.

48/50PD

Fig. 17 -- Economizer Control Board (ECB)

49

C07027

Table 2 0 — ECB Connections

DISPLAY

NAME

Input power from MBB control box 24 VAC J 1 , 1 --- 2
RM.OC Remote occupancy switch field installed switch input J4, 2
ENTH or

IAQ.S
IAQ Indoor air quality sensor return/space 0 --- 2 0 m A J5, 2
OAQ or

SP.RH

PE.1 Power exhaust 1 relay relay J8, 3
PE.2 Power exhaust 2 relay relay J8, 6
EC.CP Commanded Economizer position 0 --- 2 0 m A J9, 1

48/50PD

EC.CP &
EC.AP

Outdoor enthalpy switch, or

Indoor air quality switch

Outdoor air quality sensor, or

Relative humidity sensor

Sensor Common Ground J5, 3

Actuator Common Ground J7, 3

Output power to enthalpy switch 24 VAC J4, 3

Output power for loop power sensors 24 VDC J5, 1

Output power to economizer actuator 24 VAC J7, 2

Local Equipment Network (LEN) communication J 2 , 1 --- 3

Carrier Comfort Network (CCN) communication J3

Economizer actuator position

(digital control)

POINT DESCRIPTION SENSOR

LOCATION

INPUTS

economizer, or

return/space

field installed 0 --- 2 0 m A J5, 5

OUTPUTS

COMMUNICATION

TYPE OF I/O CONNECTION

switch input J4, 4

MFT

communication

PIN NUMBER

J7, 1

50

Modulation Board (AUX1)

The AUX1 board controls the compressor capacity and the indoor
fan speed (See Fig. 18 and Table 21.) It outputs a 1 -- 5vdc and a
2--10vdc signal to the DSC and VFD for capacity and fan speed,
respectively. This board is also used as the LEN connection buss

for the ECB, therefore must be operational for the ECB to
communicate.

IMPORTANT: The AUX1 board has an 8--position DIP switch
(S1) that is factory set for its LEN address. All the switches must
be in the off position except 4, 5 and 7 which are on (off is towards
the center of the board). Do not change this setting.

48/50PD

Fig. 18 -- Modulation Board (AUX1)

Table 21 — AUX1 Connections

DISPLAY

NAME

Input power from TRAN1 24 VAC J 1 , 1 1 --- 1 2
CAPC Compressor Capacity 1 --- 5 v d c CH9
F. S P D Commanded Fan Speed 2 --- 1 0 v d c CH10

Local Equipment Network (LEN) communication J9 , 1 --- 3

Local Equipment Network (LEN) communication J9 , 1 --- 3

POINT DESCRIPTION TYPE OF I/O

OUTPUTS

COMMUNICATION

CONNECTION

PIN NUMBER

C08658

51

Digital Scroll Control Board (DSC)

The DSC board controls the compressor’s capacity. (See Fig. 19
and Table 22.) It receives a 1--5vdc signal from the AUX1 board
determined by the cooling algorithm.

The DSC has direct control of the compressor and pulses a
solenoid unloader on and off to provide a specific capacity. The
discharge temperature thermistor (DTT) is monitored by the DSC
for compressor safety. The DSC is equipped with an LED
(light--emitting diode) for diagnostics. See the troubleshooting
section for more details.

48/50PD

Fig. 19 -- Digital Scroll Controller (DSC)

Table 22 — DSC Connections

DISPLAY

NAME

CTLR DigitalScrollCtrlPwr 24 VAC 24VAC/24COM

Compressor Discharge Temperature (DTT) Discharge line 86k thermistor T1/T2

CAPC Compressor Capacity 1 --- 5 v d c C1/C2

Load Control Power* 19--- 250VAC L1/L2

C.ALM Scroll Compressor Alarm Relay A1/A2
CMP.A Compressor A Feedback Relay M1/M2

DigitalScrollUnloader

* Voltage used for contacts M1 & M2, U1 & U2, and V1 & V2 (24 VAC used).

POINT DESCRIPTION

INPUTS

OUTPUTS

SENSOR

LOCATION

Compressor

section

TYPE OF I/O

Relay U1/U2

CONNECTION

PIN NUMBER

C08659

52

Variable Frequency Drive (VFD)

The VFD varies the frequency of the AC voltage supplied to the
indoor fan. (See Fig. 20 and Table 23.) This causes the variance in
the speed of the fan. The commanded fan speed is received by the
VFD from the AUX1 board as a 2--10vdc signal.

The AI1 DIP switch must be in the off (or towards “U”) position to
properly read the analog signal. There are three jumper wires that
must remain installed for proper operation. The VFD is mounted
behind the fan housing on the fan sled and the remote keypad is
mounted on the front of the fan housing for easy access. The VFD
is factory set to the auto mode for unit operation.

48/50PD

C09146

Fig. 20 -- Variable Frequency Drive (VFD)

Table 23 — VFD Connections

DISPLAY NAME POINT DESCRIPTION TYPE OF I/O

LOW VOLTAGE INPUTS

Shielded Cable Ground Shield 1 SCR

F. S P D Commanded Fan Speed 2 --- 1 0 v d c 2 AI1*

Analog Input 1 Common Ground 3 AGND
Low Voltage Power (jumped to DI1 & DI4) 24v 10 24v
Low Voltage Common (jumped to DCOM) Ground 11 GND
Discrete Inputs Common (jumped from GND) Ground 12 DCOM
Discrete Input 1 (jumped from 24v) Switch Input 13 DI1
Discrete Input 4 (jumped from 24v) Switch Input 16 DI4

HIGH VOLTAGE

V o l t a g e L e g f r o m I F C --- 2 1 Voltage Input U1 MAINS
V o l t a g e L e g f r o m I F C --- 2 2 Voltage Input V1 MAINS
V o l t a g e L e g f r o m I F C --- 2 3 Voltage Input W1 MAINS
V o l t a g e L e g t o I F M --- 3 Voltage Output U2 MOTOR
V o l t a g e L e g t o I F M --- 2 Voltage Output V2 MOTOR
V o l t a g e L e g t o I F M --- 1 Voltage Output W2 MOTOR

* Requires the Al1 dip switch to be in in the Off (or towards “U”) position.

TERMINAL

NUMBER

TERMINAL

NAME

53

Integrated Gas Control (IGC) Board

The IGC is provided on gas heat units. (See Fig. 21 and Table 24.)

The IGC is equipped with an LED (light-emitting diode) for
diagnostics. See the Troubleshooting section for more information.

The IGC controls the direct spark ignition system and monitors the
rollout switch, limit switch, and induced-draft motor Hall Effect
switch.

RED LED-STATUS

48/50PD

Fig. 21 -- Integrated Gas Control (IGC) Board

Table 24 — IGC Connections

TERMINAL

LABEL

RT, C Input power from TRAN 1 control box 24 VAC
SS Speed sensor gas section analog input J 1 , 1 --- 3
FS, T1 Flame sensor gas section switch input
W Heat stage 1 MBB 24 VAC J2, 2
RS Rollout switch gas section switch input J 2 , 5 --- 6
LS Limit switch gas section switch input J 2 , 7 --- 8
CS Centrifugal switch (not used) switch input J 2 , 9 --- 1 0

L1, CM Induced draft combustion motor gas section line VAC
IFO Indoor fan request control box relay J2, 1
GV (W1) Gas valve (heat stage 1) gas section relay J2, 12
GV (W2) Gas Valve (heat stage 2, from MBB) gas section Not on IGC

POINT DESCRIPTION SENSOR LOCATION TYPE OF I/O

INPUTS

OUTPUTS

CONNECTION

PIN NUMBER

C07028

54

Low Voltage Terminal S trip

(TB1)

This circuit board provides a connection point between the major
control boards and a majority of the field-installed accessories. (See

Fig. 22 -- Low--Voltage Terminal Board (LVTB)

Table 25 — Field Connection Terminal Strip

Fig. 22 and Table 25.) The circuit breakers for the low voltage
control transformers, interface connection for the Carrier Comfort
Network® (CCN) communication, and interface connection for the
Local Equipment Network (LEN) communications are also located
on the low voltage terminal strip.

C08660

48/50PD

TERMINAL

LABEL

1 24 VDC Sensor Loop power 24 VDC output J10, 17
2 IAQ Indoor air quality sensor return/space 4 --- 2 0 m A i n p u t J10, 16
3 Air quality & humidity sensor common Ground J10, 15

4

5 RM.OC Remote occupancy switch field installed 24 VAC input J10, 13
6 Switchpower(ENTH,RM.OC,IAQ.S) 24 VAC output J10, 11 --- 12

7

8* EC.CP

9 Economizer signal common Ground J10, 3 --- 5

10* EC.AP

R 24 VAC power 24 VAC output J11, 11---14
Y1 NOT USED J11,10
Y2 NOT USED J11, 9

W1 NOT USED J11, 7--- 8
W2 HUM Space Humidity Switch space 24 VAC input J11, 6

G NOT USED J11, 5
C 24 VAC common 24 VAC output J11, 2 ---4

X ALRM Alarm output (normally open) 24 VAC output J11, 1

FIRE

SHUTDOWN

1

FIRE

SHUTDOWN

2

T55

1 --- 2

T55

2 --- 3

FAN STATUS

1 --- 2
LEN Local Equipment Network (LEN) communication J 1 3 , 1 --- 3 , 4 --- 5

CCN Carrier Comfort Network (CCN) communication J 1 3 , 6 --- 8 , 4 --- 5

* Refer to Third Party Control section for more information

DISPLAY

NAME

OAQ or
SP.RH

ENTH or
IAQ.S

FDWN Fire shutdown switch 24 VAC output supply/return switch input J12, 7

FDWN Fire shutdown switch input supply/return switch input J12, 6

SPT Space temperature (T55/56) space 10k thermistor J12, 4---5

SPTO Space temperature offset (T56) space 10k thermistor J12, 3--- 4

POINT DESCRIPTION

Outdoor air quality sensor or
Relative humidity sensor

Outdoor enthalpy switch, or
Indoor air quality switch

Economizer commanded position
actuator (when in digital control)

Economizer position feedback (when
in analog control)

NOT USED J12, 1---2

SENSOR

LOCATION

field installed 4 --- 2 0 m A i n p u t J10, 14

economizer, or

return/space

economizer 2 --- 1 0 V D C o u t p u t J10, 6---8

economizer

TYPE OF I/O

24 VAC input J10, 9---10

communication

2 --- 1 0 V D C o u t p u t

CONNECTION

PIN NUMBER

J10, 1--- 2

55

Scrolling Marquee Display

This device is the keypad interface used to access rooftop
information, read sensor values, and test the unit. (See Fig. 23.)
The Scrolling Marquee display is a 4-key, 4-character, 16-segment
LED (light-emitting diode) display. Eleven mode LEDs are located
on the display as well as an Alarm Status LED. See Basic Control
Usage section for further details.

IMPORTANT: Conductors and drain wire must be 20 AWG
(American Wire Gauge) minimum stranded, tinned copper.
Individual conductors must be insulated with PVC, PVC/nylon,
vinyl, Teflon, or polyethylene. An aluminum/polyester 100% foil
shield and an outer jacket of PVC, PVC/nylon, chrome vinyl, or
Teflon with a minimum operating temperature range of -- 20_Cto
60_C is required. See Table below for acceptable wiring.

MANUFACTURER PART NO.

MODE

Run Status

Service Test

Temperature

Pressures

Setpoints

Inputs

Outputs

Configuration

Time Clock

Operating Modes

Alarms

48/50PD

Accessory Navigatort Display

The accessory hand-held Navigator display can be used with
48/50PD units. (See Fig. 24.) The Navigator display operates the
same way as the Scrolling Marquee device. The Navigator display
plugs into the LEN port on either TB or the ECB board.

Alarm Status

ESCAPE

ENTER

Fig. 23 -- Scrolling Marquee

C06320

It is important when connecting to a CCN communication bus that
a color-coding scheme be used for the entire network to simplify
the installation. It is recommended that red be used for the signal
positive, black for the signal negative and white for the signal
ground. Use a similar scheme for cables containing different
colored wires.

At each system element, the shields of its communication bus
cables must be tied together. The shield screw on TB1 can be used
to tie the cables together. If the communication bus is entirely
within one building, the resulting continuous shield must be
connected to a ground at one point only. The shield screw on TB1
is not acceptable for grounding. If the communication bus cable
exits from one building and enters another, the shields must be

Alpha

Belden

Carol

West Penn

2413 or 5463

8772

C2528

302

connected to grounds at the lightning suppressor in each building

C

o

m

f

o

r

t

L

N

in

A

V

I

k

G

A

T

O

T

IM

E

W

L

W

T

S

E

T

R

E

1

2

T

.

5

8

5

4

.

6

°

F

4

4

P

.1

°

F

4

4

.

0

°

F

where the cable enters or exits the building (one point per building
only). To connect the unit to the network:

1. Turn off power to the control box.

2. Cut the CCN wire and strip the ends of the red (+), white
(ground), and black (--) conductors. (Substitute appropriate

M

O

D

E

Ala

rm

Ru

Sta

n Sta

tus

tu

s

S

e

rv

ice

Te

s

t

T

em

p

era

ture

s

P

res

s

ure

s

S

e

tpo

in

ts

In

pu

ts

O

utp

uts

C

on

fig

u

ra

tion

T

im

e C

lo

ck

E

O

S

p

er

C

ating

M

od

es

A

la

rm

s

E

N

T

E

R

colors for different colored cables.)

3. Connect the red wire to (+) terminal on TB1, the white wire
to COM terminal, and the black wire to the (--) terminal.

4. The RJ14 CCN connector on TB1 can also be used, but is
only intended for temporary connection (for example, a
laptop computer running Carrier network software).

5. Restore power to unit.

IMPORTANT: A shorted CCN bus cable will prevent some
routines from running and may prevent the unit from starting. If
abnormal conditions occur, unplug the connector. If conditions
return to normal, check the CCN connector and cable. Run new

C06321

Fig. 24 -- Accessory Navigatort Display

Carrier Comfort Network (CCN)R Interface

The units can be connected to the CCN if desired. The
communication bus wiring is a shielded, 3-conductor cable with
drain wire and is field supplied and installed. The system elements
are connected to the communication bus in a daisy chain
arrangement. (See Fig. 25.) The positive pin of each system
element communication connector must be wired to the positive
pins of the system elements on either side of it. This is also
required for the negative and signal ground pins of each system
element. Wiring connections for CCN should be made at TB. (See
Fig. 25.) Consult the CCN Contractor’s Manual for further
information.

cable if necessary. A short in one section of the bus can cause
problems with all system elements on the bus.

Field-Installed Accessories

Space Temperature Sensor (T--55)

The T--55 space temperature sensor (part no. 33ZCT55SPT) is a
field-installed accessory. The sensor is installed on a building
interior wall to measure room air temperature. The T--55 sensor
also includes an override button on the front cover to permit
occupants to override the Unoccupied Schedule (if programmed).

TB1--T55--1 Sensor Input........

TB1--T55 -- 2 Sensor Common........

Space Temperature Sensor (T--56)

The T--56 space temperature sensor (part no. 33ZCT56SPT) is a
field-installed accessory. This sensor includes a sliding scale on the
front cover that permits an occupant to adjust the space temperature
set point remotely. The T-- 56 sensor also includes an override
button on the front cover to allow occupants to override the
unoccupied schedule (if programmed).

TB1--T55--1 Sensor Input........

TB1--T55 -- 2 Sensor Common........

TB1--T55--3 Setpoint Offset Input........

56

Space Temperature Sensor (T--58)

The T--58 space temperature sensor (part no. 33ZCT58SPT) is a
field-installed accessory. The T-- 58 sensor communicates with the
ComfortLink™ controller, providing space temperature, heating
and cooling set points, and mode operation information.

Refer to the T--58 installation instructions for information on
installing and configuring the T-- 58 sensor.

CCN BUS

Each T--58 sensor must have a unique address on the CCN. Each
T--58 sensor must also be configured with the address of the unit
control it is communicating to.

Space Temperature Sensor Averaging

See Fig. 26 for space temperature averaging with T -- 55 sensors
only. If the use of one T--56 sensor is required, refer to Fig. 27.

REMOTE
CCN SITE

BUILDING SUPERVISOR

NETWORK
OPTIONS

AUTODIAL
GATEWAY

TERMINAL
SYSTEM
MANAGER

CL

CL

ROOFTOP
UNIT

ROOFTOP
UNIT

CL

ROOFTOP
UNIT

HEATING/COOLING UNITS

TCU

DAV AIR
TERMINAL

TCU

DAV AIR
TERMINAL

CL

CL

ROOFTOP
UNIT

ROOFTOP
UNIT

TCU

LEGEND
CCN -- Carrier Comfort Networkr
CL -- ComfortLinkt Controls
DAV -- Digital Air Volume
HVAC -- Heating, Ventilation, and
Air Conditoning
TCU -- Terminal Control Unit

TO
ADDITIONAL
TERMINALS

DAV FAN
POWERED
MIXING
BOX

48/50PD

NON CARRIER
HVAC
EQUIPMENT

COMFORT

CONTROLLER

AIR DISTRIBUTION-DIGITAL AIR VOLUME CONTROL (DAV)

C07030

Fig. 25 -- CCN System Architecture

57

RED

T

BLK

RED

BLK

TB1-T55

1

2

TO MAIN
BASE BOARD

RED

BLK

SENSOR 1 SENSOR 2 SENSOR 3 SENSOR 4

RED

BLK

RED

BLK

SPACE TEMPERATURE AVERAGING --4 T-55 SENSOR APPLICATION

TB1-T55

1

48/50PD

2

TO MAIN
BASE BOARD

RED

BLK

BLK

SENSOR 1

RED

RED

BLK

SENSOR 2

RED

BLK

SENSOR 3

LEGEND

B -- Terminal Block
______ -- Factory Wiring
_ _ _ _ -- Field Wiring

RED

BLK

RED

BLK

SENSOR 6SENSOR 5

BLK

SENSOR 4

RED

RED

BLK

RED

BLK

SENSOR 8SENSOR 7 SENSOR 9

SPACE TEMPERATURE AVERAGING --9 T-55 SENSOR APPLICATION

C07032

Fig. 26 -- Space Temperature Sensor Averaging

RED

BLK

TB1-T55

1

2

TO MAIN

BASE

BOARD

RED

BLK

RED

BLK

RED

BLK

RED

BLK

TB1-T55

3

TO MAIN

BASE

BOARD

T-55 SENSOR 1 T-55 SENSOR 2 T-55 SENSOR 3 T-56 SENSOR 4

WHT

C07033

Fig. 27 -- Space Temperature Sensor Averaging with 3 T--55 Sensors and One T--56 Sensor

58

Carrier Accessory Kits

There are specific accessory kits sold for various field installed
accessories. These kits vary based on model, size, voltage,
manufacture date, and duct orientation. Some of these kits include
Economizer, Power Exhaust, and Electric Heat. Refer to the
Controls Quick Set--Up section for configuration and more
information on these accessories.

Two--Position Damper

The two-position outdoor air damper accessory usage depends on
model size and return duct orientation. This accessory wires
directly into the low voltage circuit for the indoor fan control. No
other control configuration is needed.

Indoor Air Quality

The indoor air quality (IAQ) sensor (part no. 33ZCSENCO2) is a
field-installed accessory which measures CO
When installing this sensor, an ECB board must be installed and
the unit must be configured for IAQ use by setting
Configuration→AIR.Q→IA.CF to a value of 1, 2, or 3. See the
Indoor Air Quality section for more information.

TB1--2 4--20 mA Input.......

TB1--3 Sensor Common.......

TB1--R 24 VAC Output......

TB1--C Common (GND)......

levels in the air.

2

Outdoor Air Quality

The outdoor air quality (OAQ) sensor is a field-installed accessory
that measures CO
ECB board must be installed and the unit must be configured for
OAQ use by setting Configuration→AIR.Q→OA.CF to a value
of 1 or 2. See the Indoor Air Quality section for more information.

TB1--4 4--20 mA Input.......

TB1--3 Sensor Common.......

TB1--R 24 VAC Output......

TB1--C Common (GND)......

levels in the air. When installing this sensor, an

2

Smoke Detectors

The smoke detectors are field-installed accessories. These detectors
can detect smoke in either the return air (part no.
CRSMKDET003A00) or supply and return air (part no.
CRSMKSUP002A00). When installing either detector, the unit
must be configured for fire shutdown by setting
Configuration→UNIT→FS.SW to normally open (1) or normally
closed (2).

TB1--Fire Shutdown--1 Dry Contact Source....

TB1--Fire Shutdown--2 Discrete Input to Board....

TB1--R 24 VAC Output................

TB1--C Common (GND)................

Filter Status

The filter status accessory (part no. CRSTATUS002B00) is a
field-installed accessory. This accessory detects plugged filters.
When installing this accessory, the unit must be configured for
filter status by setting Configuration→UNIT→FL.SW to
normally open (1) or normally closed (2). Normally open (1) is the
preferred configuration. Filter status wires are pre-run in the unit
harness and located near the switch installation location. Refer to
the Filter Accessory Installation Instructions for more information.

Fan Status

The fan status accessory (part no. CRSTATUS003B00) is a
field-installed accessory. This accessory detects when the indoor
fan is blowing air. When installing this accessory, the unit must be
configured for fan status by setting
Configuration→UNIT→FN.SW to normally open (1) or
normally closed (2). Normally open (1) is the preferred
configuration. Fan status wires are pre-run in the unit harness and
located near the switch installation location. Refer to the Fan
Accessory Installation Instructions for more information.

IMPORTANT: The Fan Status terminals on TB1 are NOT to be
used.

Enthalpy Sensors

The enthalpy accessories (part no. CRENTSNG002A00 and
CRENTDIF002A00) are field-installed accessories. The first
accessory (outdoor air only) determines when the enthalpy is low
relative to a fixed reference. Adding the second accessory (return
air) compares the enthalpy between the outdoor and return
airstreams. In each case, the enthalpy 4 to 20 mA signals are
converted to a switch output which is read by the ECB. When
installing this accessory, the unit must be configured for
enthalpy-based control by setting
Configuration→ECON→EN.SW to normally open (1). Normal
status is an active switch which tells the control that enthalpy is
LOW. The actual switch terminal LOW is normally closed. Refer
to the Enthalpy Kit Installation Instructions for more information
on its installation.

Return/Supply Air Temperature Sensor

The temperature sensor (part no. 33ZCSENSAT) is a field-installed
accessory which may be installed on the common return air duct
and/or the common supply air duct near the unit. The duct supply
air temperature (SAT) may be used to replace the SAT sensor that
is internal to the unit. A supply duct SAT measurement is valid for
heating mode display while the factory-standard internal SAT is
not valid for heating due to its location upstream of the heating
section. When installing the supply duct SAT, the unit must be
configured by setting Configuration→UNIT→SAT.H to ENBL.
A SAT sensor in the supply duct is the preferred configuration for
systems with Carrier variable volume and temperature (VVT®)
accessory controls.

Space Humidistat

The Space Humidistat (part no. -- --HL ----38MG--029) is a wall
mounted device with an adjustable setpoint to control humidity
levels. The humidistat input is provided on the field connection
terminal board. The Space Humidity Switch configuration,

→

Configuration

normally closed status of this input at LOW humidity.

TB1--R 24 VAC Dry Contact Source......

TB1--W2 Discrete Input to Board.....

UNIT→RH.SW, identifies the normally open or

Space Humidity Sensor

The space relative humidity sensor (part no. 33ZCSENDRH--01
duct mount or 33ZCSENSRH--01 wall mount) is a field--installed
accessory. The space relative humidity (RHS) may be selected for
use if the outdoor air quality sensor (OAQ) is not used and an
economizer board is installed. When installing the relative
humidity sensor, the unit must be configured by setting

→

Configuration

TB1--1 24 VDC Loop Power.......

TB1--4 4--20 mA Input Signal.......

UNIT→RH.S to YES.

SERVICE

!

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause personal
injury or death.

Before performing service or maintenance operations
on unit, turn off main power switch to unit and install
lockout tag. Ensure electrical service to rooftop unit
agrees with voltage and amperage listed on the unit
rating plate.

59

48/50PD

Remove Surface Loaded Fibers

!

WARNING

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause personal
injury, death and/or equipment damage.

Puronr (R-- 410A) refrigerant systems operate at higher
pressures than standard R-- 22 systems. Do not use R--22
service equipment or components on Puron refrigerant
equipment.

!

WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

1. Improper installation, adjustment, alteration, service,
or maintenance can cause property damage, personal

48/50PD

injury, or loss of life. Refer to the User’s Information

Manual provided with this unit for more details.

2. Do not store or use gasoline or other flammable

vapors and liquids in the vicinity of this or any other

appliance.

What to do if you smell gas:

1. DO NOT try to light any appliance.

2. DO NOT touch any electrical switch, or use any
phone in your building.

3. IMMEDIATELY call your gas supplier from a

neighbor’s phone. Follow the gas supplier’s

instructions.

4. If you cannot reach your gas supplier, call the fire

department.

!

WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury or death.

Disconnect gas piping from unit when pressure testing at
pressure greater than 0.5 psig. Pressures greater than

0.5 psig will cause gas valve damage resulting in hazardous
condition. If gas valve is subjected to pressure greater than

0.5 psig, it must be replaced before use. When pressure
testing field-supplied gas piping at pressures of 0.5 psig or
less, a unit connected to such piping must be isolated by
closing the manual gas valve(s).

Surface loaded fibers or dirt should be removed with a vacuum
cleaner. If a vacuum cleaner is not available, a soft non-metallic
bristle brush may be used. In either case, the tool should be applied
in the direction of the fins. Coil surfaces can be easily damaged (fin
edges can be easily bent over and damage to the coating of a
protected coil) if the tool is applied across the fins.

IMPORTANT: Use of a water stream, such as a garden hose,
against a surface loaded coil will drive the fibers and dirt into the
coil. This will make cleaning efforts more difficult. Surface loaded
fibers must be completely removed prior to using low velocity
clean water rinse.

Periodic Clean Water Rinse

A periodic clean water rinse is very beneficial for coils that are
applied in coastal or industrial environments. However, it is very
important that the water rinse is made with very low velocity water
stream to avoid damaging the fin edges. Monthly cleaning as
described below is recommended.

Routine Cleaning of Round--Tube Coil Surfaces

Monthly cleaning with Totaline® environmentally sound coil
cleaner is essential to extend the life of coils. This cleaner is
available from Carrier Replacement parts division as part number
P902--0301 for a one gallon container, and part number
P902--0305 for a 5 gallon container. It is recommended that all
round--tube coils, including standard aluminum, pre-coated,
copper/copper or E-coated coils be cleaned with the Totaline
environmentally sound coil cleaner as described below. Coil
cleaning should be part of the unit’s regularly scheduled
maintenance procedures to ensure long life of the coil. Failure to
clean the coils may result in reduced durability in the environment.

Avoid the use of:

S coil brighteners
S acid cleaning prior to painting
S high pressure washers
S poor quality water for cleaning

Totaline environmentally sound coil cleaner is non-flammable,
hypoallergenic, non--bacterial, and a USDA accepted
biodegradable agent that will not harm the coil or surrounding
components such as electrical wiring, painted metal surfaces, or
insulation. Use of non-recommended coil cleaners is strongly
discouraged since coil and unit durability could be affected.

Totaline Environmentally Sound Coil Cleaner Application
Equipment

1

/2gallon garden sprayer

S 2
S water rinse with low velocity spray nozzle

!

CAUTION

Cleaning

Inspect unit interior at beginning of each heating and cooling
season and as operating conditions require. Remove unit top panel
and/or side panels for access to unit interior.

Coil Maintenance and Cleaning Recommendation

Routine cleaning of coil surfaces is essential to maintain proper
operation of the unit. Elimination of contamination and removal of
harmful residues will greatly increase the life of the coil and extend
the life of the unit. The following maintenance and cleaning
procedures are recommended as part of the routine maintenance
activities to extend the life of the coil.

UNIT DAMAGE HAZARD

Failure to follow this caution may result in corrosion and
damage to the unit.

Harsh chemicals, household bleach or acid or basic cleaners
should not be used to clean outdoor or indoor coils of any
kind. These cleaners can be very difficult to rinse out of the
coil and can accelerate corrosion at the fin/tube interface
where dissimilar materials are in contact. If there is dirt
below the surface of the coil, use the Totaline
environmentally sound coil cleaner as described above.

60

!

CAUTION

UNIT RELIABILITY HAZARD

Failure to follow this caution may result in reduced unit
performance.

High velocity water from a pressure washer, garden hose, or
compressed air should never be used to clean a coil. The
force of the water or air jet will bend the fin edges and
increase airside pressure drop.

Totaline Environmentally Sound Coil Cleaner Application
Instructions

1. Proper eye protection such as safety glasses is
recommended during mixing and application.

2. Remove all surface loaded fibers and dirt with a vacuum
cleaner as described above.

3. Thoroughly wet finned surfaces with clean water and a low
velocity garden hose, being careful not to bend fins.

4. Mix Totaline environmentally sound coil cleaner in a

1

/2gallon garden sprayer according to the instructions

2
included with the cleaner. The optimum solution
temperature is 100_F.

IMPORTANT: Do NOT USE water in excess of 130_F, as th e
enzymatic activity will be destroyed.

5. Thoroughly apply Totaline® environmentally sound coil
cleaner solution to all coil surfaces including finned area,
tube sheets and coil headers.

6. Hold garden sprayer nozzle close to finned areas and apply
cleaner with a vertical, up-and-down motion. Avoid
spraying in horizontal pattern to minimize potential for fin
damage.

7. Ensure cleaner thoroughly penetrates deep into finned
areas.

8. Interior and exterior finned areas must be thoroughly
cleaned.

9. Finned surfaces should remain wet with cleaning solution
for 10 minutes.

10. Ensure surfaces are not allowed to dry before rinsing.
Reapplying cleaner as needed to ensure 10-minute
saturation is achieved.

11. Thoroughly rinse all surfaces with low velocity clean water
using downward rinsing motion of water spray nozzle.
Protect fins from damage from the spray nozzle.

Condensate Drain Pan

Check and clean each year at the start of the cooling season. In
winter, keep drains and traps dry.

To clean the condensate pan:

1. Disconnect condensate drain system from side or bottom
drain connection.

2. Remove and clean trap.

3. Remove 4 screws securing condensate pan access cover to
unit. Save screws and panel.

4. Slide condensate pan out from unit and clean. Pan is made
of non-corrosive plastic. Use a mild cleaner to remove
heavy deposits of dirt and grime.

5. Replace pan in unit.

6. Replace condensate pan access cover with 4 screws saved
from Step 3.

7. Re-attach and prime condensate trap.

8. Connect condensate drainage system.

ROLLOUT
SWITCH

HEAT EXCHANGER
SECTION

MAIN BURNER SECTION

INDUCED
DRAFT
MOTOR

COMBUSTION
FAN HOUSING

MAIN GAS
VALVE

C07037

Fig. 28 -- Typical Gas Heating Section

Filters

Clean or replace at start of each heating and cooling season, or
more often if operating conditions require. Refer to unit Installation
Instructions for type and size.

Outdoor--Air Inlet Screens

Clean screens with steam or hot water and a mild detergent. Do
not use throwaway filters in place of screens. See unit installation
instructions for quantity and size.

Main Burner (48PD)

At the beginning of each heating season, inspect for deterioration
or blockage due to corrosion or other causes. Observe the main
burner flames. Refer to Main Burners section.

Flue Gas Passageways (48PD)

The flue collector box and heat exchanger cells may be inspected
by opening heat section access door, flue box cover, and main
burner assembly. (See Fig. 28.) Refer to Main Burners section for
burner removal sequence. If cleaning is required, clean tubes with a
wire brush. Use Caution with ceramic heat exchanger baffles.
When installing retaining clip, be sure the center leg of the clip
extends inward toward baffle. (See Fig. 29.)

CERAMIC
BAFFLE

CLIP

NOTE: One baffle and clip will be in each upper tube of the heat exchanger.

C07260

Fig. 29 -- Removing Heat Exchanger Ceramic

Baffles and Clips

Combustion--Air Blower (48PD)

Clean periodically to assure proper airflow and heating efficiency.
Inspect blower wheel every fall and periodically during heating
season. For the first heating season, inspect blower wheel
bi-monthly to determine proper cleaning frequency.

61

48/50PD

To inspect blower wheel, open heat section door. Using a
flashlight, look into the flue exhaust duct to inspect. If cleaning is
required, remove motor and wheel assembly by removing the
screws holding the flue box cover to the flue box. Remove the
screws holding the inducer housing to the inlet plate. The wheel
can then be removed from the motor shaft and cleaned with a
detergent or solvent. Replace the wheel onto the motor shaft in the
correct position and reassemble the flue cover onto the flue box.

Lubrication

Compressors

Each compressor is charged with the correct amount of oil at the
factory.

!

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in damage to unit
components.

The compressor is in a Puron refrigerant system and uses a

48/50PD

polyolester (POE) oil. This oil is extremely hygroscopic,
meaning it absorbs water readily. POE oils can absorb 15
times as much water as other oils designed for HCFC and
CFC refrigerants. Avoid exposure of the oil to the
atmosphere.

Polyolester (POE) compressor lubricants are known to cause long
term damage to some synthetic roofing materials. Exposure, even if
immediately cleaned up, may cause roofing materials to become
brittle (leading to cracking) within a year. When performing any
service which may risk exposure of compressor oil to the roof, take
appropriate precautions to protect roofing. Procedures which risk
oil leakage include compressor replacement, repairing refrigerant
leaks, and replacing refrigerant components. To prepare rooftop:

1. Cover extended roof work area with an impermeable plastic
dropcloth or tarp. Make sure a 10 x 10 ft area around the
work area is covered.

2. Cover area in front of the unit service panel with a terry
cloth shop towel to absorb lubricant spills and prevent
run-offs. Towel will also protect dropcloth from tears caused
by tools or components.

3. Place terry cloth shop towel inside the unit directly under
components to be serviced to prevent spills through the
bottom of the unit.

4. Perform the required service.

5. Remove an dispose of any oil contaminated material per
local codes.

Indoor Fan Shaft Bearings

The indoor fan has permanently sealed bearings. No field
lubrication is necessary.

Condenser and Evaporator--Fan Motor Beari ngs

The condenser-fan and evaporator-fan motors have permanently
sealed bearings, so no field lubrication is necessary.

Economizer or Manual Outside Air Damper

If blade adjustment is required, refer to unit or accessory
installation instructions.

Evaporator Fan Service and Replacement

The units feature a slide-out fan deck for easy servicing of the
indoor-fan motor, pulleys, belt, bearings and VFD. To service
components in this section, perform the following procedure:

1. Turn off unit power.

2. Open the fan section access door.

3. Remove two no. 10 screws at front of slide-out fan deck.
Save screws. (See Fig. 30.)

4. Disconnect the electrical wires connected to the slide--out
fan deck (supply air thermistor and fan status switch if
installed). Wires may be damaged if not disconnected.

5. Fan deck can now be slid out to access serviceable
components.

!

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in damage to the
unit.

DO NOT SLIDE FAN DECK OUT PAST THE FAN
DECK STOP. If further access is required, the fan deck
must be supported. Make sure plugs and wiring are not
pinched between fan housing and unit sheet metal post.

6. To replace fan deck to operating position, slide fan deck
back into the unit. Secure with the two no. 10 screws
removedinStep3.

7. Re-attach electrical wires.

8. Close fan section access door.

9. Restore power to unit.

C08661

Fig. 30 -- Evaporator--Fan Motor Adjustment

Evaporator Fan Performance Adjustment

Fan motor pulleys are factory set for speed shown in Appendix D.
To change fan speeds:

1. Shut off unit power supply.

2. Loosen nuts on the 4 carriage bolts in the mounting base.
Using adjusting bolts and plate, slide motor and remove
belt.

3. Loosen movable-pulley flange setscrew. (See Fig. 31.)

4. Screw movable flange toward fixed flange to increase speed
and away from fixed flange to decrease speed. Increasing
fan speed increases load on motor. Do not exceed maximum
speed specified in Appendix D.
See Appendix D for air quantity limits.

5. Set movable flange at nearest keyway of pulley hub and
tighten setscrew. (See Appendix D for speed change for
each full turn of pulley flange.)

6. Replace belts.

62

7. Realign fan and motor pulleys:

a. Loosen fan pulley setscrews.

b. Slide fan pulley along fan shaft.

c. Make angular alignment by loosening motor from

mounting plate.

8. Tighten belts.

9. Restore power to unit.

C06041

Fig. 31 -- Evaporator--Fan Alignment and Adjustment

Evaporator Fan B elt Tension Adjustment

To adjust belt tension:

1. Turn off unit power.

2. Slide out fan deck to service position as shown in
Evaporator Fan Service and Replacement section above.

3. Loosen motor mounting plate bolts.

4. Move motor mounting plate to adjust to proper belt tension.
Motor adjuster bolts may be used to tighten belts. (See Fig.

30.) Do not overtighten belt.

5. Check for proper belt alignment. Adjust if necessary.

6. Tighten motor mounting plate bolts to lock motor in proper
position.

7. Return fan deck back into operating position.

8. Restore power to unit.

Variable Frequency Drive (VFD) Replacement

The 48/50PD units are equipped with a VFD that is mounted
behind the blower housing on the fan sled. The VFD’s remote
display is mounted on the front of the fan housing for easier access.
The VFD is mounted to a plate which is mounted to the fan sled.
When accessing the VFD or to remove the VFD, follow the
Evaporator fan service and replacement Steps 1--5 and the
following steps:

IMPORTANT: If fan deck stop screws are removed for further
access, the front of the fan deck MUST BE SUPPORTED.

1. Remove the 2 screws holding the VFD’s mount bracket to
the fan sled. The horizontal cross section of the bottom half
of the mount bracket is shown on Fig. 32.

2. Cut the wire ties holding the VFD power wires to the fan
housing and the two wire ties holding the control wires to
the VFD display/keypad at the top of the fan scroll.

3. With the VFD still attached, remove the mount bracket from
the fan sled. To do this requires a slight lift on the screw
side then a push towards the pulley side of the fan sled.

(See Fig. 32.) Lift out the bracket when the pulley side is
clear from the fan sled.

4. With all the wires stilled attached to the VFD, turn the VFD
assembly so it is parallel with the fan sled.

5. Pull the VFD assembly to the front of the fan sled and place
in a secure flat surface.

6. Disconnect the power, ground, RJ45, and control wiring to
the VFD making sure to note their connections.

IMPORTANT: Wires are marked with VFD terminal labels and
wiring diagram shows the wiring connections.

7. Remove the 4 screws holding the VFD to the mount bracket
and remove the VFD.

8. Remove the replacement VFD cover and install jumper
wires provided with it as shown on the unit wiring diagram.
If jumpers are not provided with the replacement VFD,
remove them from the defective one or field supply the
jumpers.

9. Set AI1 and AI2 DIP switches to the U (off) direction as
indicated on the plastic housing near the DIP switch.

10. Replace the VFD with the new one.

11. Install the 4 screws in the VFD to secure it to the mounting
bracket.

12. Connect the wiring as it was on the previous VFD, refer to
the wiring diagram.

13. Move the VFD assembly to the back of the fan sled.

14. Turn the VFD assembly lengthwise with the fan housing,
making sure the screw side of the bracket lines up with the
screw holes on the fan sled.

15. Make sure the bracket s pulley side U bend is clear of the
fan sled and pull the assembly towards the screw side.

16. Install the 2 screws in the bracket to secure it to the fan sled.

17. Secure power and control wires with new wire ties.

18. Follow the Evaporator fan service and replacement Steps
6--9.

19. Power up VFD and set up its parameters per Table 40 in
Appendix B.

IMPORTANT: If fan deck stops were removed, they must be
reinstalled.

For VFD service and maintenance, refer to Appendix B.

C08662

Fig. 32 -- VFD Mount Bracket Cross Section

Condenser-Fan Adjustment

1. Shut off unit power supply.

2. Remove condenser-fan assembly (grille, motor, motor
cover, and fan) and loosen fan hub setscrews.

3. Adjust fan height as shown in Fig. 33.

4. Tighten setscrews and replace condenser-fan assembly.

5. Turn on power to unit.

48/50PD

63

T

3. Connect a nitrogen cylinder and regulator to system and
open until system pressure is 2 psig.

4. Close service valve and allow system to stand for 1 hr.
During this time, dry nitrogen will be able to diffuse
throughout the system, absorbing moisture.

C08570

Fig. 33 -- Condenser--Fan Adjustment

5. Repeat this procedure. System will then contain minimal
amounts of contaminants and water vapor.

Refrigerant Charge

Verify Sensor Performance

Verify that thermistor, transducer, and switch inputs are reading
correctly. These values can be accessed through the Scrolling
Marquee display in the Temperatures, Pressures, and Inputs menus.
Some values will depend on configuration choices. Refer to the
Control Set Up Checklist completed for the specific unit
installation and to the configuration tables in Appendix A.

Economizer Operation During Power Failure

Dampers have a spring return. In event of power failure, dampers
will return to fully closed position until power is restored. Do not

manually operate damper motor.

48/50PD

Evacuation

Proper evacuation of the system will remove noncondensables and
ensure a tight, dry system before charging. Evacuate from both
high and low side ports. Never use the system compressor as a
vacuum pump. Refrigerant tubes and indoor coil should be
evacuated to 500 microns. Always break a vacuum with dry
nitrogen. The two possible methods are the deep vacuum method
and the triple evacuation method.

Deep Vacuum Method

The deep vacuum method requires a vacuum pump capable of
pulling a minimum vacuum of 500 microns and a vacuum gauge
capable of accurately measuring this vacuum depth. The deep
vacuum method is the most positive way of assuring a system is
free of air and liquid water. (See Fig. 34.)

5000

4500

4000

3500

3000

2500

MICRONS

2000

1500

1000

500

4

3

0

2

1

MINUTES

Fig. 34 -- Deep Vacuum Graph

Triple Evacuation Method

The triple evacuation method should only be used when vacuum
pump is capable of pumping down to 28--in. of mercury and
system does not contain any liquid water. Proceed as follows:

1. Pump system down to 28--in. of mercury and allow pump
to continue operating for an additional 15 minutes.

2. Close service valves and shut off vacuum pump.

LEAK IN
SYSTEM

VACUUM TIGH
TOO WET

TIGHT
DRY SYSTEM

56

7

C06264

Amount of refrigerant charge is listed on unit nameplate. Refer to
Carrier GTAC II; Module 5; Charging, Recovery, Recycling, and
Reclamation section for charging methods and procedures. Unit
panels must be in place when unit is operating during charging
procedure.

Puron® (R-410A) refrigerant systems should be charged with
liquid refrigerant. Use a commercial type metering device in the
manifold hose.

!

WARNING

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause personal
injury, death and/or equipment damage.

Puron (R--410A) refrigerant systems operate at higher
pressures than standard R-- 22 systems. Do not use R--22
service equipment or components on Puron refrigerant
equipment. Gauge set, hoses, and recovery system must
be designed to handle Puron refrigerant. If unsure
about equipment, consult the equipment manufacturer.

IMPORTANT: Do not use recycled refrigerant as it may contain

contaminants.

No Charge in the System

Use standard evacuating techniques. After evacuating system,
weigh in the specified amount of refrigerant (refer to unit
nameplate). Verify charge using the charging chart via “Charge in
the System.”

Charge in the System

IMPORTANT: The circuit must be running in normal cooling

mode with the compressor capacity at 100%. The VFD must be
running at max fan speed and indoor airflow must be within
specified air quantity limits for cooling (See Appendix D). All
outdoor fans must be on and running at high speed. Use the
Cooling Service Test Outdoor Fan Override function to start all
outdoor fans.

An accurate pressure gauge and temperature--sensing device is
required. Charging is accomplished by ensuring the proper amount
of liquid subcooling. Connect pressure gauge to the compressor
discharge service valve. Connect temperature sensing device to the
liquid line between the condenser and the TXV (thermostatic
expansion valve), and insulate it so that ambient temperature does
not affect reading. Use the cooling charging chart (Fig. 35 -- 36) to
determine if additional charge is needed or if some charge needs to
be removed from the system.

To Use the Cooling Charging Chart

Use the temperature and pressure readings, and find the
intersection point on the cooling charging chart. If intersection
point on chart is above line, add refrigerant. If intersection point on
chart is below line, carefully recover some of the charge. Recheck
suction pressure as charge is adjusted.

64

The TXV is set to maintain between 10 and 15 degrees of

R410AREREFRIRIGE

RANT

OUTDOORFR FANMN M UST BEO PERATING ONHN HIGHSH SPEED

20

40

60

80

100

120

140

160

150

20025250 30000

350

400

450

500

550

600

Co mpresssso r D

isc ha rge P ressssu re, [ p

sig]

Adddd Chaharge if A

bove

the Cururve

RemoveveChCharargeifif Belolow th eCuCurveve

Outdoor

Coil L

eaving

Temp

eratu

re,

[Deg

rees

F]

R410AREREFRIRIGE

RANT

OUTDOORFR FANMN M UST BEO PERATING ONHN HIGHSH SPEED

20

40

60

80

100

120

140

160

150

20025250 30000

350

400

450

500

550

600

Co mpresssso r D

isc ha rge P ressssu re, [ p

sig]

Adddd Chaharge if A

bove

the Cururve

RemoveveChCharargeifif Belolow th eCuCurveve

Outdoor

Coil L

eaving

Temp

eratu

re,

[Deg

rees

F]

superheat at the compressors. The valves are factory set and cannot
be adjusted. Do not use A TXV designed for use with R-- 22.

16

14

F]

12

rees

[Deg
re,

eratu

10

Te m p

eavin

80

Coil

Outdoor

60

40

20

R4

bov

the

150

200

RANT

350

400

450

500

550

isc

sig

600

C07040

Fig. 35 -- Charging Chart ⎯ 48/50PD05

16

14

F]

12

rees

[Deg
re,

eratu

10

Te m p

eavin

80

Coil

Outdoor

60

40

20

R4

bov

the

150

200

RANT

350

400

450

500

550

isc

sig

600

Table 2 6 — Altitude Compensation*

48PG03--07

ELEVATION

(ft)

0-1,999

2,000
3,000
4,000
5,000
6,000
7,000
8,000

9,000
10,000
11,000
12,000
13,000
14,000

*As the height above sea level increases, there is less oxygen per cubic foot of air.

Therefore, heat input rate should be reduced at higher altitudes. Includes a 4% input
reduction per each 1000 ft.

† Orifices available through your Carrier dealer.

NATURAL GAS

ORIFICE†

45 52
47 52
47 53
47 53
48 53
48 53
48 53
49 54
49 54
50 54
51 54
51 55
52 55
52 56

PROPANE

ORIFICE†

Gas V alve Adjustment

The gas valve opens and closes in response to the thermostat or
limit control.

When power is supplied to valve terminals W2 (High Fire) and C1,
the main valve opens to its preset position.

The regular factory setting is stamped on the valve body.
To adjust regulator:

1. Set unit at setting for no call for heat.

2. Turn main gas valve to OFF position.

3. Remove
connection. Install a suitable pressure-measuring device.

4. Set main gas valve to ON position.

5. Set thermostat at setting to call for heat.

6. Remove screw cap covering regulator adjustment screw.
(See Fig. 37.)

7. Turn adjustment screw clockwise to increase pressure or
counterclockwise to decrease pressure. The setting is 3.50
in.wgonsizes03-14and3.00onsize16--28.

8. Once desired pressure is established, set unit setting for no
call for heat, turn off main gas valve, remove
pressure-measuring device, and replace
screw cap.

1

/8-in. pipe plug from manifold pressure tap

1

/8-in. pipe plug and

48/50PD

Fig. 36 -- Charging Chart ⎯ 48/50PD06

PuronR Refrigerant

Puron refrigerant operates at 50 to 70 percent higher pressures than
R-22. Be sure that servicing equipment and replacement
components are designed to operate with Puron refrigerant. Do not
mix with components that have been used with other refrigerants.
Puron refrigerant, as with other HFCs, is only compatible with
POE oils.

Recovery cylinder service pressure rating must be 400 psig. Puron
systems should be charged with liquid refrigerant. Use a
commercial-type metering device in the manifold hose. Manifold
sets should be 750 psig high-side and 200 psig low-side with 520
psig low-side retard. Use hoses with 750 psig service pressure
rating. Leak detectors should be designed to detect HFC
refrigerant.

C07041

C08663

Fig. 37 -- 48PD Gas Valve

65

High Altitude

For high altitude applications greater than 2,000 ft the heat input
rate should be reduced. The higher the altitude is above sea level,
the less oxygen is in the air. See Table 8 for orifice sizing. A high
altitude kit is available to convert unit for altitudes up to 7,000 ft.

Main Burners

For all applications, main burners are factory set and should require
no adjustment.

Main Burner Removal

1. Shut off (field-supplied) manual main gas valve.

2. Shut off power to unit.

3. Open gas section access door.

4. Disconnect gas piping from gas valve inlet.

5. Remove wires from gas valve.

6. Remove wires from rollout switch.

7. Remove sensor wire and ignitor cable from IGC board.

9. Rotate the burner/manifold assembly to the right, away
from the flue extension and lift burner/manifold assembly
out of unit.

Cleaning and Adjustment

1. Remove burner rack from unit as described in Main Burner
Removal section above.

2. Inspect burners, and if dirty, remove burners from rack. The
two outer burners have the flame crossover closed off in
order to prevent gas flow from exiting the sides of the
burner assembly. To prevent ignition problems, make sure
the outer burners are returned to their original position when
done servicing.

3. Using a soft brush, clean burners and crossover port as
required.

4. Adjust spark gap. (See Fig. 38.)

5. Reinstall burners on rack.

6. Reinstall burner rack as described above.

8. Remove 2 screws that hold the burner assembly to vestibule
plate.

48/50PD

E

E

SPARK GAP

0.181”
[4.6]

SECTION

C-C

AA

C

C

SECTION

A-A

SCALE 1:1

B

Fig. 38 -- Spark Gap Adjustment

Filter Drier

Replace filter drier whenever refrigerant system is exposed to
atmosphere. Only use factory specified liquid-line filter driers with
working pressures no less than 650 psig. Do not install a
suction-line filter drier in liquid line. A liquid-line filter drier
designed for use with Puron® refrigerant is required on every unit.

Protective Devices

Compressor Rotation

Overcurrent

Each compressor has internal line break motor protection.

Overtemperature

Each compressor has an internal protector to protect it against
excessively high discharge gas temperatures.

25.4

MAX. TYP.

B

SECTION

E-E

SCALE 2:1

SECTION

SCALE 1:1

D

D

B-B

SPARK GAP

0.120 TO 0.140”
[3.05 TO 3.56]

SECTION

D-D

C06269

High--Pressure Switch

If the high-pressure switch trips, the compressor will shut down
and the current sensor (3-phase units only) will not detect current.
See the Current Sensor section below for more information.

Current Sensor (CS) (3--Phase Units Only)

The purpose of the CS is to detect losses in compressor power.
After detecting a loss in compressor power, unit control locks out
the compressor for 15 minutes. After 15 minutes, the alarm will
automatically reset. If this alarm occurs 3 times consecutively, the
compressor will remain locked out until an alarm reset is initiated
via CCN or manually via the Scrolling Marquee display (see
Alarms and Alerts section for more details).

IMPORTANT: The current sensor is not currently used in the
48/50PD, but reserved for future implementation.

66

Evaporator Fan Motor Protection

Indoor-fan motors less than 5 hp are equipped with internal
overcurrent and overtemperature protection. Protection devices
reset automatically. Disconnect and lock out power when servicing
motor. Indoor-fan motors 5 hp and larger are equipped with a
manual reset, calibrated trip, magnetic circuit breaker and
overcurrent protection. Do not bypass connections or increase the
size of the breaker to correct trouble. Determine the cause and
correct it before resetting the breaker.

Condenser--Fan Motor Protection

Each condenser-fan motor is internally protected against
overtemperature.

Fuses are located in the control box and feed power to the
condenser fan motors. Always replace blown fuses with the
correct size fuse as indicated on the unit fuse label.

Saturated Suction P ressure (SSP)

If the SSP for a particular circuit is reading below the alarm set
point for an extended period of time, that circuit will be shut down.
After 15 minutes, the alarm will automatically reset. If this alarm
occurs 3 times consecutively, the circuit will remain locked out
until an alarm reset is initiated via CCN or manually via the
Scrolling Marquee display (see Alarms and Alerts section for more
details).

Relief Devices

All units have relief devices to protect against damage from
excessive pressures (i.e., fire). These devices protect the high and
low side and are located at the suction line service port. Protect
joint during brazing operations near joint.

Compressor Sound Shield

The 48/50PD units are equipped with a compressor sound shield.
The sound shield has two parts, the compressor jacket encloses the
shell of the compressor and the base shield is installed between the
bottom of the compressor and the unit base pan. The sound shield
reduces the difference in noise levels as the compressor loads and
unloads in the frequency ranges of 200 to 2000 Hz. Since the
human speech occurs in the 200 to 2000 Hz frequency ranges the
sound shield reduces the speech annoyance caused by the loading
and unloading of the compressor.

The compressor jacket is held closed around the compressor by
Velcro tape. To remove the compressor jacket, separate the Velcro
along the side and top of the compressor. Slide the jacket toward
the back of the compressor to remove the jacket. Make sure the
jacket is reinstalled after servicing or replacing the compressor.

The compressor base shield is accessible when the compressor is
removed. To remove the base shield without removing the
compressor, remove one front compressor mounting bolt and
grommet. At the three remaining compressor mounting grommets,
cut the sound shield so that the base shield can be slid in the
direction of the compressor mounting bolt and grommet that was
removed. (See Fig. 39.) Cut replacement base shield along dotted
lines as shown in Fig. 39 and reinstall in reverse direction. When
installing the base shield, place the soft side facing upward.
Reinstall compressor mounting grommet and bolt.

Cut Compressor Base Sound

COMPRESSOR BASE

SHIELD

Remove this compressor
mounting bolt and grommet
at this location.

Slide Compressor Base Sound
Shield in this direction.

C08664

Fig. 39 -- Base Sound Shield

Control Circuit, 24-- V

Each control circuit is protected against overcurrent by a 3.2 amp
circuit breaker. Breaker can be reset. If it trips, determine cause of
trouble before resetting.

Replacement Parts

A complete list of replacement parts may be obtained from any
Carrier distributor upon request.

Diagnostic L EDs

The MBB, ECB, AUX1, IGC and DSC control boards have LED
lights for diagnostic purposes. The meanings and error codes can
be found in the the troubleshooting section of this manual.

48/50PD

67

APPENDIX A - LOCAL DISPLAY AND CCN TABLES

Table 2 7 — MODE - RUN STATUS

ITEM EXPANSION RANGE UNITS

RUN STATUS STATUS DISPLAY

VIEW Auto View of Run Status (VIEW = Display only)

HVAC HVAC Mode Status 1=Disabled

OCC Currently Occupied Ye s/ No OCCUPIED
SAT Supply Air Temperature xxx..x dF SAT_DISP
ALRM Current Alarms & Alerts xx ALRMALRT
TIME Time of Day xx.xx hh.mm TIMECOPY

VERS Software Version Numbers VERSIONS

MBB CESR131459--- xx --- xx ( x x --- x x in

ECB CESR131249---xx--- xx MODEL_NUMBER_02
AUX CESR131333--- xx --- xx MODEL_NUMBER_ 03
MARQ CESR131171---xx--- xx MODEL_NUMBER_04

MODE Control Modes MODEDISP

SYS Unit operation disabled

48/50PD

HVAC HVAC Operation Disabled

HV.DN Remote HVAC Mode Disable Ye s/N o HVACDOWN forcible
EFF.C Cool Setpoint in Effect xxx.x CSP_EFF
EFF.H Heat Setpoint in Effect xxx.x HSP_EFF
OCC Currently Occupied Ye s/ No OCCUPIED forcible
T. O V R Timed Override in Effect Yes /No MODETOVR
LINK Linkage Active Yes/N o MODELINK
D.LMT Demand Limit In Effect Yes / No MODEDMDL
C.LOC Compressor OAT Locko ut Yes/ N o COMPLOCK
H.LOC Heat OAT Lockout Ye s/ No HEATLOCK
E.LOC Econo Cool OAT Lockout Ye s/N o ECONLOCK

COOL Cooling Status COOLDISP

DMD.C Cooling Demand xxx.x ^F COOL_DMD
SA.CP Supply Air Cont rol Point xxx.x dF SA_CTLPT
SASP Cool Supply Air Setpoint xxx.x dF SASP
SR.CD Cool Demand SASP Reset xxx.x ^F CD_RESET
SR.RH De humidifying SASP Reset xxx.x ^F RH_RESET
F.SPD Commanded Fan Speed xxx % FANSPEED
CMP.A Compre ssor A Feedback On/Off COMP_A
TG.A Compressor A Timeguard xxx sec TIMGD_A
CAPC Compressor Capacity xxx % CAPACITY
MAX.C Max Compressor Capacity xxx % MAX_CAPC forcible
MIN.C Min Compressor Capacity xxx % MIN_CAPC
LMT.C Max Capacity In Effect xxx % CAPLIMIT
SST.A Sat . Suctio n Temp A xxx.x dF SST_A
SSP.A Suction Pressure A xxx.x psig SSP_A
SCT.A Sat. Condenser Temp A xxx.x dF SCT_A
SCP.A Condenser Pressure A xxx.x psig SCP_A
OFC.1 Outdoor Fan 1 Relay On/Off OFC_1

HEAT Heating Status HEATDISP

DMD.H Heating Demand xxx.x ^F HEAT_DMD
AVL.H Available Heating Stages x AVLHSTGS
REQ.H Requested Heating Stages x REQHSTGS
MAX.H Max Allowed Heat Stages x MAXHSTGS forcible
LMT.H Max Heat Stage In Effect x HSTGLIMT
F.SPD Commanded Fan Speed xxx % FANSPEED
HT.1 Heat Stage 1 Relay On/Off HEAT_1
TG.H1 Heat Stage 1 Timequard xxx sec TIMGD_H1
HT.2 Heat Stage 2 Relay On/Off HEAT_2
TG.H2 Heat Stage 2 Timequard xxx sec TIMGD_H2

ECON Economizer Status ECONDISP

EC.CP Econo Commanded Position xxx % ECONOCMD
EC.AP Econo Actual Position xxx % ECONOPOS
EC.MP MinPositioninEffect xxx % MIN_ POS
IAQ.S IAQ Level (switch) High/Low IAQIN
IAQ IAQ Level (sensor) xxxx ppm IAQ
OAT Outdoor Air Temperature xxx.x dF OA_TEMP
ENTH Outdoor Enthalpy Switch High/Low ENTHALPY
OAQ OAQ Level (sensor) xxxx ppm OAQ
PE.1 Power Exhaust 1 Relay On/Off PE_1
PE.2 Power Exhaust 2 Relay On/Off PE_2

HRS Component Run Hours STRTH OUR

A1 Compressor A1 Run Hours xxxxx.xx hours HR_A1 forcible
CCH Crankcase Htr Run Hours xxxxx.xx hours HR_CCH forcible
IDF Indoor Fan Run Hours xxxxx.xx hours HR_IDF forcible
OFC.1 Outdoor Fan 1 Run Hours xxxxx.xx hours HR_OFC_1 forcible
HT.1 Heat Stage 1 Run Hours xxxxx.xx hours HR_HTR_1 forcible
HT.2 Heat Stage 2 Run Hours xxxxx.xx hours HR_HTR_2 forcible
PE.1 Power Exhaust1 Run Hours xxxxx.xx ho urs HR_PE_1 forcible
PE.2 Power Exhaust2 Run Hours xxxxx.xx ho urs HR_PE_2 forcible
ALRM Alarm Relay Run Hours xxxxx.xx hours HR_ALM forcible

Unit operation enabled
Service test enabled

Ventilation (fan--- only)
Cooling
Unoccupied Free Cooling
Heating

2=Fan Only
3=Cool
4=Heat

table)

CCN

TABL E/ SUB ---TABLE

CCN POINT

HVACMODE

MODEL_NUMBER_01

SYS_MODE_TEXT1
SYS_MODE_TEXT2
(table only)
SYS_MODE_TEXT3
(table only)
HVACMODE_TEXT_1
HVACMODE_TEXT_2
(table only)
HVACMODE_TEXT_3
(table only)

CCN WRITE

STATUS

68

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 27 — MODE - RUN STATUS (cont)

ITEM EXPANSION RANGE UNITS

STRT Component Starts

A1 Compressor A1 Starts xxxxxx ST_A1 forcible
CCH Crankcase Heater Starts xxxxxx ST_CCH forcible
IDF Indoor Fan Starts xxxxxx ST_IDF forcible
OFC.1 Outdoor Fan 1 Starts xxxxxx ST_OFC_1 forcible
HT.1 Heat Stage 1 Starts xxxxxx ST_HTR_1 forcible
HT.2 Heat Stage 2 Starts xxxxxx ST_HTR_2 forcible
PE.1 Power Exhaust 1 Start s xxxxxx ST_ PE_1 forcible
PE.2 Power Exhaust 2 Start s xxxxxx ST_ PE_2 forcible
ALRM Alarm Relay Starts xxxxxx ST_ALM forcible

(ALRMDISP) = CCN

only)

(GENERIC = CCN

only)

(LON_DATA = CCN

only)

Active Alarm 1 Code xxx ALMCODE1
Active Alarm 2 Code xxx ALMCODE2
Active Alarm 3 Code xxx ALMCODE3
Active Alarm 4 Code xxx ALMCODE4
Active Alarm 5 Code xxx ALMCODE5
Reset All Current Alarms Ye s /No ALRESET forcible
Reset Alarm H istory Yes/ No ALHISCLR forcible

nviSpaceTemp xxx.x dF NVI_SPT forcible
nviSetPoint xxx.x dF NVI_SP forcible
nvoSpaceTemp xxx.x dF NVO_ SPT
nvoUnitStatus.mode xxxx NVO_MODE
nvoUnitStatus.heat_out_p xxx.x % NVO_HPRI
nvoUnitStatus.heat_out_s xxx.x % NVO_HSEC
nvoUnitStatus.cool_out xxx.x % NVO_COOL
nvoUnitStatus.econ_out xxx.x % NVO_ECON
nvoUnitStatus.fan_out xxx % NVO_ FAN
nvoUnitStatus.in_alarm xxx NVO_ALRM
nviSetPtOffset xxx.x ^F NVI_SPTO forcible
nviOutside Temp xxx.x dF NVI_OAT forcible
nviOutside RH xxxx.x % NVI_OARH forcible
nvoEffectSetPt xxx.x dF NVO_EFSP
nvoOutsideTemp xxxx.x dF NVO_OAT
nvoOutsideRH xxx.x % NVO_OARH
nviSpaceRH xxx.x % NVI_SPRH forcible
nviCO2 xxxxx NVI_CO2 forcible
nvoCO2 xxxxx NVO_ CO2
nvoTEMP1 xxx.x dF NVO_SAT
nvoTEMP2 xxx.x dF NVO_RAT
nviPCT1 xxx.x % NVI_ RHSP forcible
nvoPCT1 xxx.x % NVO_SPRH
nviDISCRETE1 Off/On NVI_FSD forcible
nviDISCRETE2 No/Yes NVI_OCC forcible
nviDISCRETE3 Off/On NVI_IAQD forcible
nvoDISCRETE1 Off/On NVO_ FSD
nvoDISCRETE2 No /Yes NVO_OCC
nvoDISCRETE3 Off/On NVO_IAQD
nciCO2Limit xxxxx NCI_CO2 forcible
nciSetPnts.occupied_cool xxx.x dF NCI_OC SP forcible
nciSetPnts.standby_cool xxx.x dF NCI_SCSP forcible
nciSetPnts.unoccupd_co ol xxx.x dF NCI_UCSP forcible
nciSetPnts.occupied_heat xxx.x dF NCI_OHSP forcible
nciSetPnts.standby_heat xxx.x dF NCI_SHSP forcible
nciSetPnts.unoccupd_heat xxx.x dF NCI_UHSP forcible

CCN

TABL E/ SUB ---TABLE

ALRMDISP

GENERIC

LON_ DATA

CCN POINT

up to 20 points

CCN WRITE

STATUS

48/50PD

69

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 28 — MODE - SERVICE TEST

ITEM EXPANSION RANGE UNITS DEFAULT CCN TABLE/SUB--- TA BL E CCN POINT

SERVICE TEST MAINTENANCE DISPLAY

TEST Field Service Test Mode On/Off Off (TEST = display only) MAN_CTRL forcible forcible
INDP Test Independent Outputs TESTINDP

ECON Economizer Position Test 0 to 100 % 0 S_ ECONO forcible forcible
E.CAL Calibrate Economizer On/Off Off S_ ECOCAL forcible forcible
PE.1 Power Ex haust 1 Test On/Off Off S_PE_1 forcible forcible
PE.2 Power Ex haust 2 Test On/Off Off S_PE_2 forcible forcible
ALRM Alarm Relay Test On/Off Off S_ ALMOUT forcible forcible
CCH Crankcase Heat Test On/Off Off S_CCH forcible forcible

FANS Tes t Fa n s TESTFANS

IDF Supply VFD Power Test On/Off Off S_IDF forcible forcible
F.SPD Indoor Fan Speed Test 0 to 100 % 0 S_VSPEED forcible forcible
OFC.1 Outdoor Fan Relay Test On/Off Off S_OFC_1 forcible forcible

COOL Test Cooling TESTCOOL

CTLR DigScrollCtrlPwrTest On/Off Off S_CMPCTL forcible forcible
CAPC Compressor Capacity Test 0 to 100 % 0 S_VCAP forcible forcible
F.SPD Cool Test Fan Speed 0 to 100 % 0 S_ VSPDCL forcible forcible

48/50PD

HEAT Te st H e a t i n g TESTHEAT

HT.1 Heat Stage 1 Test On/Off Off S_HEAT_1 forcible forcible
HT.2 Heat Stage 2 Test On/Off Off S_HEAT_2 forcible forcible

CCN

WRITE

STATUS

Table 29 — MODE - TEMPERATURES

ITEM EXPANSION RANGE UNITS CCN TABLE /S UB --- TA BL E CCN POINT

STATUS DISPLAY

TEMPERATURES UINPUT

AIR.T Air Temperatures

SAT Supply Air Temperature xxx.x dF SAT_DISP
OAT Outdoor Air Temperature xxx.x dF OA_TEMP forcible forcible
SPT Space Temperature xxx.x dF SPACE_T forcible forcible
SPTO Space Temperature Offset xxx.x dF SPTO forcible forcible
RAT Return Air Temperature xxx.x dF RETURN_T forcible forcible

REF.T Refrigerant Temperatures xxx.x dF

SST.A Sat. Suction Temp A xxx.x dF SST_A
SCT.A Sat. Condenser Temp A xxx.x dF SCT_A

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

DISPLAY

WRITE

STATUS

Table 30 — MODE - PRESSURES

ITEM EXPANSION RANGE UNITS CC N TABLE/ SUB--- TA BLE CCN POINT

STATUS DISPLAY

PRESSURES UINPUT

SSP.A Suction Pressure A xxx.x psig SSP_A
SCP.A Condenser Pressure A xxx.x psig SCP_A

CCN

WRITE

STATUS

70

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 31 — MODE - SET POINTS

ITEM EXPANSION RANGE UNITS DEFAULT CCN TAB LE /SUB ---TABLE CCN POINT

SETPOINTS SET_PNT

OCSP Occupied Cool Setpoint 55 to 80F dF 78 OCSP
UCSP Unoccupied Cool Setpoint 75 to 95F dF 85 UCSP
OHSP Occupied Heat Setpoint 55 to 80F dF 68 OHSP
UHSP Unoccupied Heat Setpoint 40 to 80F dF 60 UHSP
GAP Heat --- Cool Setpoint Gap 2 to 10F ^F 5 HCSP_GAP
STO.R SPT Offset Range (+/ --- ) 0to5F ^F 5 SPTO_RNG
SASP Cool Supply Air Setpoint 45 to 75 dF 65 SASP
RH.SP Space RH Setpoint 30 to 95 % 50 SPRH_SP
RH.DB Space RH Deadband 2to20 % 5 SPRH_DB
C.LO Compressor Lockout Temp 0 to 100F dF 0 OATLCOMP
HT.LO Heating Lockout Temp 40 to 125F dF 75 OATLHEAT
EH.LO Econo Cool Hi Temp Limit 40 to 100F dF 65 OATLECLH
EL.LO Econo Cool Lo Temp Limit --- 30 to 50F dF 0 OATLECLL
FC.LO Free Cool Low Temp Limit 0 to 70F dF 50 OATLUEFC

Table 3 2 — MODE - - I N P U T S

ITEM EXPANSION RANGE UNITS CCN TA BL E/ SUB --- TABLE

STATUS DISPLAY

INPUTS UINPUTS

GEN.I General Inputs

FIL.S Filt er Status Switch Dirty/Clean FILTSTAT forcible
FAN. S Fan Status Switch On/Off FAN_STAT forcible
FDWN Fire Shutdow n Switch On/Off FIREDOWN forcible
ENTH Outdoor Enthalpy Switch High/Low ENTHALPY forcible
RM.OC Remote Occupancy Switch On/Off REM_OCC forcible
HUM Space Humidity Switch High/Low HUM_STAT forcible
CMP.A Compressor A Feedback On/Off COMP_A
C.ALM Scroll Compressor Alarm On/Off COMP_ALM

CS.IN Current Sensor Inputs

CS.A1 Compressor A1 Feedback On/Off CS_A1

AIR.Q Air Quality Inputs

IAQ.S IAQ Level (switch) High/Low IAQIN forcible forcible
IAQ IAQ Level (sensor) xxxx ppm IAQ forcible forcible
OAQ OAQ Level (sensor) xxxx ppm OAQ forcible forcible
SP.RH Space Humidity Sensor xxx.x % SPRH forcible forcible

SETPOINT CONFIGURATION

CCN

POINT

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

48/50PD

71

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 33 — MODE - OUTPUTS

ITEM EXPANSION RANGE UNITS CCN TABLE /S UB --- TA BL E CCN POINT

OUTPUTS UOUTPUT

FANS Fan Outp uts

IDF Indoor Fan VFD Pwr Relay On/Off IDF
F.SPD Commanded Fan Speed xxx % FANSPEED
OFC.1 Outdoor Fan 1 Relay On/Off OFC_1

COOL Cool Outputs

CTLR DigitalScrollCtrlPwr On/Off COMPCTLR
CAPC Compressor Capacity xxx % CAPACITY
CCH Crankcase Heat Relay On/Off CCH

HEAT Heat Outputs

HT.1 Heat Stage 1 Relay On/Off HEAT_1
HT.2 Heat Stage 2 Relay On/Off HEAT_2

ECON Economizer Outputs

EC.CP Econo Commanded Position 0 to 100 % ECONOCMD forcible forcible
EC.AP Econo Actual Position 0 to 100 % ECONOPOS
PE.1 Power Exhaust 1 Relay On/Off PE_1 forcible forcible

48/50PD

PE.2 Power Exhaust 2 Relay On/Off PE_2 forcible forcible

ALRM Alarm Relay On/Off ALMOUT forcible forcible

STATUS DISPLAY

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

72

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 34 — MODE - CONFIGURATION

ITEM EXPANSION RA NGE UNITS DEFAULT

CONFIGURATION SERVICE

DISP Display Configuration DISPLAY

METR Met ric Display On/Off Off DISPUNIT 11
LANG Language Select ion 0=English

PROT Password Enable Enable/Disable Disable PA SS_ EBL 12
PSWD Service Password 0000 to 9999 1111 PA SSW OR D 12
TEST Test Display LEDs On/Off Off (display only, not in

UNIT Unit Configuration UNIT

S.DLY Startup Delay 0 to 600 sec 30 STARTDLY 12
OC.FN FanOnWhenOccupied Ye s/N o Ye s OCC_FAN 12
IDF.F Shut Down on IDF Failure Ye s /No Ye s FATALFAN 12
FS.MX Supply Fan Maximum

FS.MN Supply Fan Minimum

FS.VM Vent Mode Fan Speed 40 to 100 ^F 50 SPEEDVNT 12
FN.SW Fan Status Switch 0=No Switch

FL.SW Filter St atus Switch 0=No Switch

FS.SW Fire Shutdown Sw itch 0=No Switch

RM.SW Remote Occupancy

RH.S RH Sensor on OAQ Input Ye s /No No RH_OAQ 13
RH.SW Space Humidity Switch 0=No Switch

TCS.C Temp Cmp Strt Cool Factr 0to60 mins 0 TCSTCOOL 13
TCS.H TempCmpStrtHeatFactr 0to60 mins 0 TCSTHEAT 13

COOL Cooling Configuration COOL_CFG

MIN.C Min Compressor Capacity 15 to 80 % 70 MIN_CAPC 14
FS.CD Fan Speed Control

MRT.C Compressor Min On Time 120 to 999 sec 180 MIN_ON
MOT.C Compressor Min Off Time 300 to 999 sec 300 MIN_OF F
RST.C Runtime to Reset Strikes 120 to 999 sec 300 MIN_ON_S 24
FOD.C Fan-off Delay, Mech Cool 0 to 600 sec 60 COOL_FOD
CS.A1 Current Sensing A1 Enable/Disable Disable: reserved for

C.LO Compressor Lockout

ALM.N Alert Each Strike Yes//No Yes ALM_NOW 24
SAT Supply Air Temperature

SASP Cool Supply Air Setpoint 45 to 75 dF 65 SASP 17
SA.MU SASP Maximum Reset Up 0to20 ^F 10 SASPMAXU 18
SA.MD SASP Maximum Reset

SAT.U Minimum SAT Upper Level 35.0 to 65.0 dF 60 SATMIN_H
SAT.L Minimum SAT Lower Level 35.0 to 65.0 dF 45 SATMIN_L

SST Low Suction Control

SST.O Suction OK Temperature 10 to 50 dF 18 SSTOK 26
SST.1 Low Suct ion --- Level 1 10 to 50 dF 20 SSTLEV1 26
SST.2 Low Suct ion --- Level 2 5to50 dF 15 SSTLEV2 26
SST.3 Low Suct ion --- Level 3 0to50 dF 10 SSTLEV3 26
PSI.D Ckt A Minimum Pressure 0 to 500 psig 20 DELTAP_A 26

OFC Outdoor Fan Control

1.MXP Fan Lev1 Max Pressure 100 to 500 psig 450 LEV1MAXP 15

2.MNP Fan Lev2 Min Pressure 100 to 500 psig 200 LEV2MINP 15

2.ON FanLev2OnTemperature 0 to 100 F 55 LEV2ON 15

2.OFF Fan Lev2 Off Temperature 0 to 100 F 45 LEV2OFF 15

Speed

Speed

Switch

Demand

Te m p

Down

1=Spanish
2=French
3=Portuguese

80 to 100 % 100 SPEEDMAX 12

10 to 40 % 20 SPEEDMIN 12

1=Normal Open
2=Normal Closed

1=Normal Open
2=Normal Closed

1=Normal Open
2=Normal Closed
0=No Switch
1=Normal Open
2=Normal Closed

1=Normal Open
2=Normal Closed

1to9.9 ^F 3 SPEEDDMD 17

0 to 100F dF 0 OATLCOMP

--- 2 0 t o 0 ^F --- 1 0 SASPMAXD 18

0 LANGUAGE 11

0: no FIOP
1: FIOP

0: no FIOP
1: FIOP

0: no FIOP
1: FIOP

0 REMOCCFG 12

0 HUMSTCFG 13

future use
DO NOT ENABLE

CCN

TABL E/ SUB ---TABLE

CONFIGURATION

table)

CCN POINT

DISPTEST 12

FANSTCFG 12

FILSTCFG 12

SHTDNCFG 12

A1_SENSE 25

PAG E

NO.

48/50PD

73

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 34 — MODE - CONFIGURATION (cont)

ITEM EXPANSION RA NGE UNITS DEFAULT

HEAT Heating Configuration HEAT_CFG

HT.TY Type of Heat Installed 0=No Heat

N.HTR Number of Heat Stages 1to2 1 (50 series <15kW)

MRT.H Heat Minimum On Time 60 to 999 sec 120 HMIN_ON 22
MOT.H Heat Minimum Off Time 60 to 999 sec 120 HMIN_OFF 22
H.DEC Heat Stage Decrease

H.INC Heat Stage Increase Time 120 to 999 sec 450 HSTAGINC 21
FOD.E Fan--- off Delay, Elect Heat 10 to 600 sec 30 ELEC_FOD 22
FOD.G Fan--- off Delay, Gas Heat 45 to 600 sec 45 GAS_FOD 20
HT.LO Heating Lockout Temp 40 to 125F dF 75 OATLHEAT 20
SAT SUPPLY AIR

SAT.H SAT Heat Mode Sensing Enable/Disable Disable SAT_HEAT 21

48/50PD

ECON Economizer Configuration ECON_CFG

SAM.L Maximum SAT Lower

SAM.U Maximum SAT Upper

SPT SPACE TEMPERATURE

HT.PD SPT Heat Demand (+)

HT.ND SPT Heat Demand (--- )

H.LAG Heat Thermal Lag Factor 0to5 min 1 HEAT_LAG 21

EC.EN Economizer Installed Ye s /No No: no FIOP

E.CTL Economizer Control Type 1=Dig/Position

MP.25 Econ Min at 25%

MP.50 Econ Min at 50%

MP.75 Econ Min at 75%

MP.MX Econ Min at Max

EC.MX Econo Cool Max Position 0 to 100 % 100 ECONOMAX
M.ANG Min Actuator Ctrl Angle 75 to 90 88 MINANGLE 27
EH.LO Econo Cool Hi Temp Limit 40 to 100F dF 65 OATLECLH 15
EL.LO Econo Cool Lo Temp Limit --- 30 to 50F dF 0 OATLECLL 15
DF.DB Diff Dry Bulb Control Disable/Enable Enable DIFFBULB
UEFC Unoccupied Free Cooling 0=Disabled

FC.TM Free Cool PreOcc Time 1 to 9999 min 120 UEFCTIME 16
FC.LO Free Cool Low Temp Limit --- 30 to 70F dF 50 OATLUEFC 16
PE.EN Power Exha ust Installed Ye s /No No: no FIOP

PE1.C Power Exhaust Stage1

PE2.C Power Exhaust Stage2

IDF.C Indoor Fan Max Speed

EN.SW Enthalpy Switch 0=No Switch

Time

TEMPERATURE

Level

Level

Level

Level

Fanspeed

Fanspeed

Fanspeed

Fanspeed

CFM

CFM

CFM

1=Gas
2=Electric

120 to 999 sec 300 HSTAGDEC 22

85 to 200 dF 140 SATMAX_L 21

85 to 200 dF 160 SATMAX_H 21

0.5 to 5 ^F 1 HDEM_POS 21

--- 5 t o --- 0 . 5 ^F --- 1 HDEM_NEG 21

2=Dig/Command
3=Analog Ctrl
0 to 100 % 0 MINP_25 19

0 to 100 % 0 MINP_50 19

0 to 100 % 0 MINP_75 19

0 to 100 % 30 MINP_MAX 19

1=Unoccupied
2=Preoccupancy

100 to 15000 cfm 600 PE1_CFM 16

100 to 15000 cfm 0 PE2_CFM 16

500 to 15000 cfm 1600 (05)

1=Normal Open
2=Normal Closed

0(50serieswithno
electric heat)
1(48series)
2(50serieswith
electric heat)

2(48series,50
series >=15kW)

Yes : F IOP
1 ECON_CTL 10

2 UEFC_CFG 15

Yes : F IOP

2000 (06)
0: no FIOP

1: FIOP

CCN

TABL E/ SUB ---TABLE

CCN POINT

HEATTYPE 20

NUM_HEAT 22

ECONO 8

PE_ENABL 16

IDF_CFM 16

ENTHLCFG 59

PAG E

NO.

74

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 34 — MODE - CONFIGURATION (cont)

ITEM EXPANSION RA NGE UNITS DEFAULT

AIR.Q Air Quality Config. IAQ_CFG

IA.CF IAQ Analog Input Config 0=No IAQ

IA.FN IAQ Analog Fan Config 0=Never

II.CF IAQ Sw itch Input Config 0=No IAQ

II.FN IAQ Switch Fan Config 0=Never

AQ.MN Econo Min IAQ Position 0 to 100 % 10 IAQMINP 17
OVR.P IAQ Override Position 0 to 100 % 100 IAQOVPOS 17
OA.CF OAQ Analog Input Config 0=No OAQ

OAQ.L OAQ Lockout Limit 0 to 5000 600 OAQLOCK 17
AQD.L AQ Differential Low 0 to 5000 100 DAQ_LOW 19
AQD.H AQ Differential High 0 to 5000 700 DAQ_HIGH 19
DF.ON FanOnAQDifferential 0 to 5000 600 DAQFNON 17
DF.OF Fan Off AQ Differential 0 to 5000 200 DAQFNOFF 17
I.4M IAQ Sensor Value at 4mA 0 to 5000 0 IAQ_4MA 16
I.20M IAQ Sensor Value at 20mA 0 to 5000 2000 IAQ_20MA 16
O.4M OAQ Sensor Value at 4mA 0 to 5000 0 OAQ_4MA 17
O.20M OAQ Sensor Value at

H.4M RH Sensor Value at 4mA 0to50 % 0 RH_4MA
H.20M RH Sensor Value at 20mA 60 to 100 % 100 RH_20MA

ALM.O Alarm Relay Config. ALM_CFG

A.SPC SPT/SPRH Sensor Failure Ye s/N o Yes SPACE_AL
A.SRT SAT/RAT Sensor Failure Yes/ No Ye s SATRATAL
A.OAT OAT Thermistor Failure Ye s /N o Ye s OAT_AL
A.CS Current Sensor Failure Ye s /No No CS_AL
A.CMP Compressor Failure Ye s/N o Ye s COMP_AL
A.CKT Refrig Circuit Failure Ye s /N o Ye s CKT_AL
A.SSP SSP Transducer Failure Yes/N o Ye s SSP_AL
A.SCT SCT Thermistor Failure Ye s /No Ye s SCT_AL
A.FAN Indoor Fan Failure Ye s/N o Yes FAN_AL
A.FIL Dirty Filter Yes / No Ye s FILT_AL
A.ECO Economizer Failure Ye s /No Ye s ECON_AL

PID PID Configurations PID_CFG

EC.P Economizer PID --- kP 0.0 to 99.9 2.5 ECONO_P
EC.I Economizer PID --- kI 0.0 to 99.9 0.1 ECONO_I
EC.D Economizer PID --- kD 0.0 to 99.9 1 ECONO_D
EC.DT Economizer PID --- rate 10.0 to 180.0 sec 15 ECONO_DT
E.DBD Economizer PID

CP.P C a p a c i t y P I D --- k P 0 to 99.9 1.5 VCAP_P
CP.I C a p a c i t y P I D --- k I 0 to 99.9 0.1 VCAP_I
CP.D C a p a c i t y P I D --- k D 0 to 99.9 1 VCAP_D
CP.DT Capacity PID --- rate 1to30 secs 5 VCAP_ DT
LK.P Linkage Staging PID --- kP 0.0 to 99.9 10 LINK_P
LK.I Linka ge Sta ging PID --- kI 0.0 to 99.9 5 LINK_I
LK.D Linkage Staging PID --- kD 0.0 to 99.9 5 LINK_D
LK.DT Linkage Staging PID ---

20mA

Deadband

rate

1=DCV
2=Override IAQ
3=Ctrl Min Pos

1=Occupied
2=Always

1=DCV N/O
2=DCV N/C
3=Override N/O
4=Override N/C

1=Occupied
2=Always

1=DCV
2=Lockout OAQ

0 to 5000 2000 OAQ_20MA 17

0to25 % 3 ECONBAND

10.0 to 180.0 secs 30 LINK_DT

0: no FIOP
1: FIOP

0 IAQANFAN 14

0 IAQINCFG 17

0 IAQINFAN 17

0 OAQANCFG 17

CCN

TABL E/ SUB ---TABLE

CCN POINT

IAQANCFG 59

PAG E

NO.

48/50PD

75

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 34 — MODE - CONFIGURATION (cont)

ITEM EXPANSION RA NGE UNITS DEFAULT

(GENERIC = CCN only) GENERICS 5

48/50PD

TRIM Sensor Calibration (CCN TRIM --- see

SPT.C Space Temp Calibration --- 30 to 130 dF 38
SPT.T Space Temp Trim --- 30 to 30 ^F 0 38
SAT.C Supply Air Temp Calib. --- 30 to 130 dF 38
SAT.T Supply Air Temp Trim --- 30 to 30 ^F 0 38
RAT.C Return Air Temp Calib. ---30 to 130 dF 38
RAT.T Return Air Temp Trim --- 30 to 30 ^F 0 37

CCN CCN Configuration 48_50_PD

CCN.A CCN Element Number 1 to 239 1 CCNADD 8
CCN.B CCN Bus Number 0 to 239 0 CCNBUS 8
BAUD CCN Baud Rate 2400, 4800, 9600,

BROD CCN Broadcast Config. BRODEFS

B.TIM CCN Time/Date Broadcast Ye s /N o No CCNBC 23
B.OAT CCN OAT Broadcast Yes / No No OATBC 23
B.GS Global Schedule Broadcst Yes/ N o No GSBC 23
B.ACK CCN Broadcast Ack’er Ye s /No No CCNBCACK 23

SCH.O CCN Schedule Overrides SCHEDOVR

SCH.N Schedule Number 0=Always

HOL.G Accept Global Holidays Yes/N o No HOLIDAYT 23
OV.TL Override Time Limit 0to4 ho urs 4 OTL 23
OV.EX Timed Override Hours 0to4 hours 0 OVR_EXT 23
OV.SP SPT Override Enabled Ye s/ N o Yes TIMEOVER 23

LDSH CCN Schedule Overrides LO AD SHED

S.GRP Loadshed Group Number 0to16 0 SHED_NUM 24
R.MXC Redline Max Capacity 0 to 100 % 100 MAXCREDL 24
S.MXC Loadshed Max Capacity 0 to 100 % 100 MAXCSHED
R.MXH Redline Max Heat Stages 0to2 2 MAXHREDL 24
S.MXH Loadshed Max Heat

POINT 01 Definition 8 --- c h a r A S C I I Poi nt_ 01

POINT 02 Definition 8 --- c h a r A S C I I Poi nt_ 02

POINT 03 Definition 8 --- c h a r A S C I I Poi nt_ 03

POINT 04 Definition 8 --- c h a r A S C I I Poi nt_ 04

POINT 05 Definition 8 --- c h a r A S C I I Poi nt_ 05

POINT 06 Definition 8 --- c h a r A S C I I Poi nt_ 06

POINT 07 Definition 8 --- c h a r A S C I I Poi nt_ 07

POINT 08 Definition 8 --- c h a r A S C I I Poi nt_ 08

POINT 09 Definition 8 --- c h a r A S C I I Poi nt_ 09

POINT 10 Definition 8 --- c h a r A S C I I Poi nt_ 10

POINT 11 Definition 8 --- c h a r A S C I I Poi nt_ 11

POINT 12 Definition 8 --- c h a r A S C I I Poi nt_ 12

POINT 13 Definition 8 --- c h a r A S C I I Poi nt_ 13

POINT 14 Definition 8 --- c h a r A S C I I Poi nt_ 14

POINT 15 Definition 8 --- c h a r A S C I I Poi nt_ 15

POINT 16 Definition 8 --- c h a r A S C I I Poi nt_ 16

POINT 17 Definition 8 --- c h a r A S C I I Poi nt_ 17

POINT 18 Definition 8 --- c h a r A S C I I Poi nt_ 18

POINT 19 Definition 8 --- c h a r A S C I I Poi nt_ 19

POINT 20 Definition 8 --- c h a r A S C I I Poi nt_ 20

3 CCNBAUDD 8

0 SCHEDNUM 23

Stages

19200, 38400

Occupied

1 --- 6 4 =

Local Schedule

=GlobalSchedule

0to2 2 MAXHSHED

65--- 99

CCN

TABL E/ SUB ---TABLE

Maintenance
Display)

CONFIGURATION

CCN POINT

PAG E

NO.

76

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 35 — MODE - TIME CLOCK

ITEM EXPANSION RANGE UNITS DEFAULT

TIME CLOCK CONFIGURATION

TIME Time of Day TIME

TIME Hour and Minute xx.xx hh.mm TIME

DATE Current Date

MNTH Month of Year January, February,  &,

DOM Day of Month 1to31 DOM
YEAR Ye a r xxxx YOCDISP
DAY Day of Week Monda y, Tuesday,  &,

DST Daylight Savings Config. BRODEFS

December

Sunday

CCN

TABL E/ SUB ---TABLE

(continued)

CCN POINT

MOY

DOWDISP

STR.M Start Month January, February,  &,

STR.W Start Week 1to5 2 STARTW
STR.D Start Day 1to7 7 STARTD
M.ADD Minute s to Add 0to90 60 MINADD

STP.M Stop Month January, February,  &,

STP.W Stop Week 1to5 1 STOPW
STP.D Sto p Day 1to7 7 STOPD
M.SUB Minutes to Subtract 0to90 60 MINSUB

SCH.L Occupancy Schedule (SCH.L = Display only)

PER.x Occupancy Period x
OCC.x Occupied From 00.00 to 23.59 hh.mm 00.00 PERxOCC
UNC.x Occupied To 00.00 to 23.60 hh.mm 00.00 PERxUNC
MON.x Monday in Period Ye s/ N o No PERxMON
TUE.x Tuesday in Period Ye s /No No PERxTUE
WED.x Wednesday in Period Yes / No No PERxWED
THU.x Thursday in Period Ye s /No No PERxTHU
FRI.x Friday in Period Yes/ No No PERxFRI
SAT.x Saturday in Period Yes /No No PERxSAT
SUN.x Sunday in Period Ye s /No No PERxSUN
HOL.x Holiday in Period Yes/ N o No PERxHOL
(repeat up to x=8

Periods)

(OCCFECS = CCN only) OCCDEFCS

HOL.L Holiday Schedule HOLIDAY

HOL.x Holiday x 0 HOLDYxxS
MON.x Holiday Start Month 1to12=Januaryto

DAY.x Holiday Start Day 1to31 0 HOLDAYxx
LEN.x Holiday Duration (days) 1to99 0 HOLLENxx
(repeat up to x=9

Holidays)

Timed Override Hours x hours O V R --- E X T
Peri od x DOW

(MTWTFSSH)
Occupied From 00.00 to 24.00 hh.mm 00.00 OCCTODx
Occupied To 00.00 to 24.00 hh.mm 00.00 UNOCTODx

December

December

xxxxxxxx 00000000 DOWx

December

3 STARTM

11 STOPM

0 HOLMONxx

(repeat up to
x=8 Periods)

(repeat up to
xx=30
Holidays)

48/50PD

Table 36 — CCN ONLY TABLES

ITEM EXPANSION RANGE UNITS DEFAULT

(ALARMDEF = CCN only) ALARMDEF

Alarm Routing Control 00000000 to 11111111 11000000 ALRM_CNT
Equipment Priority 0to7 4 EQP_TYPE
Comm Failure Retry Time 1 to 240 min 10 RETRY_TM
R e --- A l a r m T i m e 1 to 255 min 180 RE--- ALARM
AlarmSystemName up to 8 alphanum 48_50_PD ALRM_NAM

(CTLRID = CCN only) C T L R --- I D

Device Name: 48_50_PD
Description: text string
Location: text string
Software Part Number: CESR131459---XX--- XX
Model Number:
Serial Number:
Reference Number:

CCN

TABL E/ SUB ---TABLE

77

CCN POINT

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 37 — MODE - OPERATING MODES

ITEM EXPANSION RA NGE UNITS

OPERATING MODES MAINTENANCE

MODE Cont rol Modes MODES

SYS Unit operation disabled

HVAC HVAC Operation Disabled

HV.DN Remote HVAC Mode

EFF.C Cool Setpoint in Effect xxx.x CSP_EFF
EFF.H Heat Setpoint in Effect xxx.x HSP_EFF
OCC Currently Occupied Yes / No OCCUPIED forcible forcible

48/50PD

T. O V R Timed Override in Effect Yes/ No MODETOVR
LINK Linkage Active Yes /N o MODELINK
D.LMT Demand Limit In Effect Ye s/ N o MODEDMDL
C.LOC Compresso r OAT Lockout Ye s /N o COMPLOCK
H.LOC Heat OAT Lockout Ye s/ N o HEATLOCK
E.LOC Econo Cool OAT Lockout Yes/ No ECONLOCK

COOL Cool Mode Diagnostic COOLDIAG

COOL In Cooling Mode? Yes/ No IN_COOL
OK.CL OK to Select Cool Mode? Ye s/ N o OKTOCOOL
MS.TG Mode Select Timeguard xxx secs COOLMSTG
OK.EC OK to Use Economizer? Yes /No ECONCOOL
OK.MC OK to Use Compressor? Ye s/N o MECHCOOL
C.LOC Compresso r OAT Lockout Ye s /N o COMPLOCK
C.LO Compressor Lockout Temp xxx dF OATLCOMP
IDF Indoor Fan State On/Off IDFSTATE
F.SPD Commanded Fan Speed xxx FANSPEED
REQ.C Requested Cooling

MIN.C Min Compressor Capacity xxx % MIN_CAPC
MAX.C Max Compressor Capacity xxx % MAX_CAPC
LMT.C Max Capacity In Effect xxx % CAPLIMIT
CAPC Compressor Capacity xxx % CAPACITY
CTLR DigitalScrollCtrlPwr On/Off COMPCTLR
CMP.A Compressor A Feedback On/Off COMP_A
ST.A Circuit A Strikes x ASTRIKES
F. L E V Outdoor Fan Level x FANLEV
SAT Supply Air Temperature

SAT Supply Air Temperature xxx.x dF SAT_DISP
SA.DM Supply Air Temp Demand xxx.x ^F SAT_DMD
SAT.U Minimum SAT Upper Level xx.x dF SATMIN_H
SAT.L Minimum SAT Lower Level xx.x dF SATMIN_L

SPT Space Temperature

SPT Space Temperature xxx.x dF SPACE_T forcible
TRND Spacetemp Trend (F/min) xxx.x SPTTREND
DMD.C Cooling Demand xxx.x ^F COOL_DMD

Unit operation enabled
Service test enabled

Ventilation (fan--- only)
Cooling
Unoccupied Free Cooling
Heating

Disable

Capacity

Yes / No HVACDOWN forcible

xxx % REQ_CAPC

CCN

TABL E/ SUB ---TABLE

DISPLAY

CCN POINT

SYS_MODE_TEXT1
SYS_MODE_TEXT2
(table only)
SYS_MODE_TEXT3
(table only)

HVACMODE_TEXT
_1
HVACMODE_TEXT
_2 (table only)
HVACMODE_TEXT
_3 (table only)

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

78

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 37 — MODE - OPERATING MODES (cont)

ITEM EXPANSION RA NGE UNITS

HEAT Heat Mode Diagnostic HEATDIAG

HEAT In Heating Mode? Yes / No IN_HEAT
OK.HT OK to Select Heat Mode? Ye s /No OKTOHEAT
MS.TG Mode Select Timeguard xxx secs HEATMSTG
H.LOC Heat OAT Lockout Ye s/ N o HEATLOCK
HT.LO Heating Lockout Temp xxx dF OATLHEAT
IDF Indoor Fan State On/Off IDFSTATE
F.SPD Commanded Fan Speed xxx FANSPEED
AVL.H Available Heating Stages x AVLHSTGS
REQ.H Requested Heating Stages x REQHSTGS
LMT.H Max Heat Stage In Effect x HSTGLIMT
ACT.H Actual Heating Stages x ACTHSTGS
HT.1 Heat Stage 1 Relay On/Off HEAT_1
HT.2 Heat Stage 2 Relay On/Off HEAT_2
SAT Supply Air Temperature

SAT.H SAT Heat Mode Sensing Enable/Disable SAT_HEAT
SAT Supply Air Temperature xxx.x dF SAT_DISP
SAM.L Maximum SAT Lower Level xxx dF SATMAX_L
SAM.U Maximum SAT Upper Level xxx dF SATMAX_H

SPT Space Temperature

SPT Space Temperature xxx.x dF SPACE_T forcible
DMD.H Heating Demand xxx.x dF HEAT_DMD
TRND Spacetemp Trend (F/min) xxx.x SPTTREND
HT.PD SPT Heat Demand (+)

HT.ND SPT Heat Demand (--- )

ECON Economizer Diagnostic ECONDIAG

DMD.L Demand Limiting DMDL

( D i s p l a y T R I M --- s e e

Configuration)

H.LAG Heat Thermal Lag Factor x.x min HEAT_LAG

EC.EN Economizer Installed Ye s /No ECONO
OCC Currently Occupied Yes / No OCCUPIED forcible forcible
IDF Indoor Fan State On/Off IDFSTATE
F.SPD Commanded Fan Speed NNN FANSPEED
COOL In Cooling Mode? Yes/ No IN_COOL
E.LOC Econo Cool OAT Lockout Yes/ No ECONLOCK
EH.LO Econo Cool Hi Temp Limit xxx dF OATLECLH
EL.LO Econo Cool Lo Temp Limit xx dF OATLECLL
FC.LO Free Cool Low Temp Limit xx dF OATLUEFC
EN.LO Econo Cool Enth Lockout Ye s /No ENTHLOCK
EC.MX Econo Cool Max Position xxx % ECONOMAX
AQ.DV IAQ DCV Mode Yes /N o IN_IAQDV
AQ.MN Econo Min IAQ Position xxx % IAQMINP
AQ.OV IAQ Override Mode Yes /N o IN_IAQOV
OVR.P IAQ Override Position xxx % IAQOVPOS
AQ.LO OAQ Lockout Mode Ye s /N o IN_OAQLO
OAQ.L OAQ Lockout Limit xxxx OAQLOCK
LP.OV Lo Refrig Press Override Ye s/N o IN_LPOV
EC.CP Econo Commanded

EC.AP Econo Actual Position xxx % ECONOPOS
EC.MP MinPositioninEffect xxx % MIN_POS forcible
C.ANG Actuato r Control Angle CTLANGLE
E.CAL Economizer Calibrating Yes/ No ECOINCAL

D.LMT Demand Limit In Effect Ye s/ N o MODEDMDL
LMT.C Max Capacity In Effect xxx CAPLIMIT
LMT.H Max Heat Stage In Effect x HSTGLIMT
REDL Redline Activated Ye s/N o MODEREDL
SHED Loadshed Activated Yes /No MODESHED
MAX.C Max Compressor Capacity x MAX_CAPC forcible
MAX.H Max Allowed Heat Stages x MAXHSTGS forcible

Level

Level

Positio n

Sensor Ca librat ion TRIM

Space Temp Calibration ---30 to 130 dF SPT_CAL forcible
Space Temp Trim --- 30 to 30 ^F SPT_OFF forcible
Supply Air Temp Calib. --- 30 to 130 dF SAT_CAL forcible
Supply Air Temp Trim --- 30 to 30 ^F SAT_OFF forcible
Return Air Temp Calib. --- 30 to 130 dF RAT_CAL forcible
Return Air Temp Trim --- 30 to 30 ^F RAT_OFF forcible

xx.x ^F HDEM_POS

xx.x ^F HDEM_NEG

xxx % ECONOCMD forcible

CCN

TABL E/ SUB ---TABLE

CCN POINT

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

48/50PD

79

APPENDIX A - LOCAL DISPLAY AND CCN TABLES (CONT)

Table 37 — MODE - OPERATING MODES (cont)

ITEM EXPANSION RA NGE UNITS

(OCCDEFM = CCN only) Occupancy Supervisory OCCDEFM

(LINKDATA = CCN only) CCN --- Linkage LINKDATA

48/50PD

Current Mode (1=Occup) 0,1 MODE
CurrentOccupPeriod# 0to8 PER_NO
T i m e --- O v e r r i d e i n E f f e c t Ye s /No OVERLAST
Time--- Override Duration 0to4 hours OVR_HRS
Current Occupied Time xx.xx hh:mm STRTTIME
Current Unoccupied Time xx.xx hh:mm ENDTIME
Next Occupied Day NXTOCDAY
Next Occupied Time xx.xx hh:mm NXTOCTIM
Next Unoccupied Day NXTUNDAY
Next Unoccupied Time xx.xx hh:mm NXTUNTIM
Previous Unoccupied Day PRVUNDAY
Previous Unoccupied Time xx.xx hh.mm PRVUNTIM

Supervisory Element # xxx S U P E --- A D R
Supervisory Bus xxx S U P E --- B U S
Supervisory Blo ck Number xxx BLOCKNUM
Average Occup. Heat Stp. xxxx.x dF AOH S
Average Occup. Cool Stp. xxxx.x dF AOCS
Average Unocc. Heat Stp. xxxx.x dF AUHS
Average Unocc. Cool Stp. xxxx.x dF AUCS
AverageZoneTemperature xxxx.x dF AZT
Average Occup. Zone Temp xxxx.x dF AOZT
Linkage System Occupied? Yes/ No LO CC
Next Occupied Day ”Mon”, ”Tue”,

Next Occupied Time xx:xx hh:mm LNEXTOCC forcible
Next Unoccupied Day ”Mon”, ”Tue”,

Next Unoccupied Time xx:xx hh:mm LNEXTUNC forcible
Last Unoccupied Day ”Mon”, ”Tue”,

Last Unoccupied Time xx:xx hh:mm LLASTUNC forcible

& , ”Sun”

& , ”Sun”

& , ”Sun”

3 --- c h a
rtext

3 --- c h a
rtext

3 --- c h a
rtext

CCN

TABL E/ SUB ---TABLE

CCN POINT

LNEXTOCD

LNEXTUOD

LLASTUOD

CCN

WRITE

STATUS

DISPLAY

WRITE

STATUS

Table 38 — MODE - ALARMS

ITEM EXPANSION RANGE DEFAULT

ALARMS ALARMS

R.CUR Reset All Current Alarms Yes/ N o No ALRESET forcible forcible
R.HIS Reset Alarm History Ye s/ N o No ALHISCLR forcible forcible
CURR Currently Active Alarms

alarm# text string ALARM01C ---

(repeat up to 25

alarms)

HIST Alarm History ALARM HISTORY

alarm# alarm#--- mm/dd/yy --- hh.mm

(repeat up to 20

Alarms)

--- t e x t s t r i n g

CCN

TABL E/ SUB ---TABLE

MAINTENANCE
DISPLAY

CCN POINT

ALARM25C

CCN WRITE

STATUS

DISPLAY

WRITE

STATUS

80

APPENDIX B - VFD INFORMATION

On 48/50PD units, the supply fan speed is controlled by a 3 -- phase
VFD. The VFD is located in the supply fan section behind an
indoor fan scroll. The VFD speed is controlled directly by the
ComfortLinkt controls through a 0--10Vdc signal based on a
space temperature sensor. The VFD has a display, which can be
used for service diagnostics, but setup of the control is to be done
through the scrolling marquee display.

Table 39 — VFD TERMINAL DESIGNATIONS

TERMINAL FUNCTION

U1

V1

W1 Three --- Phase main circuit input power supply

U2

V2 Three --- Phase AC output to motor, 0V to maximum input

W2 voltage level

X 1 --- 1 1 ( G N D )

X 1 --- 1 2 ( C O M M O N ) Factory---supplied jumper

X1--- 10 (24VDC)

X 1 --- 1 3 ( D I --- 1 ) Run (factory---supplied jumper)

X1--- 10 (24VDC) Start Enable 1 (factory--- supplied jumper). When opened,

X 1 --- 1 6 ( D I --- 4 ) the drive goes to emergency stop

X 1 --- 2 ( A I --- 1 )

X 1 --- 3 ( A G N D ) Factory wired for 0---10Vdc remote input

The VFD is powered during normal operation to prevent
condensation from forming on the boards during the off mode and
is stopped by driving the speed to 0 (by sending a 0Vdc signal to
the VFD). The units use ABB VFDs. The interface wiring for the
VFDs is shown in the figure below. The VFD connects to
ComfortLink through a 0-- 10Vdc output on the AUX1 board.
Terminal designations are shown in the Terminal Designation table.
Configurations are shown in the VFD Configurations table.

48/50PD

0-10Vdc

A48-7712

C08674

Fig. 40 -- VFD Wiring

81

APPENDIX B - VFD INFORMATION (CONT)

Table 40 — VFD CONFIGURATIONS

APPLICATION CRITICAL DRIVE PARAMETERS FOR ABB ACH550 DRIVES

Parameter Group

S T A R T --- U P

DATA

48/50PD

START/STOP/DIR

ANALOG INPUTS

RELAY OUTPUTS

SYSTEM

CONTROL

OVER RIDE

LIMITS

START/STOP

ACCEL/DECEL

MOTOR

FAULT

FUNCTIONS

All Other Parameter Settings are ABB Drive Default Settings

Parameter

Number

9901 Language (0) English --- ABB Drive default

9902 Application Macro (1) HVAC Default ---

9904 Motor Control Mode (3) Scalar : Freq --- ABB Drive default

9905 Motor Nominal Voltage 230 460 Volts

9906 Motor Nominal Current 7.0 3.5 Amps

9907 Motor Nominal Frequency 60 Hz ABB Drive default

9908 Motor Nominal Speed 1725 RPM

9909 Motor Nominal Power 2.4 HP

1001 EXT1 Commands (1) DI --- 1 Start/Stop --- ABB Drive default

1002 EXT2 Commands (1) DI --- 1 Start/Stop --- ABB Drive default

1003 Direction (1) Forward ---

1301 M i n i m u m A l --- 1 20 % ABB Drive defau lt

1302 M a x i m u m A l --- 1 100 % ABB Dr ive default

1401 Relay Output 1 (7) Started ---

1402 Relay Output 2 (2) Run --- ABB Drive default

1403 Relay Output 3 ( 3 ) F a u l t ( --- 1 ) --- ABB Drive default

1601 Run Enable (0) Not Set --- ABB Drive default

1608 Start Enable 1 ( 4 ) D I --- 4 --- ABB Drive defau lt

1701 Override Set (3 ) D I --- 3 ---

1702 Override Freq 60 Hz

1703 Override Speed 1750 RPM

1704 Over Pass Code 0 ---

1705 Override On ---

2003 Maximum Current 8.0 4.0 Amps

2007 Minimum Frequency 0 Hz ABB Drive default

2008 Maximum Frequency 60 Hz ABB Drive defau lt

2101 Start Function (8) Ramp ---

2102 Stop Function (2) Ramp ---

2202 Accelerate Time 30 Seconds ABB Drive default

2203 Decelerate Time 30 Seconds ABB D rive default

2601 Flux Optimization (1) On ---

2605 Volt/Freq Ratio (2) Squared ---

2606 Switching Frequency 8 kHz

3006 Motor Thermal Time 1050 Seconds

Description

HK30WA001 ---208/230V HK30WA008 --- 460V

Value

UNITS NOTE

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

Carrier default settings
from PPS

Carrier default settings
from PPS

Carrier default settings
from PPS

Carrier default settings
from PPS

Carrier default settings
from PPS

Carrier default settings
from PPS

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

PD Product specific
setting

Carrier default settings
from PPS

Carrier default settings
from PPS

Carrier default settings
from PPS

82

APPENDIX B - VFD INFORMATION (CONT)

VFD Operation

The VFD keypad is shown in Fig. 41. The function of SOFT
KEYS 1 and 2 change depending on what is displayed on the
screen. The function of SOFT KEY 1 matches the word in the
lower left--hand box on the display screen. The function of SOFT
KEY 2 matches the word in the lower right--hand box on the
display screen. If the box is empty, then the SOFT KEY does not
have a function on that specific screen. The UP and DOWN keys
are used to navigate through the menus. The OFF key is used to
turn off the VFD. The AUTO key is used to change control of the
drive to automatic control. The HAND key is used to change
control of the drive to local (hand held) control. The HELP button
is used to access the help screens.

For the VFD to operate on the 48/50PD units, the drive must be set
in AUTO mode. The word “AUTO” will appear in the upper left
hand corner of the VFD display. Press the AUTO button to set the
drive in AUTO mode.

C08675

Fig. 41 -- VFD Keypad

Start Up with Assistant

Initial start--up has been performed at the factory. Use of the start
up assistant will override factory VFD configurations. See below
to check that all parameters listed in VFD Configurations table are
correctly configured on the VFD.

Start Up by Changing Parameters Individually

Initial start--up is performed at the factory. To start up the VFD
with by changing individual parameters, perform the following
procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight PARAMETERS
on the display screen and press ENTER (SOFT KEY 2).

3. Use the UP or DOWN keys to highlight the desired
parameter group and press SEL (SOFT KEY 2).

4. Use the UP or DOWN keys to highlight the desired
parameter and press EDIT (SOFT KEY 2).

5. Use the UP or DOWN keys to change the value of the
parameter.

6. Press SAVE (SOFT KEY 2) to store the modified value.
Press CANCEL (SOFT KEY 1) to keep the previous value.
Any modifications that are not saved will not be changed.

7. Choose another parameter or press EXIT (SOFT KEY 1) to
return to the listing of parameter groups. Continue until all
the parameters have been configured and then press EXIT
(SOFT KEY 1) to return to the main menu.

IMPORTANT: The current parameter value appears above the
highlight parameter. To view the default parameter value, press the
UP and DOWN keys simultaneously. To restore the default factory
settings, select the application macro “HVAC Default.”

VFD Modes

The VFD has several different modes for configuring, operating,
and d iagnosing the VFD. The modes are:

S Standard Display mode ⎯ shows drive status information and

operates the drive

S Parameters mode ⎯ edits parameter values individually
S Start--up Assistant mode ⎯ guides the start up and

configuration

S Changed Parameters mode ⎯ shows all changed parameters
S Drive Parameter Backup mode ⎯ stores or uploads the

parameters

S Clock Set mode ⎯ sets the time and date for the drive
S I/O Settings mode ⎯ checks and edits the I/O settings

Standard Display Mode

Use the standard display mode to read information on the drive
status and operate the drive. To reach the standard display mode,
press EXIT until the LCD display shows status information as
described below. See Fig. 42.

The top line of the LCD display shows the basic status information
of the drive. The HAND icon indicates that the drive control is
local from the control panel. The AUTO icon indicates that the
drive is in remote control mode, such as the basic I/O (X1) or field
bus.

The arrow icon indicates the drive and motor rotation status. A
rotating arrow (clockwise or counterclockwise) indicates that the
drive is running and at set point and the shaft direction is forward
or reverse. A rotating blinking arrow indicates that the drive is
running but not at set point. A stationary arrow indicates that the
drive is stopped. For Carrier rooftop units, the correct rotation is
counterclockwise.

The upper right corner shows the frequency set point that the drive
will maintain.

Using parameter group 34, the middle of the LCD display can be
configured to display 3 parameter values. The default display
shows parameters 0103 (OUTPUT FREQ) in percentages, 0104
(CURRENT) in amperes, and 0120 (AI1) in milliamperes.

The bottom corners of the LCD display show the functions
currently assigned to the two soft keys. The lower middle displays
the current time (if configured to show the time).

The first time the drive is powered up, it is in the OFF mode. To
switch to local hand--held control and control the drive using the
control p anel, press and ho ld the HAND bu tton. Pressing the
HAND button switches the drive to hand control while keeping the
drive running. Press the AUTO button to switch to remote input
control. To start the drive press the HAND or AUTO buttons, to
stop the drive press the OFF button.

C08676

Fig. 42 -- Standard Display Example

48/50PD

83

APPENDIX B -- VFD INFORMATION (CONT)

To adjust the speed in HAND mode, press the UP or DOWN
buttons (the reference changes immediately). The reference can be
modified in the local control (HAND) mode, and can be
parameterized (using Group 11 reference select) to also allow
modification in the remote control mode.

Parameters Mode

The Parameters mode is used to change the parameters on the
drive. To change parameters, perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight PARAMETERS
on the display screen and press ENTER (SOFT KEY 2).

3. Use the UP or DOWN keys to highlight the desired
parameter group and press SEL (SOFT KEY 2).

4. Use the UP or DOWN keys to highlight the desired
parameter and press EDIT (SOFT KEY 2).

5. Use the UP or DOWN keys to change the value of the
parameter.

48/50PD

6. Press SAVE (SOFT KEY 2) to store the modified value.
Press CANCEL (SOFT KEY 1) to keep the previous value.
Any modifications that are not saved will not be changed.

7. Choose another parameter or press EXIT (SOFT KEY 1) to
return to the listing of parameter groups. Continue until all
the parameters have been configured and then press EXIT
(SOFT KEY 1) to return to the main menu.

IMPORTANT: The current parameter value appears above the
highlight parameter. To view the default parameter value, press the
UP and DOWN keys simultaneously. To restore the default factory
settings, select the Carrier application macro.

Start--Up Assistant Mode

To use the Start--Up Assistant, perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight ASSISTANTS
on the display screen and press ENTER (SOFT KEY 2).

3. Use the UP or DOWN keys to highlight Commission
Drive and press SEL (SOFT KEY 2).

4. The Start--Up Assistant will display the parameters that need
to be configured. Select the desired values and press SA VE
(SOFT KEY 2) after every change. The process will
continue until all the parameters are set. The assistant checks
to make sure that entered values are in range.

The assistant is divided into separate tasks. The user can activate
the tasks one after the other or independently. The tasks are
typically done in this order: Application, References 1 and 2,
Start/Stop Control, Protections, Constant Speeds, PID Control,
Low Noise Setup, Panel Display, Timed Functions, and Outputs.

Changed Parameters Mode

The Changed Parameters mode is used to view and edit recently
changed parameters on the drive. To view the changed parameters,
perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight CHANGED PAR
on the display screen and press ENTER (SOFT KEY 2). A
list of the recently changed parameters will be displayed.

3. Use the UP or DOWN keys to highlight the desired
parameter group and press EDIT (SOFT KEY 2) to change
the parameter if desired.

4. Press EXIT (SOFT KEY 1) to exit the Changed Parameters
mode.

Drive Parameter Backup Mode

The drive parameter back up mode is used to export the parameters
from one drive to another. The parameters can be uploaded from a
VFD to the removable control panel. The control panel can then be
transferred to another drive and the parameters downloaded into
memory.

Depending on the motor and application, there are two options
available. The first option is to download all parameters. This
copies both application and motor parameters to the drive from the
control panel. This is recommended when using the same
application for drives of the same size. This can also be used to
create a backup of the parameters group for the drive.

The second option downloads only the application parameters to
the drive. This is recommended when using the same application
for drives of different sizes. Parameters 9905, 9906, 9907, 9908,
9909, 1605, 1607, 5201, and group 51 parameters and internal
motor parameters are not copied.

Upload All Parameters

To upload and store parameters in the control panel from the VFD,
perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight PAR BACKUP on
the display screen and press ENTER (SOFT KEY 2).

3. Use the UP o r DOWN keys to highlight UPLOAD TO
PANEL and press SEL (SOFT KEY 2).

4. The text “Copying Parameters” will be displayed with a
progress indicator. To stop the process, select ABORT
(SOFT KEY 1).

5. When the upload is complete, the text “Parameter upload
successful” will be displayed.

6. The display will then return to the PAR BACKUP menu.
Select EXIT (SOFT KEY 1) to return to the main menu.

7. The control panel can now be disconnected from the drive.

Download All Parameters

To download all parameters from the control panel to the VFD,
perform the following procedure:

1. Install the control panel with the correct parameters onto the
VFD.

2. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

3. Use the UP or DOWN keys to highlight PAR BACKUP on
the display screen and press ENTER (SOFT KEY 2).

4. Use the UP or DOWN keys to highlight DOWNLOAD TO
DRIVE ALL and press SEL (SOFT KEY 2 ).

5. The text “Restoring Parameters” will be displayed with a
progress indicator. To stop the process, select ABORT
(SOFT KEY 1).

6. When the download is complete, the text “Parameter
download successful” will be displayed.

7. The display will then return to the PAR BACKUP menu.
Select EXIT (SOFT KEY 1) to return to the main menu.

8. The control panel can now be disconnected from the drive.

84

Download Application Parameters

To download application parameters only to the control panel from
the VFD, perform the following procedure:

1. Install the control panel with the correct parameters onto the
VFD.

2. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

3. Use the UP or DOWN keys to highlight PAR BACKUP on
the display screen and press ENTER (SOFT KEY 2).

4. Use the UP o r DOWN keys to highlight DOWNLOAD
APPLICA TION and press SEL (SOFT KEY 2).

5. The text “Downloading Parameters (partial)” will be
displayed with a progress indicator. To stop the process,
select ABORT (SOFT KEY 1).

6. When the download is complete, the text “Parameter
download successful” will be displayed.

7. The display will then return to the PAR BACKUP menu.
Select EXIT (SOFT KEY 1) to return to the main menu.

8. The control panel can now be disconnected from the drive.

Clock Set Mode

The clock set mode is used for setting the date and time for the
internal clock of the VFD. In order to use the timer functions of the
VFD control, the internal clock must be set. The date is used to
determine weekdays and is visible in the fault logs.

To set the clock, perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight CLOCK SET on
the display screen and press ENTER (SOFT KEY 2). The
clock set parameter list will be displayed.

3. Use the UP or DOWN keys to highlight CLOCK
VISIBILITY and press SEL (SOFT KEY 2). This
parameter is used to display or hide the clock on the screen.
Use the UP or DOWN keys to change the parameter setting.
Press OK (SOFT KEY 2) to save the configuration and
return to the Clock Set menu.

4. Use the UP or DOWN keys to highlight SET TIME and
press SEL (SOFT KEY 2). Use the UP or DOWN keys to
change the hours and minutes. Press OK (SOFT KEY 2) to
save the configuration and return to the Clock Set menu.

5. Use the UP or DOWN keys to highlight TIME FORMAT
and press SEL (SOFT KEY 2). Use the UP or DOWN keys
to change the parameter setting. Press OK (SOFT KEY 2)
to save the configuration and return to the Clock Set menu.

6. Use the UP or DOWN keys to highlight SET DATE and
press SEL (SOFT KEY 2). Use the UP or DOWN keys to
change the day, month, and year. Press OK (SOFT KEY 2)
to save the configuration and return to the Clock Set menu.

7. Use the UP or DOWN keys to highlight DATE FORMAT
and press SEL (SOFT KEY 2). Use the UP or DOWN keys
to change the parameter setting. Press OK (SOFT KEY 2)
to save the configuration and return to the Clock Set menu.

8. Press EXIT (SOFT KEY 1) twice to return to the main
menu.

I/O Settings Mode

The I/O Settings mode is used for viewing and editing the I/O
settings.

To configure the I/O settings, perform the following procedure:

1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.

2. Use the UP or DOWN keys to highlight I/O SETTINGS on
the display screen and press ENTER (SOFT KEY 2). The
I/O Settings parameter list will be displayed.

3. Use the UP or DOWN keys to highlight the desired I/O
setting and press SEL (SOFT KEY 2).

4. Use the UP or DOWN keys to select the parameter to view.
Press OK (SOFT KEY 2).

5. Use the UP or DOWN keys to change the parameter setting.
Press SAVE (SOFT KEY 2) to save the configuration. Press
CANCEL (SOFT KEY 1) to keep the previous value. Any
modifications that are not saved will not be changed.

6. Press EXIT (SOFT KEY 1) twice to return to the main
menu.

VFD Diagnostics

The drive detects error situations and reports them using:

S Green and red LEDs on the body of the drive (located under the

keypad)

S Status LED on the control panel
S Control panel display
S The Fault Word and Alarm Word parameter bits (parameters

0305 to 0309)

The form of the display depends on the severity of the error. The
user can specify the severity for many errors by directing the drive
to ignore the error situation, report the situation as an alarm, or
report the situation as a fault.

Faults (Red LED Lit)

The VFD signals that it has detected a severe error, or fault, by:

S Enabling the red LED on the drive (LED is either steady or

flashing)

S Setting an appropriate bit in a Fault Word parameter (0305 to

0307)

S Overriding the control panel display with the display of a fault

code

S Stopping the motor (if it was on)
S Sets an appropriate bit in Fault Word parameter 0305 -- 0307.

The fault code on the control panel display is temporary. Pressing
the MENU, ENTER, UP button or DOWN buttons removes the
fault message. The message reappears after a few seconds if the
control panel is not touched and the fault is still active.

Alarms (Green LED Flashing)

For less severe errors, called alarms, the diagnostic display is
advisory. For these situations, the drive is simply reporting that it
had detected something unusual. In these situations, the drive:

S Flashes the green LED on the drive (does not apply to alarms

that arise from control panel operation errors)

S Sets an appropriate bit in an Alarm Word parameter (0308 or

0309)

S Overrides the control panel display with the display of an alarm

code and/or name

Alarm messages disappear from the control panel display after a
few seconds. The message returns periodically as long as the alarm
condition exists.

Correcting Faults

The recommended corrective action for faults is shown in the Fault
Listing Table 41. The VFD can also be reset to remove the fault. If
an external source for a start command is selected and is active, the
VFD may start immediately after fault reset.

To reset a fault indicated by a flashing red LED, turn off the power
for 5 minutes. To reset a fault indicated by a red LED (not
flashing), p ress RESET from the control panel or turn off the
power for 5 minutes. Depending on the value of parameter 1604
(FAULT RESET SELECT), digital input or serial communication
could also be used to reset the drive. When the fault has been
corrected, the motor can be started.

48/50PD

85

History

For reference, the last three fault codes are stored into parameters
0401, 0412, 0413. For the most recent fault (identified by
parameter 0401), the drive stores additional data (in parameters
0402 through 0411) to aid in troubleshooting a problem. For
example, a parameter 0404 stores the motor speed at the time of the
fault. To clear the fault history (all of Group 04, Fault History
parameters), follow these steps:

1. In the control panel, Parameters mode, select parameter

0401.

2. Press EDIT.

3. Press the UP and DOWN buttons simultaneously.

4. Press SAVE.

Correcting Alarms

To correct alarms, first determine if the Alarm requires any
corrective action (action is not always required). Use Table 42 to
find and address the root cause of the problem.

If diagnostics troubleshooting has determined that the drive is
defective during the warranty period, contact ABB Automation

48/50PD

Inc., at 1--800-- 435--7365, option 4, option 3. A qualified
technician will review the problem with the caller and make a
determination regarding how to proceed. This may involve
dispatching a designated service station (DSS) representative from
an authorized station, dispatching a replacement unit, or advising
return for repair.

VFD Maintenance

If installed in an appropriate environment, the VFD requires very
little maintenance.

Table 43 lists the routine maintenance intervals recommended by
Carrier.

Heat Sink

The heat sink fins accumulate dust from the cooling air. Since a
dusty sink is less efficient at cooling the drive, overtemperature
faults become more likely. In a normal environment check the heat
sink annually, in a dusty environment check more often.

Check the heat sink as follows (when necessary):

1. Remove power from drive.

2. Remove the cooling fan.

3. Blow clean compressed air (not humid) from bottom to top
and simultaneously use a vacuum cleaner at the air outlet to
trap the dust. If there a risk of the dust entering adjoining
equipment, perform the cleaning in another room.

4. Replace the cooling fan.

5. Restore power.

86

APPENDIX B - VFD INFORMATION (CONT)

Table 41 — FAULT CODES

FAULT
CODE

10

11 ID RUN FAIL The motor ID run was not completed successfully. Check motor connections.

12

13 RESERVED Not used.

14 EXT FAULT 1 Digital input defined to report first external fault is active. See parameter 3003 EXTERNAL FAULT 1.

15 EXT FAULT 2 Digital input defined to report second external fault is active. See parameter 3004 EXTERNAL FAULT 2.

16

17

18 THERM FAIL Internal fault. The thermistor measuring the internal temperature of the drive is open or shorted. Contact Carrier.

19

20 OPEX PWR Internal fault. Low voltage condition detected on the OINT board. Contact Carrier.

21 CURR MEAS Internal fault. Current measurement is out of range. Contact Carrier.

22 SUPPLY PHASE Ripple voltage in the DC link is too high. Check for missing main phase or blown fuse.

23 RESERVED Not used.

24

25 RESERVED Not used.

26 DRIVE ID Internal fault. Configuration block drive ID is not valid.

27 CONFIG FILE Internal configuration file has an error. Contact Carrier.

28

29 EFB CON FILE Error in reading the configuration file for the field bus adapter.

30 FORCE TRIP Faulttripforcedbythefieldbus.Seethefieldbusreferenceliterature.

31 EFB 1 Fault code reserved for the EFB protocol application. The meaning is protocol dependent.

32 EFB 2 Fault code reserved for the EFB protocol application. The meaning is protocol dependent.

33 EFB 3 Fault code reserved for the EFB protocol application. The meaning is protocol dependent.

34

35 OUTP WIRING Error in power wiring suspected. Check that input power wired to drive output. Check for ground faults.

101--- 105 SYSTEM ERROR Error internal to the drive. Contact Carrier and report the error number.

201--- 206 SYSTEM ERROR Error internal to the drive. Contact Carrier and report the error number.

FAULT NAME IN PANEL DESCRIPTION AND RECOMMENDED CORRECTIVE ACTION

1

2

3

4 SHORT CIRC Fault current. Check for short---circuit in the motor cable(s) or motor or supply disturbances.

5 OVERLOAD Inverter overload condition. The drive output current exceeds the ratings.

6

7

8

9

OVERCURRENT

DC OVERVOLT

DEV OVERTEMP

DC OVERVOLT

Al1 LOSS

Al2 LOSS

MOT OVERTEMP

PAN E L L OSS

MOTOR STALL

EARTH FAULT

UNDERLOAD

OPEX LINK

OVERSPEED

SERIAL 1 ERR

MOTOR PHASE

Output current is excessive. Check for excessive motor load, insufficient acceleration time (parameters 2202
ACCELER TIME 1, default 30 seconds), or faulty motor, motor cables or connections.

Intermediate circuit DC voltage is excessive. Check for static or transient over voltages in the input power supply,
insufficient deceleration time (parameters 2203 DECELER TIME 1, default 30 seconds), or undersized brake chopper
(if present).

Drive heat sink is overheated. Temperature is at or above 115_C (239_F). Check for fan failure, obstructions in the air
flow,dirtordustcoatingontheheatsink,excessiveambienttemperature,orexcessivemotorload.

Intermediate circuit DC voltage is not sufficient. Check for missing phase in the input power supply, blown fuse, or
under voltage on main circuit.

Analog input 1 loss. Analog input value is less than AI1 FLT LIMIT (3021). Check source and connection for analog
input and parameter settings for AI1 FLT LIMIT (3021) and 3001 AI<MIN FUNCTION.

Analog input 2 loss. Analog input value is less than AI2 FLT LIMIT (3022). Check source and connection for analog
input and parameter settings for AI2 FLT LIMIT (3022) and 3001 AI<MIN FUNCTION.

Motor is too hot, as estimated by the drive. Check for overloaded motor. Adjust the parameters used for the estimate
(3005 through 3009). Check the temperature sensors and Group 35 parameters.

Panel communication is lost and either drive is in local control mode (the control panel displays LOC), or drive is in
remote control mode (REM) and is parameterized to accept start/stop, direction or reference from the control panel.
To correct check the communication lines and connections. Check parameter 3002 PANEL COMM ERROR,
parameters in Group 10: Command Inputs and Group 11:Reference Select (if drive operation is REM).

Motor or process stall. Motor is operating in the stall region. Check for excessive load or insufficient motor power.
Check parameters 3010 through 3012.

The load on the input power system is out of balance. Check for faults in the motor or motor cable. Verify that motor
cable does not exceed maximum specified length.

Motor load is lower than expected. Check for disconnected load. Check parameters 3013 UNDERLOAD FUNCTION
through 3015 UNDERLOAD CURVE.

Internal fault. A communication --- related problem has been detected between the OMIO and OINT boards. Contact
Carrier.

Motor speed is greater than 120% of the larger (in magnitude) of 2001 MINIMUM SPEED or 2002 MAXIMUM SPEED
parameters. Check parameter settings for 2001 and 2002. Check adequacy of motor braking torque. Check
applicability of torque control. Check brake chopper and resistor.

Field bus communication has timed out. Check fault setup (3018 COMM FAULT FUNC and 3019 COMM FAULT
TIME). Check communication settings (Group 51 or 53 as appropriate). Check for poor connections and/or noise on
line.

Fault in the motor circuit. One of the motor phases is lost. Check for motor fault, motor cable fault, thermal relay fault ,
or internal fault.

48/50PD

87

APPENDIX B - VFD INFORMATION (CONT)

Table 41 — FAUL T CODES (cont)

FAULT
CODE

1000

1001 PAR PFA R E FNG Parameter values are inconsistent. Check that 2007 MINIMUM FREQ is negative, when 8123 PFA ENABLE is active.

1002

1003

1004

1005

48/50PD

1006

1007

1008

1009

1010 OVERRIDE/PFA

FAULT NAME IN PANEL DESCRIPTION AND RECOMMENDED CORRECTIVE ACTION

Parameter values are inconsistent. Check for any of the following:
2001 MINIMUM SPEED > 2002 MAXIMUM SPEED
2007 MINIMUM FREQ > 2008 MAXIMUM FREQ

PAR H Z RP M

PAR P FA IO C NF

PAR A I S C AL E

PAR A O S C AL E

PAR P C U 2

PAR E X T RO

PAR F B U S

PAR P FA MO D E

PAR P C U 1

CONFLICT

2001 MINIMUM SPEED / 9908 MOTOR NOM SPEED is outside of the range: --- 128/+128
2002 MAXIMUM SPEED / 9908 MOTOR NOM SPEED is outside of the range: --- 128/+128
2007 MINIMUM FREQ / 9907 MOTOR NOM FREQ is outside of the range: --- 128/+128
2008 MAXIMUM FREQ / 9907 MOTOR NOM FREQ is outside of the range: --- 128/+128

Parameter values are inconsistent. The number of programmed PFA relays does not match with Interlock
configuration, when 8123 PFA ENABLE is active. Check consistency of RELAY OUTPUT parameters 1401 through
1403, and 1410 through 1412. Check 8117 NR OF AUX MOTORS, 8118 AUTOCHANGE INTERV, and 8120
INTERLOCKS.

Parameter values are inconsistent. Check that parameter 1301 AI 1 MIN > 1302 AI 1 MAX and that parameter 1304 AI
2 MIN > 1305 AI 2 MAX.

Parameter values are inconsistent. Check that parameter 1504 AO 1 MIN > 1505 AO 1 MAX and that parameter 1510
AO 2 MIN > 1511 AO 2 MAX.

Parameter values for power control are inconsistent: Improper motor nominal kVA or motor nominal power. Check the
following parameters:

1.1 < (9906 MOTOR NOM CURR * 9905 MOTOR NOM VOLT * 1.73 / PN) < 2.6
Where: PN = 1000 * 9909 MOTOR NOM POWER (if units are kW) or PN = 746
* 9909 MOTOR NOM POWER (if units are HP, e.g., in US)

Parameter values are inconsistent. Check the extension relay module for connection and 1410 through 1412 RELAY
OUTPUTS 4 through 6 have non---zero values.

Parameter values are inconsistent. Check that a parameter is set for field bus control (e.g., 1001 EXT1 COMMANDS =
10 (COMM)), but 9802 COMM PROT SEL = 0.

Parameter values are inconsistent. The 9904 MOTOR CTRL MODE must = 3 (SCALAR SPEED) when 8123 PFA
ENABLE activated.

Parameter values for power control are inconsistent or improper motor nominal frequency or speed. Check for both
of the following:
1 < (60 * 9907 MOTOR NOM FREQ / 9908 MOTOR NOM SPEED < 16

0.8 < 9908 MOTOR NOM SPEED / (120 * 9907 MOTOR NOM FREQ / Motor poles) < 0.992

Override mode is enabled and PFA is activated at the same time. This cannot be done because PFA interlocks cannot
be observed in the override mode.

88

APPENDIX B - VFD INFORMATION (CONT)

Table 42 — ALARM CODES

ALARM

CODE

2001 --- Reserved

2002 --- Reserved

2003 --- Reserved

2004 DIR LOCK

2005 I/O COMM

2006 Al 1 LOSS

2007 Al 2 LOSS

2008 PAN E L L OS S

2009 --- Reserved

2010 MOT OVERTEMP

2011 UNDERLOAD

2012 MOTOR STALL Motor is operating in the stall region. This alarm warns that a Motor Stall fault trip may be near.

2013* AU TORESET

2014 AU TOCHAN GE

2015 PFA INTERLOCK

2016 --- Reserved

2017* OFF BUTTON This alarm indicates that the OFF button has been pressed.

2018 PID SLEEP

2019 ID RUN The VFD is performing an ID run.

2020 OVERRIDE Override mode is activated.

2021

2022

2023 EMERGENCY STOP Emergency stop is activated.

* This alarm is not indicated by a relay output, even when the relay output is configured to indicate alarm conditions, parameter 1401 RELAY OUTPUT = 5 (ALARM)or16
(FLT/ALARM).

ALARM NAME

IN PANEL

START ENABLE 1

MISSING

START ENABLE 2

MISSING

DESCRIPTION AND RECOMMENDED CORRECTIVE ACTION

The change in direction being attempted is not allowed. Do not attempt to change the direction of motor rotation, or
Change parameter 1003 DIRECTION to allow direction change (if reverse operation is safe).

Field bus communication has timed out. Check fault setup (3018 COMM FAULT FUNC and 3019 COMM FAULT
TIME). Check communication settings (Group 51 or 53 as appropriate). Check for poor connections and/or noise on
line.

Analog input 1 is lost, or value is less than the minimum setting. Check input source and connections. Check the
parameter that sets the minimum (3021) and the parameter that sets the Alarm/Fault operation (3001).

Analog input 2 is lost, or value is less than the minimum setting. Check input source and connections. Check
parameter that sets the minimum (3022) and the parameter that sets the Alarm/Fault operation (3001).

Panel communication is lost and either the VFD is in local control mode (the control panel displays HAND), or the
VFD is in remote control mode (AUTO) and is parameterized to accept start/stop, direction or reference from the
control panel. To correct, check the communication lines and connections, Parameter 3002 PANEL LOSS, and
parameters in groups 10 COMMAND INPUTS and 11 REFERENCE SELECT (if drive operation is REM).

Motor is hot, based on either the VFD estimate or on temperature feedback. This alarm warns that a Motor Overload
fault trip may be near. Check for overloaded motor. Adjust the parameters used for the estimate (3005 through 3009).
Check the temperature sensors and Group 35 parameters.

Motor load is lower than expected. This alarm warns that a Motor Underload fault trip may be near. Check that the
motor and drive ratings match (motor is NOT undersized for the drive). Check the settings on parameters 3013 to

3015.

This alarm warns that the drive is about to perform an automatic fault reset, which may start the motor. To
control automatic reset, use parameter group 31 (AUTOMATIC RESET).

This alarm warns that the PFA autochange function is active. To control PFA, use parameter group 81 (PFA) and the
Pump Alternation macro.

This alarm warns that the PFA interlocks are active, which means that the drive cannot start any motor (when
Autochange is used), or a speed regulated motor (when Autochange is not used).

This alarm warns that the PID sleep function is active, which means that the motor could accelerate when the PID
sleep function ends. To control PID sleep, use parameters 4022 through 4026 or 4122 through 4126.

This alarm warns that the Start Enable 1 signal is missing. To control Start Enable 1 function, use parameter 1608. To
correct, check the digital input configuration and the communication settings.

This alarm warns that the Start Enable 2 signal is missing. To control Start Enable 2 function, use parameter1609. To
correct, check the digital input configuration and the communication settings.

48/50PD

Table 43 — MAINTENANCE INTERVALS

MAINTENANCE INTERVAL

Heat sink temperature check and
cleaning

Main cooling fan replacement Every five years

HVAC Control panel battery change Every ten years

Every 6 to 12 months (depending
on the dustiness of the
environment)

89

APPENDIX B - VFD INFORMATION (CONT)

Main Fan Replacement

The main cooling fan of the VFD has a life span of about 60,000
operating hours at maximum rated operating temperature and drive
load. The expected life span doubles for each 18 F drop in the fan
temperature (fan temperature is a function of ambient temperatures
and drive loads).

Fan failure can be predicted by the increasing noise from fan
bearings and the gradual rise in the heat sink temperature in spite of
heat sink cleaning. If the drive is operated in a critical part of a
process, fan replacement is recommended once these symptoms
start appearing. Replacement fans are available from Carrier.

To replace the main fan for frame sizes R1 through R2, perform the
following (see Main Fan Replacement figure):

1. Remove power from drive.

2. Remove drive cover.

3. For frame sizes R1 and R2, press together the retaining clips
on the fan cover and lift.

4. Disconnect the fan cable.

48/50PD

5. Install the new fan by reversing Steps 2 to 4.

6. Restore power.

Control Panel Cleaning

Use a soft damp cloth to clean the control panel. Avoid harsh
cleaners which could scratch the display window.

Battery Replacement

A battery is only used in assistant control panels that have the clock
function available and enabled. The battery keeps the clock
operating in memory during power interruptions. The expected life
for the battery is greater than ten years. To remove the battery, use
a coin to rotate the battery holder on the back of the control panel.
Replace the battery with type CR2032.

3

3

4

2

C08681

Fig. 43 -- Main Fan Replacement

(Frame Sizes R1--R2)

90

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

APPENDIX C -- START--UP DATA

Table 44 — Fan Performance - 48PDD05 Vertical Units

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

504 0.16 613 0.23 710 0.31 798 0.40 881 0.49
527 0.19 632 0.27 725 0.35 810 0.44 890 0.54
551 0.22 652 0.31 741 0.40 823 0.49 900 0.59
576 0.26 673 0.35 759 0.44 838 0.54 912 0.65
600 0.30 694 0.40 777 0.50 854 0.60 926 0.71
626 0.35 716 0.45 797 0.55 871 0.66 941 0.78
651 0.40 739 0.51 817 0.62 889 0.73 957 0.85
677 0.46 762 0.57 838 0.69 908 0.80 974 0.93
703 0.52 785 0.64 859 0.76 927 0.88 992 1.01

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

LEGEND
Bhp -- Brake Horsepower

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

957 0.59 1030 0.70 1098 0.80 1163 0.91 1225 1.03
964 0.64 1035 0.75 1102 0.86 1166 0.98 1227 1.10
973 0.70 1042 0.81 1107 0.92 1170 1.04 1231 1.17
983 0.76 1050 0.87 1114 0.99 1176 1.12 1235 1.24

994 0.82 1060 0.94 1122 1.06 1183 1.19 1241 1.32
1007 0.89 1071 1.02 1132 1.14 1191 1.27 1248 1.41
1021 0.97 1083 1.10 1143 1.23 1200 1.36 1256 1.50
1037 1.05 1097 1.18 1155 1.32 1211 1.45 1266 1.60
1053 1.14 1111 1.27 1168 1.41 1223 1.55 1276 1.70

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

Table 45 — Fan Performance - 48PDE05 Vertical Units

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

509 0.16 618 0.24 714 0.32 802 0.41 884 0.50

533 0.19 637 0.27 730 0.36 814 0.45 894 0.55

557 0.23 658 0.31 746 0.40 828 0.50 905 0.60

582 0.27 679 0.36 764 0.45 843 0.55 917 0.66

608 0.31 701 0.40 783 0.50 860 0.61 931 0.72

634 0.36 723 0.46 803 0.56 877 0.67 947 0.79

660 0.41 747 0.52 824 0.63 896 0.74 963 0.86

686 0.47 770 0.58 846 0.70 915 0.82 981 0.94

713 0.54 795 0.66 868 0.78 935 0.90 999 1.02

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

961 0.60 1033 0.70 1101 0.81 1166 0.92 1228 1.03

968 0.65 1039 0.76 1106 0.87 1169 0.98 1230 1.10

977 0.70 1046 0.82 1111 0.93 1174 1.05 1234 1.17

987 0.77 1054 0.88 1118 1.00 1180 1.12 1239 1.25

999 0.83 1065 0.95 1127 1.07 1187 1.20 1245 1.33
1013 0.90 1076 1.03 1137 1.15 1196 1.28 1253 1.42
1027 0.98 1089 1.11 1148 1.24 1206 1.37 1261 1.51
1043 1.06 1103 1.20 1161 1.33 1217 1.47 1271 1.61
1060 1.16 1118 1.29 1175 1.43 1229 1.57 1282 1.72

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

48/50PD

91

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

Table 46 — Fan Performance - 48PDF05 Vertical Units

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

520 0.17 628 0.24 723 0.33 811 0.41 892 0.51

545 0.20 648 0.28 739 0.37 823 0.46 902 0.56

570 0.24 668 0.32 756 0.41 837 0.51 913 0.61

596 0.28 691 0.37 775 0.46 853 0.56 927 0.67

623 0.32 714 0.42 795 0.52 870 0.62 942 0.73

650 0.37 737 0.48 816 0.58 889 0.69 958 0.80

677 0.43 762 0.54 838 0.65 909 0.76 976 0.88

705 0.50 787 0.61 861 0.72 929 0.84 994 0.97

734 0.57 813 0.68 884 0.80 951 0.93 1014 1.06

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900

48/50PD

2000

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

968 0.61 1040 0.71 1108 0.82 1172 0.93 1233 1.04

976 0.66 1046 0.77 1112 0.88 1176 1.00 1237 1.11

985 0.72 1054 0.83 1119 0.95 1181 1.07 1241 1.19

996 0.78 1063 0.90 1127 1.02 1188 1.14 1247 1.27
1009 0.85 1074 0.97 1136 1.09 1196 1.22 1254 1.35
1024 0.92 1087 1.05 1147 1.17 1205 1.31 1262 1.44
1039 1.00 1100 1.13 1159 1.26 1216 1.40 1272 1.54
1056 1.09 1116 1.22 1173 1.36 1229 1.50 1283 1.64
1074 1.19 1132 1.32 1188 1.46 1242 1.61 1295 1.75

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

Table 47 — Fan Performance - 48PDD06 Vertical Units

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

593 0.27 688 0.37 773 0.46 851 0.56 925 0.67

620 0.32 711 0.42 793 0.52 868 0.62 939 0.73

646 0.37 734 0.47 813 0.58 886 0.69 955 0.80

673 0.43 758 0.53 835 0.64 905 0.76 972 0.88

700 0.49 783 0.60 857 0.72 925 0.84 990 0.96

728 0.56 807 0.68 879 0.80 946 0.92 1009 1.05

755 0.63 833 0.76 903 0.88 968 1.01 1029 1.14

783 0.71 858 0.84 926 0.97 990 1.11 1050 1.24

811 0.80 884 0.94 950 1.07 1012 1.21 1071 1.35

840 0.90 910 1.04 975 1.18 1035 1.33 1092 1.47

868 1.00 937 1.15 1000 1.30 1059 1.45 1115 1.60

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

995 0.78 1061 0.89 1125 1.01 1186 1.14 1245 1.26
1007 0.85 1072 0.96 1134 1.09 1194 1.22 1252 1.35
1021 0.92 1084 1.04 1145 1.17 1203 1.30 1260 1.44
1036 1.00 1098 1.13 1157 1.26 1214 1.39 1269 1.53
1053 1.08 1112 1.22 1170 1.35 1226 1.49 1280 1.63
1070 1.18 1128 1.31 1184 1.45 1238 1.60 1291 1.74
1088 1.28 1145 1.42 1199 1.56 1253 1.71 1304 1.86
1107 1.38 1162 1.53 1216 1.68 1268 1.83 1318 1.98
1127 1.50 1181 1.65 1233 1.80 1284 1.95 1333 2.11
1147 1.62 1200 1.77 1251 1.93 1300 2.09 1349 2.25
1168 1.75 1220 1.91 1270 2.07 1318 2.23 1365 2.40

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

92

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

Table 48 — Fan Performance - 48PDE06 Vertical Units

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

607 0.29 700 0.38 784 0.47 861 0.57 934 0.68

634 0.33 724 0.43 804 0.53 879 0.64 950 0.75

662 0.39 748 0.49 826 0.60 898 0.71 967 0.82

690 0.45 773 0.55 848 0.67 918 0.78 985 0.90

719 0.51 799 0.63 872 0.74 940 0.86 1004 0.98

748 0.59 825 0.70 896 0.83 962 0.95 1024 1.08

777 0.67 852 0.79 920 0.92 985 1.05 1045 1.18

807 0.75 879 0.88 946 1.01 1008 1.15 1067 1.29

837 0.85 907 0.98 971 1.12 1032 1.26 1090 1.40

867 0.95 935 1.09 998 1.24 1057 1.38 1113 1.53

897 1.06 963 1.21 1024 1.36 1082 1.51 1137 1.66

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

1004 0.79 1070 0.91 1133 1.03 1194 1.15 1253 1.28
1017 0.86 1081 0.98 1143 1.11 1203 1.24 1260 1.37
1032 0.94 1094 1.06 1155 1.19 1213 1.32 1269 1.46
1048 1.02 1109 1.15 1168 1.28 1224 1.42 1279 1.56
1066 1.11 1125 1.24 1182 1.38 1237 1.52 1291 1.66
1084 1.21 1142 1.35 1197 1.49 1251 1.63 1304 1.78
1104 1.31 1160 1.45 1214 1.60 1267 1.75 1318 1.90
1124 1.43 1179 1.57 1231 1.72 1283 1.87 1333 2.03
1145 1.55 1198 1.70 1250 1.85 1300 2.01 1349 2.17
1167 1.68 1219 1.83 1269 1.99 1318 2.15 1366 2.31
1189 1.82 1240 1.97 1290 2.14 1337 2.30 — —

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

Table 49 — Fan Performance - 48PDF06 Vertical Units

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

620 0.30 711 0.39 794 0.49 871 0.59 944 0.70

648 0.35 736 0.45 816 0.55 890 0.65 960 0.76

677 0.40 762 0.51 838 0.61 910 0.72 978 0.84

707 0.47 788 0.58 862 0.69 931 0.80 997 0.92

737 0.54 815 0.65 887 0.77 954 0.89 1017 1.01

767 0.61 843 0.73 912 0.85 977 0.98 1039 1.11

798 0.70 871 0.82 938 0.95 1001 1.08 1061 1.21

829 0.79 900 0.92 965 1.05 1026 1.19 1084 1.33

861 0.89 929 1.03 992 1.17 1052 1.31 1108 1.45

893 1.00 959 1.15 1020 1.29 1078 1.43 1133 1.58

925 1.12 989 1.27 1048 1.42 1105 1.57 1158 1.72

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

48/50PD

AIRFLOW

(CFM)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

1013 0.81 1078 0.92 1141 1.05 1202 1.17 1260 1.30
1027 0.88 1091 1.00 1152 1.13 1211 1.25 1269 1.39
1043 0.96 1105 1.08 1165 1.21 1222 1.35 1278 1.48
1060 1.05 1120 1.18 1179 1.31 1235 1.44 1290 1.59
1078 1.14 1137 1.27 1194 1.41 1249 1.55 1302 1.70
1098 1.24 1155 1.38 1210 1.52 1264 1.67 1316 1.81
1119 1.35 1174 1.49 1228 1.64 1280 1.79 1331 1.94
1140 1.47 1195 1.62 1247 1.77 1298 1.92 1348 2.08
1163 1.60 1216 1.75 1267 1.90 1317 2.06 1365 2.22
1186 1.73 1238 1.89 1288 2.05 1336 2.21 1384 2.37
1210 1.88 1261 2.04 1309 2.20 1357 2.37 — —

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

93

Table 50 — Fan Performance - 48PDD05 Horizontal Units

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900

48/50PD

2000

LEGEND
Bhp -- Brake Horsepower

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

436 0.12 559 0.19 661 0.27 753 0.35 839 0.45

456 0.14 574 0.22 673 0.30 762 0.39 845 0.49

477 0.17 592 0.25 687 0.34 774 0.43 853 0.53

500 0.20 611 0.29 703 0.38 787 0.48 864 0.58

523 0.24 631 0.33 721 0.43 801 0.53 877 0.63

548 0.28 652 0.38 739 0.48 818 0.58 891 0.69

573 0.32 674 0.43 759 0.54 835 0.64 906 0.76

600 0.37 697 0.48 779 0.60 854 0.71 923 0.83

627 0.43 720 0.55 801 0.67 873 0.79

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

918 0.54 993 0.64 1063 0.75 1130 0.86 1193 0.97

922 0.58 995 0.69 1064 0.80 1130 0.91 1193 1.03

929 0.63 1000 0.74 1067 0.85 1132 0.97 1194 1.09

937 0.69 1006 0.80

947 0.74 1015 0.86 1079 0.98 1141 1.10 1201 1.23

959 0.81 1025 0.93 1088 1.05 1148 1.18 1207 1.31

973 0.88 1037 1.00 1098 1.13 1157 1.26 1214 1.39

988 0.95 1050 1.08 1110 1.21 1168 1.35 1223 1.48
1004 1.04 1065 1.17 1123 1.30 1179 1.44 1234 1.58

__ High--Range Motor/Drive Required

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

1072 0.91 1136 1.03 1196 1.16

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

941 0.91

Table 51 — Fan Performance -- 48PDE05 Horizontal Units

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

LEGEND
Bhp -- Brake Horsepower

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

443 0.12 564 0.20 666 0.27 758 0.36 842 0.45

463 0.15 580 0.22 678 0.31 767 0.40 849 0.49

485 0.17 598 0.26 693 0.34 778 0.44 858 0.54

508 0.21 617 0.30 709 0.39 792 0.48 869 0.59

532 0.24 638 0.34 727 0.43 807 0.54 882 0.64

558 0.28 660 0.39 746 0.49 824 0.59 896 0.70

584 0.33 682 0.44 766 0.55 842 0.66 912 0.77

611 0.38 706 0.50 788 0.61 861 0.72 930 0.84

639 0.44 731 0.56 810 0.68 882 0.80

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

922 0.55 996 0.65 1066 0.75 1133 0.86 1196 0.97

926 0.59 999 0.69 1068 0.80 1133 0.92 1196 1.03

933 0.64 1004 0.75

942 0.69 1011 0.80 1077 0.92 1140 1.04 1200 1.17

952 0.75 1020 0.87 1084 0.99 1146 1.11 1205 1.24

965 0.82 1030 0.94 1093 1.06 1153 1.19 1211 1.32

979 0.89 1043 1.01 1104 1.14 1163 1.27 1220 1.41

995 0.97 1057 1.09 1116 1.22 1174 1.36 1229 1.50
1012 1.05 1072 1.18 1130 1.32 1186 1.46 1240 1.60

__ High--Range Motor/Drive Required

0.2 0.4 0.6 0.8 1.0

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

1071 0.86 1136 0.98 1197 1.10

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

948 0.92

94

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

Table 52 — Fan Performance - 48PDF05 Horizontal Units

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

456 0.13 574 0.20 675 0.28 766 0.37 850 0.46

477 0.16 591 0.23 688 0.32 776 0.41 857 0.50

500 0.18 610 0.27 703 0.36 788 0.45 867 0.55

524 0.22 630 0.31 720 0.40 802 0.50 879 0.60

550 0.26 652 0.35 739 0.45 819 0.55 893 0.66

576 0.30 675 0.40 759 0.50 836 0.61 908 0.72

604 0.35 699 0.46 781 0.57 856 0.68 925 0.79

633 0.41 724 0.52 804 0.63 876 0.75

662 0.47 750 0.59 828 0.71 898 0.83 964 0.95

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

944 0.87

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

LEGEND
Bhp -- Brake Horsepower

High Range Motor/Drive Required

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

929 0.56 1003 0.66 1073 0.76 1139 0.87 1202 0.98

934 0.60 1006 0.71 1075 0.82 1140 0.93 1202 1.05

941 0.65 1012 0.76

1079 0.87 1143 0.99 1204 1.11

951 0.71 1020 0.82 1085 0.94 1148 1.06 1208 1.18

963 0.77 1029 0.89 1093 1.01 1155 1.13 1214 1.26

976 0.84 1041 0.96 1103 1.08 1163 1.21 1221 1.34

991 0.91 1054 1.04 1115 1.16 1174 1.30 1230 1.43
1008 0.99 1070 1.12 1129 1.25 1186 1.39 1241 1.53
1026 1.08 1086 1.21 1144 1.35 1199 1.49

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

1253 1.63

Table 53 — Fan Performance - 48PDD06 Horizontal Units

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

521 0.22 628 0.31 718 0.40  800 0.49 877 0.60

546 0.25 649 0.35 737 0.45  816 0.55 890 0.65

572 0.30 671 0.40 757 0.50  834 0.61 906 0.72

599 0.35 695 0.45 777 0.56  852 0.67 922 0.79

627 0.40 719 0.51 799 0.63  872 0.74 940 0.86

655 0.46 745 0.58 822 0.70  893 0.82 959 0.94

684 0.53 771 0.66 846 0.78  915 0.91 979 1.03

714 0.61 797 0.74 871 0.87  938 1.00 1001 1.13

744 0.69 824 0.83 896 0.96  961 1.10 1022 1.24

775 0.78 852 0.92 922 1.06  985 1.21 1045 1.35

806 0.88 880 1.03 948 1.18 1010 1.32 1069 1.47

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

48/50PD

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

949 0.70 1018 0.82 1083 0.93 1146 1.05 1207 1.18

961 0.77 1027 0.88 1091 1.00 1153 1.13 1212 1.26

974 0.83 1039 0.95 1101 1.08 1161 1.21 1219 1.34

988 0.91 1052 1.03 1112 1.16 1171 1.29 1227 1.43

1004 0.99 1066 1.11 1125 1.25 1182 1.38 1238 1.52
1022 1.07 1082 1.20 1139 1.34 1195 1.48 1249 1.62
1040 1.17 1099 1.30 1155 1.44 1209 1.59 1262 1.73
1060 1.27 1117 1.41 1172 1.55 1225 1.70 1277 1.85
1081 1.38 1136 1.52 1190 1.67 1242 1.82 1292 1.98
1102 1.50 1156 1.65 1209 1.80 1259 1.96 1309 2.12
1124 1.62 1177 1.78 1228 1.94 1278 2.10 1326 2.26

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

95

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

Table 54 — Fan Performance - 48PDE06 Horizontal Units

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

536 0.23 640 0.32 729 0.41 811 0.51 887 0.61
563 0.27 663 0.36 749 0.46 828 0.56 901 0.67
590 0.31 686 0.42 770 0.52 846 0.62 917 0.74
619 0.37 711 0.47 792 0.58 866 0.69 935 0.81
648 0.43 737 0.54 816 0.65 887 0.77 954 0.89
678 0.49 764 0.61 840 0.73 909 0.85 975 0.98
709 0.56 792 0.69 865 0.81 933 0.94 996 1.07
740 0.65 820 0.78 891 0.91 957 1.04 1019 1.17
772 0.73 849 0.87 918 1.01 982 1.14 1042 1.28
804 0.83 879 0.97 946 1.12 1008 1.26 1066 1.40
837 0.94 909 1.09 974 1.24 1034 1.38 1092 1.53

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000

48/50PD

2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

958 0.72 1027 0.83 1092 0.95 1154 1.07 1214 1.20
971 0.78 1037 0.90 1101 1.02 1162 1.15 1221 1.28

985 0.85 1049 0.97 1111 1.10 1171 1.23 1228 1.36
1001 0.93 1063 1.05 1124 1.18 1182 1.32 1238 1.45
1018 1.01 1079 1.14 1138 1.27 1194 1.41 1249 1.55
1036 1.10 1096 1.24 1153 1.37 1208 1.51 1262 1.66
1056 1.20 1114 1.34 1170 1.48 1224 1.63 1276 1.78
1077 1.31 1134 1.45 1188 1.60 1241 1.75 1292 1.90
1099 1.43 1154 1.57 1207 1.72 1259 1.88 1309 2.03
1122 1.55 1176 1.70 1228 1.86 1278 2.02 1327 2.18
1146 1.69 1198 1.84 1249 2.00 1298 2.16 1346 2.33

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

Table 55 — Fan Performance - 48PDF06 Horizontal Units

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

551 0.24 653 0.33 741 0.42 821 0.52 896 0.62

579 0.28 676 0.38 761 0.48 839 0.58 912 0.69

608 0.33 701 0.43 783 0.54 858 0.64 929 0.76

638 0.39 727 0.49 807 0.60 879 0.71 948 0.83

668 0.45 755 0.56 831 0.68 902 0.79 968 0.91

700 0.52 783 0.64 857 0.76 925 0.88 990 1.01

732 0.60 812 0.72 884 0.85 950 0.97 1013 1.11

765 0.68 842 0.81 912 0.95 976 1.08 1037 1.21

799 0.78 873 0.92 940 1.05 1002 1.19 1062 1.33

833 0.88 904 1.03 969 1.17 1030 1.31 1087 1.46

867 1.00 936 1.15 999 1.30 1058 1.44 1114 1.60

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

968 0.73 1035 0.85 1100 0.97 1162 1.09 1222 1.21

981 0.80 1047 0.92 1110 1.04 1171 1.16 1229 1.29

996 0.87 1060 0.99 1121 1.12 1181 1.25 1238 1.38
1013 0.95 1075 1.08 1135 1.21 1193 1.34 1248 1.48
1031 1.04 1092 1.17 1150 1.30 1206 1.44 1261 1.58
1051 1.14 1110 1.27 1166 1.41 1221 1.55 1275 1.69
1072 1.24 1129 1.38 1185 1.52 1238 1.67 1290 1.82
1094 1.35 1150 1.50 1204 1.64 1256 1.79 1307 1.95
1118 1.48 1172 1.62 1225 1.77 1275 1.93 1325 2.09
1142 1.61 1195 1.76 1246 1.92 1296 2.07 1344 2.24
1168 1.75 1219 1.91 1269 2.07 1317 2.23 1365 2.40

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

96

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

Table 56 — Fan Performance - 50PD05 Vertical Units

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

492 0.15 604 0.22 701 0.31 790 0.39 873 0.49
513 0.18 620 0.26 714 0.34 800 0.43 880 0.53
534 0.21 638 0.29 729 0.38 812 0.48 889 0.58
557 0.24 657 0.33 745 0.43 825 0.53 900 0.63
580 0.28 677 0.38 762 0.48 839 0.58 912 0.69
603 0.33 697 0.43 779 0.53 855 0.64 926 0.75
627 0.38 718 0.48 798 0.59 871 0.70 940 0.82
651 0.43 739 0.54 817 0.65 889 0.77 956 0.89
675 0.49 761 0.61 837 0.72 907 0.85 972 0.97

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

LEGEND
Bhp -- Brake Horsepower

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

950 0.58 1023 0.69 1092 0.79 1157 0.90 1219 1.02
955 0.63 1027 0.74 1094 0.85 1158 0.96 1220 1.08
962 0.68 1032 0.79 1098 0.91 1161 1.03 1222 1.15
971 0.74 1039 0.85 1103 0.97 1165 1.09 1225 1.22
981 0.80 1047 0.92 1110 1.04 1171 1.17 1229 1.30

993 0.87 1057 0.99 1118 1.11 1178 1.24 1235 1.38
1005 0.94 1068 1.06 1128 1.19 1186 1.33 1242 1.46
1019 1.02 1080 1.14 1139 1.28 1196 1.41 1251 1.56
1034 1.10 1094 1.23 1151 1.37 1206 1.51 1260 1.65

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

Table 57 — Fan Performance -- 50PD06 Vertical Units

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

568 0.25 667 0.34 753 0.44 833 0.54 908 0.64
592 0.29 687 0.39 771 0.49 848 0.59 920 0.70
616 0.34 708 0.44 789 0.54 864 0.65 934 0.76
641 0.39 730 0.50 809 0.61 881 0.72 950 0.83
665 0.45 752 0.56 829 0.67 900 0.79 966 0.91
690 0.51 775 0.63 850 0.75 918 0.87 983 0.99
716 0.57 798 0.70 871 0.82 938 0.95 1001 1.08
742 0.65 821 0.78 892 0.91 958 1.04 1020 1.18
768 0.73 845 0.86 915 1.00 979 1.14 1039 1.28
794 0.81 869 0.96 937 1.10 1000 1.24 1059 1.38
820 0.91 894 1.05 960 1.20 1021 1.35 1079 1.50

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

48/50PD

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

1.2 1.4 1.6 1.8 2.0

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

978 0.75 1046 0.87 1110 0.98 1172 1.11 1231 1.23

989 0.81 1055 0.93 1117 1.05 1178 1.18 1236 1.31
1001 0.88 1065 1.00 1126 1.13 1185 1.26 1242 1.39
1015 0.96 1077 1.08 1136 1.21 1194 1.35 1250 1.48
1029 1.04 1090 1.16 1148 1.30 1204 1.44 1259 1.58
1045 1.12 1104 1.26 1161 1.39 1216 1.53 1269 1.68
1061 1.21 1119 1.35 1174 1.49 1228 1.64 1280 1.79
1078 1.31 1135 1.45 1189 1.60 1241 1.75 1293 1.90
1096 1.42 1151 1.57 1204 1.71 1256 1.87 1306 2.02
1115 1.53 1169 1.68 1221 1.84 1271 1.99 1320 2.15
1134 1.65 1187 1.81 1238 1.97 1287 2.13 1335 2.29

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

97

Table 58 — Fan Performance - 50PD05 Horizontal Units

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900
2000

AIRFLOW

(Cfm)

1200
1300
1400
1500
1600
1700
1800
1900

48/50PD

2000

LEGEND
Bhp -- Brake Horsepower

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

422 0.11 548 0.19 652 0.26 745 0.35 831 0.44
439 0.13 561 0.21 662 0.29 752 0.38 835 0.47
457 0.16 577 0.24 674 0.33 761 0.42 842 0.51
477 0.19 593 0.27 688 0.37 773 0.46 851 0.56
498 0.22 611 0.31 704 0.41 786 0.51 862 0.61
521 0.25 630 0.35 720 0.46 801 0.56 875 0.67
545 0.29 650 0.40 738 0.51 817 0.62 889 0.73
569 0.34 672 0.45 757 0.57 834 0.68 904 0.80
595 0.39 694 0.51 777 0.63 852 0.75

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

911 0.53  986 0.63 1056 0.74 1123 0.85 1187 0.96
913 0.57  986 0.68 1056 0.78 1122 0.90 1185 1.01
918 0.62  989 0.72 1058 0.84 1123 0.95 1185 1.07
925 0.67  995 0.78 1061 0.89 1125 1.01 1186 1.14
934 0.72 1002 0.84 1067 0.95 1129 1.08 1189 1.21
944 0.78 1010 0.90 1074 1.02 1135 1.15 1194 1.28
956 0.85 1021 0.97 1083 1.09 1143 1.23 1200 1.36
970 0.92 1033 1.04 1094 1.17 1152 1.31 1208 1.45
985 1.00 1047 1.13 1106 1.26 1162 1.40 1217 1.54

__High Range Motor/Drive Required

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

921 0.87

Table 59 — Fan Performance -- 50PD06 Horizontal Units

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

491 0.19 604 0.28 697 0.37 781 0.47 859 0.57
513 0.23 623 0.32 714 0.42 795 0.52 871 0.62
537 0.27 643 0.37 731 0.47 810 0.57 884 0.68
561 0.31 664 0.42 750 0.52 827 0.63 899 0.75
586 0.36 686 0.47 770 0.58 845 0.70 915 0.82
613 0.41 709 0.53 790 0.65 864 0.77
640 0.47 732 0.60 812 0.72 884 0.85 950 0.97
667 0.54 757 0.67 834 0.80
695 0.61 782 0.75 857 0.89 926 1.02 989 1.16
724 0.69 807 0.84 881 0.98 948 1.12 1010 1.26
753 0.78 833 0.93 905 1.08 971 1.23 1032 1.38

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

932 0.89

904 0.93 969 1.06

AIRFLOW

(Cfm)

1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500

LEGEND
Bhp -- Brake Horsepower

Low Range Motor/Drive Required

1.2 1.4 1.6 1.8 2.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

932 0.68 1002 0.79 1068 0.91 1132 1.03 1192 1.15
942 0.73 1009 0.85 1074 0.97 1136 1.09 1196 1.22
953 0.80
966 0.86 1030 0.99 1092 1.11 1151 1.24 1208 1.38
980 0.94 1043 1.06 1103 1.19 1161 1.33 1217 1.47

996 1.02 1057 1.15 1115 1.28 1172 1.42 1227 1.56
1012 1.11 1072 1.24 1129 1.38 1184 1.52 1238 1.67
1030 1.20 1088 1.34 1144 1.48 1198 1.63 1251 1.78
1049 1.30 1106 1.44 1160 1.59 1213 1.74 1265 1.89
1068 1.41 1124 1.56 1178 1.71 1229 1.86 1279 2.02
1089 1.53 1143 1.68 1196 1.84 1246 1.99 1295 2.16

1019 0.91 1082 1.04 1143 1.17 1201 1.30

AVAILABLEEXTERNALSTATICPRESSURE(in.wg)

NOTES:

1. Maximum continuous BHP is 2.0.

2. See General Fan Performance Notes.

98

GENERAL NOTES FOR FAN PERFORMANCE DATA TABLES

1. Static pressure losses from accessories and options
(economizer, etc.) must be added to external static pressure
before entering Fan Performance table. Refer to
Accessory/FIOP Static Pressure information.

2. Interpolation is permissible. Do not extrapolate.

3. Fan performance tables are based on wet coils, clean filters,
and casing losses. Gas heat losses are included for 48 series
units.

4. Extensive motor and drive testing on these units ensures
that the full horsepower range of the motor can be utilized
with confidence. Using the fan motors up to the bhp rating
shown will not result in nuisance tripping or premature
motor failure. Unit warranty will not be affected.

5. Use of a field-supplied motor may affect wire size.
Recalculate the unit power supply MCA and MOCP if
required. Contact your Carrier representative for details.

6. Use the following formula to calculate input watts:
Input Watts = Bhp x (746/Motor Eff)

48/50PD

99

APPENDIX D -- ADDITIONAL START--UP DATA

Table 60 — Air Quantity Limits (50PD Units)

UNIT

50PD

05
06

COOLING (cfm)

1200 2000 1200 2000
1500 2500 1500 2500

HEATING (cfm)

OPTIONAL ELECTRIC HEAT

Table 61 — Air Quantity Limits (48PD Units)

UNIT

48PD

05 (Low Heat)

05 (Med Heat)

05 (High Heat)

06 (Low Heat)

06 (Med Heat)

06 (High Heat)

COOLING (cfm) HEATING (cfm)

Min Max Min Max

1200 2000 600 1680
1200 2000 940 2810
1200 2000 1130 2820
1500 2500 940 2810
1500 2500 1130 2820
1500 2500 1510 2520

Table 62 — Evaporator Fan Motor Specifications - 48/50PD

48/50PD DRIVE VOLTAGE/PHASE EFFICIENCY MAX BHP MAX AMPS

05 & 06 Low & High

NOTES:

1. Extensive motor and electrical testing ensures that the motors can be utilized
with confidence up to the maximum applied bhp, watts, and amps. Using the fan
motor up to the maximum ratings shown will not result in nuisance tripping or
premature motor failure. Unit warranty will not be affected.

2. Convert bhp to watts using the following formula:

48/50PD

watts =

bhp (746)

motor efficiency

208/230--- 3ph 0.80 2.0 6.4

460--- 3ph 0.80 2.0 3.2

3. The EPACT (Energy Policy Act of 1992) regulates energy requirements for
specific types of indoor-fan motors. Motors regulated by EPACT include any
general purpose, T-frame (three-digit, 143 and larger), single-speed, foot
mounted, polyphase, squirrel cage induction motors of NEMA (National Electrical
Manufacturers Association) design A and B, manufactured for use in the United
States. Ranging from 1 to 200 Hp, these continuous-duty motors operate on 230
and 460 volt, 60 Hz power. If a motor does not fit into these specifications, the
motor does not have to be replaced by an EPACT-compliant energy- efficient motor.
Variable-speed mo tors are exempt from EPACT compliance requirements.
Therefore, the indoor-fan motors for Carrier 48/50PG03--14 units are exempt from
these requirements.

Table 63 — Fan Rpm at Motor Pulley Settings* - 48/50PD

UNIT

48/50PD

05

06

*Approximate fan rpm shown, based on 1725 rpm motor.

NOTE: Factory speed setting is at 5 turns open.

DRIVE

0

1

/

Low 910 878 847 815 784 753 721 690 659 627 596

High 1173 1139 1104 1070 1035 1001 966 932 897 863 828

Low 978 949 920 891 863 834 805 776 748 719 690

High 1261 1227 1194 1161 1128 1095 1062 1028 995 962 929

2

1 11/

MOTOR PULLEY TURNS OPEN

2

2 21/

2

3 31/

2

4 41/

2

5

AIRFLOW

(CFM)

600

800
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000

Table 64 — Accessory/FIOP Pressure Drop (in. wg) - 48/50PD

ELECTRIC

HEAT

0.01 0.01 0.03

0.01 0.01 0.05

0.02 0.02 0.07

0.02 0.03 0.10

0.03 0.04 0.14

0.04 0.06 0.17

0.05 0.07 0.22

0.07 0.09 0.26

0.08 0.11 0.31

0.10 0.13 0.37

0.11 0.15 0.43

0.13 0.18 0.49

0.15 0.21 0.56

ECONOMIZER

(Vertical)

ECONOMIZER

(Horizontal)

100