Sterling 30RA010-055 User Manual

Controls, Start-Up, Operation,

Service, and Troubleshooting

SAFETY CONSIDERATIONS

Installing, starting up, and servicing this equipment can be
hazardous due to system pressures, electrical components, and
equipment location (roof, elevated structures, mechanical
rooms, etc.). Only trained, qualified installers and service
mechanics should install, start up, and service this equipment.

When working on this equipment, observe precautions in
the literature, and on tags, stickers, a nd labels attached to the
equipment, and any other safety precautions that apply. Follow
all safety codes. Wear safety glasses and work gloves. Use
care in handling, rigging, and setting this equipment, and in
handling all electrical components.

Electrical shock can cause personal injury and death. Shut
off all power to this equipment during installation and
service. There may be more than one disconnect switch.
Tag all disconnect locations to alert others not to restore
power until work is completed.

DO NOT VENT refrigerant relief valves within a building.
Outlet from relief valves must be vented outdoors in
accordance with the latest edition of ANSI/ASHRAE
(American National Standards Institute/Ame rican Society
of Heating, Refrigeration and Air Conditioning Engineers)
15 (Safety Code for Mechanical Refrigeration). The
accumulation of refrigerant in an enclosed space can
displace oxygen and cause asphyxiation. Provide adequate
ventilation in enclosed or low overhead areas. Inhalation of
high concentrations of vapor is harmful and may cause
heart irregularities, unconsciousness or death. Misuse can
be fatal. Vapor is heavier than air and reduces the amount
of oxygen available for breathing. Product causes eye and
skin irritation. Decomposition products are hazardous.

30RA010-055

AquaSnap® Air-Cooled Chillers

with ComfortLink™ Controls

50/60 Hz

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.

To prevent potential damage to heat exchanger, always run
fluid through heat exchanger when adding or removing
refrigerant charge. Use appropriate brine solutions in cooler
fluid loop to prevent the freezing of brazed plate heat
exchanger, option al hydronic section and/or interconnecting
piping when the equipment is exposed to temperatures
below 32 F (0 °C). Proof of flow switch and strainer are
factory installed on all models. Do NOT remove power
from this chiller during winter shutdown periods without
taking precaution to remove all water from heat exchanger
and optional hydronic system. Failure to properly protect
the system from freezing may constitute abuse and may
void warranty.

Compressors and optional hydronic system pumps require
specific rotation. Test condenser fan(s) first to ensure
proper phasing. Swap any two incoming power leads to
correct condenser fan rotation before starting any other
motors.

Refrigerant charge must be removed slowly to prevent loss

DO NOT attempt to unbraze factory joints w hen servicing
this equipment. Compressor oil is flammable and there is
no way to detect how much oil may be in any of the
refrigerant lines. Cut lines with a tubing cutter as re quired
when performing service. Use a pan to catch any oil that
may come out of the lines and as a gage for how much oil
to add to system. DO NOT re-use compressor oil.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 2
Ta b 5 c

PC 903 Catalog No. 533-00047 Printed in U.S.A. Form 30RA-2T Pg 1 1-03 Replaces: 30RA-1T

of compressor oil that could result in compressor failure.

CONTENTS

Page

SAFETY CONSIDERATIONS
GENERAL
MAJOR SYSTEM COMPONENTS

General
Main Base Board (MBB)
Scrolling Marquee Display
Energy Management Module (EMM)
Enable/Off/Remote Contact Switch
Emergency On/Off Switch
Board Addresses
Control Module Communication
Sterlco Comfort Network Interface
OPERATING DATA
Sensors

• T1 — COOLER LEAVING FLUID SENSOR

• T2 — COOLER ENTERING FLUID SENSOR

• T7,T8 — COMPRESSOR RETURN GAS
TEMPERATURE SENSOR (ACCESSORY)

• T9 — OUTDOOR-AIR TEMPERA TURE SENSOR

• T10 — REMOTE SPACE TEMPERATURE SENSOR OR
DUAL LEAVING WATER TEMPERATURE SENSOR

Energy Management Module
Loss-of-Cooler Flow Protection
Thermostatic Expansion Valves (TXV)
Capacity Control

• MINUTES LEFT FOR START

• MINUTES OFF TIME

• LEAD/LAG DETERMINATION

• CAPACITY CONTROL OVERRIDES

Head Pressure Control
Operation of Machine Based on Control Method

and Cooling Set Point Selection Settings
Cooling Set Point Select
Marquee Display Usage
Service Test
Optional Factory-Installed Hydronic Package
Cooler Pump Control
Cooler Pump Sequence of Operation
Configuring and Operating Dual Chiller Control
Temperature Reset
Demand Limit

• DEMAND LIMIT (2-Stage Switch Controlled)

• EXTERNALLY POWERED DEMAND LIMIT

(4 to 20 mA Controlled)

• DEMAND LIMIT (SCN Loadshed Controlled)

Cooling Set Point (4 to 20 mA)
TROUBLESHOOTING
Complete Unit Stoppage and Restart

• GENERAL POWER FAILURE

• UNIT ENABLE-OFF-REMOTE CONTACT SWITCH IS

OFF

• CHILLED FLUID PROOF-OF-FLOW SWITCH OPEN

• OPEN HIGH-PRESSURE SWITCH(ES)

• OPEN COMPRESSOR INTERNAL THERMAL

PROTECTION

• OPEN 24-V CONTROL CIRCUIT BREAKERS

• COOLING LOAD SATISFIED

• THERMISTOR FAILURE

• LOW SATURATED SUCTION

Alarms and Alerts
SERVICE
Electronic Components

• CONTROL COMPONENTS

Compressor Replacement
Cooler

• BRAZED-PLATE COOLER HEAT EXCHANGER

REPLACEMENT

• BRAZED-PLATE COOLER HEAT EXCHANGER

CLEANING

Check Oil Charge

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Page

Condenser Section and Coils

• COIL CLEANING

• CLEANING E-COATED COILS

• CONDENSER SECTION

Check Refrigerant Feed Components

• THERMOSTATIC EXPANSION VALVE (TXV)

•FILTER DRIER

• MOISTURE-LIQUID INDICATOR

• MINIMUM LOAD VALVE

• PRESSURE RELIEF DEVICES

Compressor and Unit Protective Devices

• MANUAL STARTER

• COMPRESSOR INTERNAL THERMAL PROTECTION

Check Unit Safeties

• HIGH-PRESSURE SWITCH

• PRESSURE TRANSDUCERS

• COOLER FREEZE-UP PROTECTION

• HEATER CABLE

• WINTER SHUTDOWN

Thermistors
Pressure Transducers
Flow Sensor
Strainer
Motormaster® V Controller

• GENERAL OPERATION

• SET POINTS

•INSTALLATION

• PROGRAMMING

•EPM CHIP

• LIQUID LINE PRESSURE SET POINT ADJUSTMENT

• LOSS OF SCN COMMUNICATIONS

• REPLACING DEFECTIVE MODULES

Hydronic Package
MAINTENANCE

Recommended Maintenance Schedule
PRE-START-UP
System Check
START-UP AND OPERATION
Actual Start-Up
Check Refrigerant Charge
Operating Limitations

• TEMPERATURES

• LOW AMBIENT OPERATION

• VOLTAGE — ALL UNITS

OPERATION SEQUENCE
APPENDIX A — SCN TABLES
APPENDIX B — FACTORY SETTINGS FOR

COMPRESSOR, FAN, PUMP AND MANUAL

STARTERS
APPENDIX C — BUILDING INTERFACE
START-UP CHECKLIST FOR 30RA LIQUID

CHILLER

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GENERAL

This publication contains Controls Start-Up, Service, Oper­ation, and Troubleshooting information for the 30RA
AquaSnap® air-cooled chillers. Se e Table 1. These chillers are
equipped with ComfortLink™ controls and conventional
thermostatic expansion valves (TXVs).

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

2

Table 1 — Unit Sizes

NOMINAL CAPACITY

(TONS) 50/60 Hz

10/10
14/13
16/16
22/20
24/23

27
30

35/34

38
40

43/45

47
54

*60 Hz only.

†50 Hz only.

UNIT

30RA010

30RA015

30RA018

30RA022

30RA025

30RA030*

30RA032†

30RA035

30RA040*

30RA042†

30RA045

30RA050*

30RA055*

MAJOR SYSTEM COMPONENTS

General —

contain the ComfortLink™ electronic control system that
controls and monitors all operations of the chiller.

The control system is composed of several components as
listed in the sections below. See Fig. 1 and 2 for typical control
box drawing. See Fig. 3-6 for control schematics.

Main Base Board (MBB) —

the heart of the ComfortLink control system. It contains the
major portion of operating software and controls the ope ration
of the machine. The MBB continuously monitors input/output
channel information received from its inputs and from all other
modules. The MBB receives inputs from the discharge and
suction pressure transducers and thermistors. See Table 2. The
MBB also receives the feedback inputs from each compressor
contactor, auxiliary contacts, and other status switches. See
T a ble 3. The MBB also controls several outputs. Relay outputs
controlled by the MBB are shown in Table 4. Information
is transmitted between modules via a 3-wire communication
bus or LEN (Local Equipment Network). The SCN (Sterlco
Comfort Network) bus is also supported. Connections to both
LEN and SCN buses are made at TB3. See Fig. 8.

Scrolling Marquee Display —

is the keypad interface used for accessing chiller information,
reading sensor values, and testing the chiller. The marquee
display is a 4-key, 4-character , 16-segment LED (light-emitting
diode) display. Eleven mode LEDs are loca ted on the display
as well as an Alarm Status LED. See Marquee Display Usa ge
section on page 23 for further details.

Energy Management Module (EMM) —

module is available as a factory-installed option or as a field­installed accessory. The EMM module receives 4 to 20 mA
inputs for the leaving fluid temperature reset, cooling set point
and demand limit functions. The EMM module also receives
the switch inputs for the field-installed 2-stage demand limit
and ice done functions. The EMM module communicates the
status of all inputs with the MBB, and the MBB adjusts the
control point, capacity limit, and other functions according to
the inputs received.

Enable/Off/Remote Contact Switch —

Off/Remote Contact switch is a 3-position switch used to
control the chiller. When switched to the Enable position the
chiller is under its own control. Move the switch to the Off
position to shut the chiller down. Move the switch to the
Remote Contact position and a field-installed dry contact can
be used to start the chiller. The contacts must be capable of
handling a 24 vac, 50-mA load. In the Enable and Remote

The 30RA air-cooled reciprocating chillers

See Fig. 7. The MBB is

This standard device

The EMM

The Enable/

Contact (dry contacts closed) positions, the chiller is allowed to
operate and respond to the scheduling configuration, SCN
configuration and set point data. See Fig. 8.

Emergency On/Off Switch —

The Emergency On/Off
switch should only be used when it is required to shut the
chiller off immediately. Power to the MBB, EMM, and
marquee display is interrupted when this switch is off and all
outputs from these modules will be turned off.

Board Addresses —

The Main Base Board (MBB) has
a 3-position Instance jumper that must be set to ‘1.’ All other
boards have 4-position DIP switches. All switches are set to
‘On’ for all boards.

Control Module Communication

RED LED — Proper operation of the control boards can be
visually checked by looking at the red status LEDs
(light-emitting diodes). When operating correctly, the red status
LEDs should be blinking in unison at a rate of once every
2 seconds. If the red LEDs are not blinking in unison, verify
that correct power is being supplied to all modules. Be sure that
the Main Base Board (MBB) is supplied with the current
software. If necessary, reload current software. If the problem
still persists, replace the MBB. A red LED that is lit continu­ously or blinking at a rate of once per second or faster indicates
that the board should be replaced.

GREE N LED — The MBB has one green LED. The Local
Equipment Network (LEN) LED should always be blinking
whenever power is on. All other boards have a LEN LED
which should be blinking whenever power is on. Check LEN
connections for potential communication errors at the board J3
and/or J4 connectors. 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
provides both power and communication directly to the
marquee display only.

YELLOW LED — The MBB has one yellow LED. The
Sterlco Comfort Network (SCN) LED will blink during times
of network communication.

Sterlco Comfort Network (SCN) Interface —

The 30RA chiller units can be connected to the SCN if
desired. The communication bus wiring is a shielded,
3-conductor cable with drain wire and is supplied and installed
in the field. See Table 5. The system elements are connected to
the communication bus in a daisy chain arrangement. 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 SCN should be made at TB3. Consult the SCN Contrac­tor’s Manual for further information.

NOTE: Conductors and drain wire must be 20 AWG (Ameri­can Wire Gage) 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 C to 60 C is required. Wire manufactured by Alpha (2413
or 5463), American (A22503), Belden (8772), or Columbia
(02525) meets the above mentioned requirements.

It is important when connecting to a SCN 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.

3

At each system element, the shields of its communication
bus cables must be tied together. If the communication bus is
entirely within one building, the resulting continuous shield
must be connected to a ground at one point only. If the commu­nication bus cable exits from one building and enters another,
the shields must be connected to grounds at the lightning
suppressor in each building 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 SCN wire and strip the ends of the red (+), white
(ground), and black (–) conductors. (Substitute appropri­ate colors for different colored cables.)

3. Connect the red wire to (+) terminal on TB3 of the plug,
the white wire to COM terminal, and the black wire to the
(–) terminal.

4. The RJ14 SCN connector on TB3 can also be used, but is
only intended for temporary connection (for example, a
laptop computer running Service Tool).

Table 4 — Output Relays

RELAY

NO.

Energize Compressor A1 (010-030)

K1

Energize Compressor A1 and Condenser Fan A1 (032-055)
Energize Compressor B1 and Condenser Fan B1 at Low

Speed (032-040)

K2

Energize Compressor B1 and Condenser Fan B1 (042-055)

K3 Energize Chilled Water Pump 1 Output
K4 Energize Chilled Water Pump 2 Output
K5 Energize Compressor A2 (all but 010, 015 60Hz)
K6 Energize Compressor B2 (042-055 only)
K7 Alarm Relay
K8 Cooler/Pump Heater

Energize Condenser Fan at Low Speed (010-018)
Energize Condenser Fan A1 (022-030)

K9

Energize Condenser Fan A2 (032-055)
Energize Condenser Fan at High Speed (010-018)

Energize Condenser Fan A2 (022-030)

K10

Energize Condenser Fan B1 at High Speed (032-040)
Energize Condenser Fan B2 (042-055)

K11 Minimum Load Valve

DESCRIPTION

IMPORTANT: A shorted SCN 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 SCN connector and
cable. Run new cable if necessary. A short in on e section of
the bus can cause problems with all system elements on the
bus.

Table 2 — Thermistor Designations

THERMISTOR

NO.

T1 J8-13,14 (MBB) Cooler Leaving Fluid
T2 J8-11,12 (MBB) Cooler Entering Fluid

T7

T8

T9

T10

LW T — Leaving Water Temperature
MBB — Main Base Board

LEGEND

PIN

CONNECTION

POINT

J8-1,2 (MBB) Circuit A Return Gas

J8-3,4 (MBB) Circuit B (032-055 only) Return

J8-7,8 (MBB) Outdoor-Air Temperature

J8-5,6 (MBB)
TB5-5,6

THERMISTOR INPUT

Temperature (Accessor y)

Gas Temperature (Accessory)

Sensor
Accessory Remote Space

Temperature Sensor or
Dual LWT Sensor

Table 3 — Status Switches

STATUS

SWITCH
Chilled Water Pump 1 J7-1,2
Chilled Water Pump 2 J7-3,4

Remote On/Off TB5-9,10

Cooler Flow Switch J7-9,10
Compressor Fault Signal, A1 J9-11,12
Compressor Fault Signal, A2 J9-5,6
Compressor Fault Signal, B1 J9-8,9
Compressor Fault Signal, B2 J9-2,3

PIN CONNECTION

POINT

Table 5 — SCN Communication Bus Wiring

MANUFACTURER

Alpha 1895 —
American A21451 A48301
Belden 8205 884421
Columbia D6451 —
Manhattan M13402 M64430
Quabik 6130 —

Regular Wiring Plenum Wiring

PART NO .

OPERATING DATA

Sensors —

The electronic control uses 3 to 6 thermistors to
sense temperatures for controlling chiller operation. See
T able 2. These sensors are outlined below. Thermistors T1, T2,
T9 and accessory suction gas temperatures (T7,T8) are 5 kΩ at
77 F (25 C) and are identical in temperature versus resistance
and voltage drop performance. Thermistor T10 is 10 kΩ at
77 F (25 C) and has a different temperature vs. resistance and
voltage drop performance. See Thermistors section for
temperature-resistance-voltage drop characteristics.

T1 — CO OL ER L EAVIN G FL UID SE NSO R — On 30RA010­030 sizes, this thermistor is installed in a friction fit well at the
bottom of the brazed-plate heat exchanger on the cont rol box
side. For 30RA032-055 sizes, this thermistor is installed in a
well in the factory-installed leaving fluid piping coming from
the bottom of the brazed-plate heat exchanger opposite the
control box side.

T2 — C OO L E R E NT E RI N G F L UI D SE N SO R — On 30RA010­030 sizes, this thermistor is installed in a friction fit well at the
top of the brazed-plate heat exchanger on the control box side.
For 30RA032-055 sizes, this thermistor is installed in a well in
the factory-installed entering fluid piping coming from t he top
of the brazed-plate heat exchanger opposite the control box
side.

T7,T8 — COMPRESSOR RETURN GAS TEMPERA­TURE SENSOR (ACCESSORY) — A well for this sensor
is factory installed in each circuit's suction line. If desired, a
5 kΩ thermistor (Sterling part number HH79NZ029) can be
installed in this well and connected to the Main Base Board
as shown in Tabl e 2. Use the Scrolling Marquee display to con­figure the sensor (Configuration mode, sub-mode OPT1 —
enable item RG.EN).

T9 — OUTDOOR-AIR TEMPERATURE SENSOR —
This sensor is factory-installed on a bracket at the left side of
compressor A1 on 30RA010-030 models. For models
30RA032-055, it is installed behind the panel below the
control box center door.

4

T10 — REMOTE SPACE TEMPERATURE SENSOR OR
DUAL LEAVING WATER TEMPERATURE SENSOR —

One of two inputs can be connected to TB5-5 and TB5-6. See
appropriate sensor below.

T10 — Remote Space Temperature Sensor

— Sensor T10
(part no. 33ZCT55SPT) is an accessory sensor that is remotely
mounted in the controlled space and used for space tempera­ture reset. The sensor should be installed as a wall-mount ed
thermostat would be (in the conditioned space where it will not
be subjected to either a cooling or heating source or direct
exposure to sunlight, and 4 to 5 ft above the floor).

Space temperature sensor wires are to be connected to
terminals in the unit main control box. T he space temperature
sensor includes a terminal block (SEN) and a RJ11 female
connector. The RJ11 connector is used access into the Sterlco
Comfort Network (SCN) at the sensor.

T o connect the space temperature sensor (Fig. 9):

1. Using a 20 AWG twisted pair conductor cable rated for
the application, connect 1 wire of the twisted pair to one
SEN terminal and connect the other wire to the other
SEN terminal located under the cover of the space
temperature sensor.

2. Connect the other ends of the wires to terminals 5 and 6
on TB5 located in the unit control box.

Units on the SCN can be monitored from the space at the
sensor through the RJ11 connector, if desired. To wire the RJ11
connector into the SCN (Fig. 10):

IMPORTANT: The cable selected for the RJ11 connector
wiring MUST be identical to the SCN communication bus
wire used for the entire network. Refer to Table 5 for
acceptable wiring.

1. Cut the SCN wire and strip ends of the red (+), white
(ground), and black (–) conductors. (If another wire color
scheme is used, strip ends of appropriate wires.)

2. Insert and secure the red (+) wire to terminal 5 of the
space temperature sensor terminal block.

3. Insert and secure the white (ground) wire to terminal 4 of
the space temperature sensor.

4. Insert and secure the black (–) wire to terminal 2 of the
space temperature sensor.

5. Connect the other end of the communication bus cable to
the remainder of the SCN communication bus.

T10 — Dual Leaving Water Temperature Sensor

— For
dual chiller applications (parallel only are supported), connect
the dual chiller leaving fluid temperature sensor (5 k Ω ther-
mistor, Sterling part no. HH79NZ029) to the space temperature
input of the Master chiller. If space temperature is required for
reset applications, connect the sensor to the S lave chiller and
configure the slave chiller to broadcast the value to the Master
chiller.

LEGEND FOR FIG. 1-6

ALMR — Alarm Relay
BR — Boiler Relay
C—Contactor, Compressor
CB — Circuit Breaker
CCB — Compressor Circuit Breaker
CHC — Cooler/Pump Heater Contactor
COMP — Compressor
CWFS — Chilled Water Flow Switch
CWP — Chilled Water Pump
DPT — Discharge Pressure Transducer
EMM — Energy Management
FIOP — factory Installed Option
FM — Fan Motor
GND — Ground
HPS — High-Pressure Switch
HR — Heat Relay
ICP — Inrush Current Protection
IP — Internal Protection Thermostat
LW T — Leaving Water Temperature
MBB — Main Base Board
MLV — Minimum Load Valve
MS — Manual Starter
OAT — Outdoor-Air Thermistor
OL — Overload
R—Relay
SPT — Suction Pressure Transducer
SW — Switch
T—Thermistor
TB — Te r mi na l B l oc k
TNKR — Storage Tank Heater Relay
TRAN — Transformer

Te r m in al Bl o ck

Terminal (Unmarked)

Terminal (Marked)

Splice

Factory Wiring

Field Wiring

Accessory or Option Wiring

To indicate common potential only;
not to represent wiring.

5

Fig. 1 — Typical Control Box for 30RA010-030 (022-030 Shown)

6

Fig. 2 — Typical Control Box for 30RA032-055 (042-055 Shown)

7

30RA010-018 AQUA SNAP

Fig. 3 — Wiring Schematic 30RA010-018

8

AQUA-SNAP LOW VOLTAGE CONTROL SCHEMATIC (010-018)

SEE NOTE 8

SEE NOTE 8

Fig. 3 — Wiring Schematic 30RA010-018 (cont)

9

30RA022-030 AQUA SNAP

Fig. 4 — Wiring Schematic 30RA022-030

10

AQUA-SNAP LOW VOLTAGE CONTROL SCHEMATIC (022-030)

Fig. 4 — Wiring Schematic 30RA022-030 (cont)

11

30RA032-040 AQUA SNAP

Fig. 5 — Wiring Schematic 30RA032-040

12

AQUA-SNAP LOW VOLTAGE CONTROL SCHEMATIC (032-040)

Fig. 5 — Wiring Schematic 30RA032-040 (cont)

13

30RA042-055 AQUA SNAP

Fig. 6 — Wiring Schematic 30RA042-055

14

AQUA-SNAP LOW VOLTAGE CONTROL SCHEMATIC (042-055)

Fig. 6 — Wiring Schematic 30RA042-055 (cont)

15

RED LED - STATUS GREEN LED -

LEN (LOCAL EQUIPMENT NETWORK)

CEPL130346-01

YELLOW LED ­SCN (STERLCO COMFORT NETWORK)

INSTANCE JUMPER

K11

K10 K9

J1

J4

J6

Run Status

Service Test

Temperature

Pressures

Setpoints

Inputs

Outputs

Configuration

Time Clock

Operating Modes

Alarms

J2

J3

J5

MODE

J7

Alarm Status

ESCAPE

LEN

SCN

STATUS

J8

Fig. 7 — Main Base Board

ENTER

SW1

SW2

K4

REMOTE

CONTACT

ENABLE

OFF

ON

CB1

K8

OFF

K7

K3 K2

TB3

LEN

SCN

(COM)

CN

SHIELD

K6

K5

J10

K1

J9

ENABLE/OFF/REMOTE
CONTACT SWITCH

(+)

SCN

(-)

COMMUNICATIONS

EMERGENCY
ON/OFF SWITCH

CB2

Fig. 8 — LEN/SCN Interface, Enable/Off/Remote Contact Switch, and Emergency On/Off Switch Locations

16

SPT (T10) PART NO. 33ZCT55SPT

SENSOR

SEN

SEN

TB5

5

6

Fig. 9 — Typical Space Temperature

Sensor Wiring

T-55 SPACE
SENSOR

6

TO SCN
COMM 1
BUS (PLUG)
AT UNIT

SCN+

SCN GND

SCN-

5

4

3

2

1

Fig. 10 — SCN Communications Bus Wiring

to Optional Space Sensor RJ11 Connector

Energy Management Module (Fig. 11) —

This
factory-installed option (FIOP) or field-installed accessory is
used for the following types of temperature reset, demand
limit, and/or ice features:

• 4 to 20 mA leaving fluid temperature reset (requires

field-supplied 4 to 20 mA generator)

• 4 to 20 mA cooling set point reset (requires field-

supplied 4 to 20 mA generator)

• Discrete inputs for 2-step demand limit (requires field-

supplied dry contacts capable of handling a 24 vac,
50 mA load)

• 4 to 20 mA demand limit (requires field-supplied 4 to

20 mA gener ator)

• Discrete input for Ice Done switch (requires field-

supplied dry contacts capable of handling a 24 vac,
50 mA load)

See Demand Limit and Temperature Reset sections on

pages 44 and 43 for further details.

Care should be taken when interfacing with other manufac­turer’s control systems due to possible power supply
differences, full wave bridge versus half wave rectification.
The two different power supplies cannot be mixed.
ComfortLink™ controls use half wave rectification. A
signal isolation device should be utilized if a full wave
bridge signal generating device is used.

Loss-of-Cooler Flow Protection —

A proof-of-cooler
flow device is factory installed in all chillers. It is recommended
that proper operation of the switch be verified on a regular basis .

Thermostatic Expansion Valves (TXV) —

All units

are equipped from the factory with conventional TXVs. Each

refrigeration circuit is also supplied with a factory-installed
liquid line filter drier and sight glass.

The TXV is set at th e factory to maintain approxim ately 8 to
12° F (4.4 to 6.7° C) suction superheat leaving the cooler by
metering the proper amount of refrigerant into the cooler. All
TXVs are adjustable, but should not be adjusted unless
absolutely necessary.

The TXV is designed to limit the cooler saturated suction
temperature to 55 F (12.8 C). This makes it possible for unit to
start at high cooler fluid temperatures without overloading the
compressor.

Capacity Control —

The control system cycles com­pressors, and minimum load valve solenoids (if equipped) to
maintain the user-configured leaving chilled fluid temperat ure
set point. Entering fluid temperature is used by the Main Base
Board (MBB) to determine the temperature drop across the
cooler and is used in determining the optimum time to add or
subtract capacity stages. The chilled fluid temperature set point
can be automatically reset by the return fluid temperature,
space, or outdoor-air temperature reset features. It can also be
reset from an external 4 to 20-mA signal (requires Energy
Management Module FIOP or accessory).

The control has an automatic lead-lag feature built in which
determines the wear factor (combination of starts and run
hours) for each compressor. If all compressors are off and less
than 30 minutes has elapsed since the last compressor was
turned off, the wear factor is used to determine which compres­sor to start next. If no compressors have been running for more
than 30 minutes and the leaving fluid temperature is greater
than the saturated condensing temperature, the wear factor is
still used to determine which compressor to start next. If the
leaving fluid temperature is less than the saturat ed condensing
temperature, then the control will start either compressor A1 or
compressor B1 first, depending on the user-configurable circuit
lead-lag value.

The TXVs will provide a controlled start-up. During start­up, the low pressure logic will be bypa ssed for 2

1

/2 minutes to
allow for the transient changes during start-up. As additional
stages of compression are required, the processor control will
add them. See Table 6 and 7.

If a circuit is to be stopped, the compressor with t he lowe st
wear factor will be shut off first in most cases. Certain override
conditions may shut off the smaller of two compressors on a
circuit first.

The capacity control algorithm runs every 30 seconds. The
algorithm attempts to main tain the Control Point at the desired
set point. Each time it runs, the control reads the entering and
leaving fluid temperatures. The control determines t he rate at
which conditions are changing and calculates 2 variables based
on these conditions. Next, a capacity ratio is calcul ated using
the 2 variables to determine whether or not to make any
changes to the current stages of capacity. This ratio value
ranges from –100 to +100%. If the next stage of capacity is a
compressor, the control starts (stops) a compressor when the
ratio reaches +100% (–100%). If installed, the minimum load
valve solenoid will be energized with the first stage of capacity.
Minimum load valve value is a fixed 30% in the total capacity
calculation. The control will also use the minimum load valve
solenoid as the last stage of capacity before turning off the last
compressor. If the close control feature (CLS.C) [Configura­tion, OPT2] is enabled the control will use the minimum load
valve solenoid whenever possible to fine tune leaving fluid
temperature control. A delay of 90 seconds occurs after each
capacity step change. Refer to Tables 6 and 7.

17

CEBD430351-0396-01C

PWR

J1

J2

J4 J3

J5

RED LED - STATUS

LEN

STATUS

J6

GREEN LED ­LEN (LOCAL EQUIPMENT NETWORK)

Fig. 11 — Energy Management Module

J7

ADDRESS
DIP SWITCH

TEST 1

CEPL130351-01

TEST 2

Table 6 — Part Load Data Percent Displacement, Standard Units without Minimum Load Valve

30RA UNIT SIZE

010,015 (60 Hz)

015 (50 Hz), 018

022 (60 Hz)

022 (50 Hz), 025, 030

032, 035 (60 Hz)

035 (50 Hz)

040

042, 045 (50 Hz), 050,

055

045 (60 Hz)

NOTE: These capacity steps may vary due to different capacity staging sequences.

CONTROL

STEPS

1 100 A1 ——
150A1——

2 100 A1,A2 ——
142A1——

2 100 A1, A2 ——
150A1 ——

2 100 A1,A2 ——
1 25A1 40B1

2 60 A1,A2 65 A1,B1
3 100 A1,A2,B1 100 A1,A2,B1

1 33A1 33B1
2 67 A1, A2 67 A1, B1
3 100 A1, A2, B1 100 A1, A2, B1

1 32A1 37B1
2 63 A1, A2 68 A1, B1
3 100 A1, A2, B1 100 A1, A2, B1

1 25A1 25B1
2 50 A1,B1 50 A1,B1
3 75A1,A2,B1 75A1,B1,B2

4 100 A1,A2,B1,B2 100 A1,A2,B1,B2

1 22A1 22B1
2 44 A1,B1 44 A1,B1

3 72A1,A2,B1 72A1,B1,B2

4 100 A1,A2,B1,B2 100 A1,A2,B1,B2

% Displacement Compressor % Displacement Compressor

LOADING SEQ A LOADING SEQ B

18

Table 7 — Part Load Data Percent Displacement, Standard Units with Minimum Load Valve

30RA UNIT SIZE

010 (50/60 Hz)

015 (60 Hz)

015 (50 Hz)

018 (50/60 Hz)

022 (50/60 Hz)

025 (50/60 Hz)

030

032

035 (50/60 Hz)

040

042

045 (60 Hz)

045 (50 Hz), 050

055

*Minimum Load Valve energized.
NOTE: These capacity steps may vary due to different capacity

staging sequences.

CONTROL

STEPS

1
2

1
2

1
2
3

1
2
3

1
2
3

1
2
3

1
2
3

1
2
3
4

1
2
3
4

1
2
3
4

1
2
3
4
5

1
2
3
4
5

1
2
3
4
5

1
2
3
4
5

% Displacement Compressor % Displacement Compressor

69/ 71

100/100

32/ 31
50/ 50

100/100

27/ 35
42/ 50

100/100

38/ 37
50/ 50

100/100

16/25
25/33
60/67

LOADING SEQ A LOADING SEQ B

79

100

28
50

100

39
50

100

15
25
60

100

100

24
32
63

100

18
25
50
75

100

15
22
44
72

100

19
25
50
77

100

20
25
50
75

100

A1*

A1

A1*

A1

A1*

A1

A1,A2

A1*

A1

A1,A2

A1*

A1

A1,A2

A1*

A1

A1,A2

A1*

A1

A1,A2

A1*

A1

A1,A2

A1,A2,B1

A1*

A1

A1,A2

A1,A2,B1

A1*

A1

A1,A2

A1,A2,B1

A1*

A1

A1,B1

A1,A2,B1

A1,A2,B1,B2

A1*

A1

A1,B1

A1,A2,B1

A1,A2,B1,B2

A1*

A1

A1,B1

A1,A2,B1

A1,A2,B1,B2

A1*

A1

A1,B1

A1,A2,B1

A1,A2,B1,B2

—
—

—
—

—
—
—

—
—
—

—
—
—

—
—
—

—
—
—

30
40
65

100

32/25
40/33
65/67

100

29
37
68

100

18
25
50
75

100

15
22
44
72

100

19
25
50
77

100

20
25
50
75

100

—
—

—
—

—
—
—

—
—
—

—
—
—

—
—
—

—
—
—

B1*

B1

A1,B1

A1,A2,B1

B1*

B1

A1,B1

A1,A2,B1

B1*

B1

A1,B1

A1,A2,B1

B1*

B1

A1,B1

A1,B1,B2

A1,A2,B1,B2

B1*

B1

A1,B1

A1,B1,B2

A1,A2,B1,B2

B1*

B1

A1,B1

A1,B1,B2

A1,A2,B1,B2

B1*

B1

A1,B1

A1,B1,B2

A1,A2,B1,B2

19

MINUTES LEFT FOR START — This value is displayed
only in the network display tables (using Service Tool,
ComfortVIEW™ or ComfortWORKS® software) and
represents the amount of time to elapse before the unit will start
its initialization routine. This value can be zero without the
machine running in many situations. This can include being
unoccupied, ENABLE/OFF/REMOTE CONTACT switch in
the OFF position, SCN not allowing unit to start, Demand
Limit in effect, no call for cooling due to no load, and alarm or
alert conditions present. If the machine should be running and
none of the above are true, a minimum off time (DELY, see
below) may be in effect. The machine should start normally
once the time limit has expired.

MINUTES OFF TIME (DELY) [Configuration OPT2] —
This user-configurable time period is used by the control to
determine how long unit operation is delayed a fter power is
applied/restored to the unit. Typically, this time pe riod is con­figured when multiple machines are located on a single site.
For example, this gives the user the abilit y to prevent all the
units from restarting at once after a power failure. A value of
zero for this variable does not mean that the unit should be
running.

LEAD/LAG DETERMINATION — This is a configurable
choice and is factory set to be automatic for all units. The value
can be changed to Circuit A or Circuit B leading as desired. Set
at automatic, the control will sum the current number of logged
circuit starts and one-quarter of the current operating hours for
each circuit. The circuit with the lowest sum is started first.
Changes to which circuit is the lead circuit and which is the lag
are also made when total machine capacity is at 100% or when
there is a change in the direction of capacity (increase or
decrease) and each circuit’s capacity is equal.

CAP ACITY CONTROL OVERRIDES — The following over­rides will modify the normal operation of the routine.

Deadband Multiplier

— The user configurable Deadband
Multiplier (Z.GN) [Configuration, SLCT] has a default value
of 1.0. The range is from 1.0 to 4.0. When set to other than 1.0,
this factor is applied to the capacity Load/Unload Factor. The
larger this value is set, the longer the control will delay between
adding or removing stages of capacity. Figure 12 shows how
compressor starts can be reduced over time if the leaving water
temperature is allowed to drift a larger amount above and be­low the set point. This value should be set in the range of 3.0 to

4.0 for systems with small loop volumes.
First Stage Override

— If the current capa city stage is zero,
the control will modify the routine with a 1.2 fac tor on adding
the first stage to reduce cycling. This factor is also applied
when the control is attempting to remove the last stage of
capacity.

Slow Change Override

— The control prevents the capacity
stages from being changed when the leaving fluid temperature
is close to the set point (within an adjustable deadband) and
moving towards the set point.

Ramp Loading

(CRMP) [Configuration, SLCT] — Limits the
rate of change of leaving fluid temperature. If the unit is in a
Cooling mode and configured for Ramp Loading, the control
makes 2 comparisons before deciding to change stages of ca­pacity. The control calculates a temperature difference between
the control point and leaving fluid temperature. If the differ­ence is greater than 4 °F (2.2 °C) and the rate of change (°F or
°C per minute) is more than the configured Cooling Ramp
Loading value (CRMP), the control does not allow any chang­es to the current stage of capacity.

Low Entering Fluid Temperature Unloading

— When the
entering fluid temperature is below the control point, the
control will attempt to remove 25% of the current stages being
used. If exactly 25% cannot be removed, the control removes
an amount greater than 25% but no more than necessary. The
lowest stage will not be removed.

Minimum Load Control

— If equipped, the minimum load
control valve is energized only when one compressor in the
circuit is running. If the close control feature is enabled the
minimum load control valve may be used as needed to obtain
leaving fluid temperature close to set point.

Cooler Freeze Protection

— The control will try to prevent
shutting the chiller down on a Cooler Freeze Protection ala rm
by removing stages of capacity. If the cooler fluid selected
is Water, the freeze point is 34 F (1.1 C). If the cooler fluid
selected is Brine, the freeze point is the Brine freeze Point
(BR.FZ) [Set Points, FRZ]. This alarm condition (A207) only
references leaving fluid temperature and NOT Brine Freeze
point. If the cooler leaving fluid temperature i s less than the
freeze point plus 2.0° F (1.1° C), the control will immediately
remove one stage of capacity. This can be repeated once every
30 seconds.

Low Saturated Suction Protection

— The control will try to
prevent shutting a circuit down due to low saturated suction
conditions by removing stages of capacity. These circuit alert
conditions (T116, T117) compare saturated suction tempera­ture to the configured Brine Freeze point (BR.FZ) [Set Points,
FRZ]. The Brine Freeze point is a user-configurable value that
must be left at 34 F (1.1 C) for 100% wate r sys tems. A lower
value may be entered for systems with brine solutions, but this
value should be set according to the freeze protection level of
the brine mixture. Failure to properly set this brine freeze point
value may permanently damage the brazed plate heat exchang­er. The control will initiate Mode 7 (Circuit A) or Mode 8 (Cir­cuit B) to indicate a circuit’s capacity is limited and that even­tually the circuit may shut down.

LEGEND

Leaving Water Temperature

LWT —

LWT (C)

MODIFIED
DEADBAND

2 STARTS

3 STARTS

DEADBAND EXAMPLE

47

8

46

45

7

44

43

LWT (F)

6

42

5

41

0 200 400 600 800 1000

TIME (SECONDS)

STANDARD
DEADBAND

Fig. 12 — Deadband Multiplier

20

Head Pressure Control —

The Main Base Board
(MBB) controls the condenser fans to maintain the lowest
condensing temperature possible, and thus the highest unit
efficiency. The MBB uses the saturated condensing tempera­ture input from the discharge pressure transducer to control the
fans. Head pressure control is maintained through a calculated
set point which is automatically adjusted based on actual

160

140

120

105

100

SCT (F)

80

60

47.5

40

-10 -5

LEGEND

SCT —
SST —

05

Saturated Condensing Temperature
Saturated Suction Temperature

10

15

20

R-22 SST (F)

25 30

149

35 40 45 50 55

154

78

Fig. 13 — Operating Envelope for

R-22 Maneurop Compressor

saturated condensing and saturated suction temperatures so
that the compressor(s) is (are) always operating within the
manufacturer's specified envelope (see Fig. 13). The control
will automatically reduce the unit capacity as the saturated
condensing temperature approaches an upper limit. The
control will indicate through an alert that a high ambient
unloading mode is in effect. If the saturated condensing
temperature in a circuit exceeds the calculat ed maximum, the
circuit will be stopped. For these reasons, there are no head
pressure control methods or set points to enter. If the saturated
condensing temperature in a circuit is greater than or e qual to
95 F (35 C) at start-up, all available condenser fans will be
started to prevent excessive discharge pressure during
pull-down. The control will turn off a fan stage when the
condensing temperature has been below the calculated head
pressure set point by 35 F (19.4 C) for more than 2 minutes.
Fan sequences are shown in Fig. 14.

MOTORMASTER® V OPTION — For low-ambient opera­tion, the lead fan on a circuit can be equipped with the
Motormaster V head pressure controller option or accessory.
The control will automatically raise the head pressure set point
by 5 F (2.8 C) when Motormaster control is configured. The
controller is energized with the first fan stage and adjusts fan
speed to maintain a liquid pressure of 135 psig (931 kPa). For
sizes 010-018 and Circuit B of sizes 032-040, the two-speed
fan is wired for high speed operation and the Motormaster V
controller adjusts fan speed. For size 022-030, 042-055 and
circuit A of the 032-040 sizes, the lead fan (A1 or B1) in the
circuit is controlled. Refer to Fig. 14 for condenser fan staging
information. Refer to Fig. 15 for typical pressure transducer
location.

FAN ARRANGEMENT FAN NO. FAN RELAY NORMAL CONTROL

30RAN010-018

CONTROL
BOX
END

30RAN022-030

CONTROL
BOX
END

30RAN032-040

CONTROL
BOX
END

30RAN042-055

CONTROL
BOX
END

1

1 2

1 2

3

1 2

3 4

1FC-LS

1FC-HS

1FC-A1

2FC-A2

1FC-A1

2FC-A2

3FC-LS

3FC-HS

1FC-A1

2FC-A2

3FC-B1

4FC-B2

Energize Fan at

Low Speed

Energize Fan at

High Speed

First Stage

Condenser Fan

Second Stage

Condenser Fan

On with Compressor A1

and/or Compressor A2

First Stage Condenser

Fan, Circuit A

Low Speed, Fan on

w/Compressor B1

Energize Fan at High Speed,

First Stage Condenser Fan,

First Stage Condenser Fan,

Circuit B

On with Compressor A1

and/or Compressor A2

Circuit A

On with Compressor B1

and/or Compressor B2

Circuit B

Fig. 14 — 30RA Condenser Fan Sequence

21

DETAIL A

PRESSURE TRANSDUCER
INSTALLED HERE

SEE DETAIL A

Fig. 15 — Typical Motormaster® V Controller and Pressure Transducer Location (Sizes 022-030 Shown)

Operation of Machine Based on Control
Method and Cooling Set Point Selection Set­tings —

configuration of the control method (CTRL) [Configuration,
OPT2] and cooling set point select (CLSP) [Configuration,
SLCT] variables. All models are factory confi gured with cool­ing set point select set to 1 (single set point, CSP1). With the
control method set to 0, simply switching the Enable/Off/Re­mote Contact switch to the Enable or Remote Contact position
(external contacts closed) will put the chiller in an occupied
state. The control mode [Operating Modes, MODE] will be 1
(OFF LOCAL) when the sw itch is Off an d wi ll be 5 (O N LO­CAL) when in the Enable position or Remote Contact position
with exte rn al cont ac ts clo se d.

Two other control methods are avai lable for Machine On/

Off control:
OCCUPANCY SCHEDULE (CTRL=2) — The Main Base

Board will use the operating schedules as defined under the
Time Clock mode in the Marquee display. These schedules are
identical. The schedule number must be set to 1 for local
schedule.

The schedule number can be set anywhere from 65 t o 99
for operation under a SCN global schedule. The Enable/Off/
Remote Contact must be in the Enable or Remote Contact posi­tion. The control mode [Operating Modes, MODE] will be 1
when the switch is Off. The control mode will be 3 when the
Enable/Off/Remote Contact switch input is On and the time of
day is during an unoccupied period. Similarly, the control
mode will be 7 when the time of day is during an occupied
period.

SCN SCHEDULE (CTRL=3) — An external SCN device
such as Flotronic™ System Manager controls the On/Off state
of the machine. This SCN device forces the variable
‘CHIL_S_S’ between Start/Stop to control the chiller. The
control mode [Operating Modes, MODE] will be 1 when the
switch is Off. The control mode will be 2 when the Enable/Off/
Remote Contact switch input is On and the CHIL_S_S variable
is ‘Stop.’ Similarly, the control mode will be 6 when the
CHIL_S_S variable is ‘Start.’

Machine On/Off control is determined by the

Table 8 illustrates how the control method and cooling set
point select variables direct the operation of the chiller and the
set point to which it controls. The illustration also shows the
ON/OFF stat e of th e ma chi ne fo r t he gi ven co mbin at ions .

Cooling Set Point Select

SING LE — Unit operation is based on Cooling Set Point 1
(CSP1) [Set Point, COOL].

DUAL SWITCH — Unit operation is based on Cooling Set
Point 1 (CSP1) [Set Po int, COOL] when the Dual Set Point
switch contacts are open and Cooling Set Point 2 (CSP2)
[Set Point, COOL] when they are closed.

DUAL SCN OCCUPIED — Unit operation is based on
Cooling Set Point 1 (CSP1) [Set Point, COOL] during the
Occupied mode and Cooling Set Point 2 (CSP2) [Set Point,
COOL] during the Unoccupied mode as configured under the
local occupancy schedule accessible only from SCN. Schedule
Number in Table SCHEDOVR (See Appendix A) must be
configured to 1. If the Schedule Number is set to 0, the unit will
operate in a continuous 24-hr Occupied mode. Control method
must be configured to 0 (switch). See Table 8.

4 TO 20 mA INPUT — Unit operation is based on an external
4 to 20 mA signal input to the Energy Management Module
(EMM).

LOW SOUND MODE OPERATION — All models are fac­tory configured with the Low Sound Mode disabled. In the
Configuration mode under sub-mode OPT2, items for low
sound mode select (LS.MD), low sound start time (LS.ST),
low sound end time (LS.ND) and low sound capacity limit
(LS.LT) are factory configured so that the chiller always runs
as quietly as possible. This results in operation at increased
saturated condensing temperature. As a result, some models
may not be able to achieve rated efficiency. For chiller opera­tion at rated efficiency, disable the low sound mode or adjust
the low sound mode start and stop times accordingly or set both
times to 00:00 for rated efficiency operation 24 hours per day.
In addition, the low sound capacity limit can be used to reduce
overall chiller capacity, if required, by limiting the maximum to
a user-configured percentage.

22

Table 8 — Control Methods and Cooling Set Points

ENTER

ENTER

ENTER

ENTER

CONTROL

TYPE

(CTRL)

0 (switch)

2 (Occupancy)

3 (SCN)

*Dual set point switch input used. CSP1 used when switch input is open. CSP2 used when switch input is closed.

†Cooling set point determined from 4 to 20 mA input to Energy Management Module (EMM) to terminals TB6-3,5.

OCCUPANCY

STATE

Occupied ON,CSP1 ON* ON,CSP1 ON†
Unoccupied ON,CSP1 ON* ON,CSP2 ON
Occupied ON,CSP1 ON* Illegal ON†
Unoccupied OFF OFF Illegal OFF
Occupied ON,CSP1 ON* ON,CSP1 ON†
Unoccupied ON,CSP1 ON* ON,CSP2 ON†

0

(single)

HEATING OPERATION — The chiller can be used for
pump outputs or optional factory-installed hydronic system
operation can be utilized for heating applications. The heating
mode is activated when the control sees a field-supplied closed
switch input to terminal block TB5-7,8. The control locks out
cooling when the heat relay input is seen. A field-supplied
boiler relay connection is made using heat relay and alarm
relay contacts. Factory-installed ‘BOILER’ connections exist
in the control panel near TB5 for these applications. Alarms
and alerts A189 through A202 are active during heating
operation.

Marquee Display Usage (See Fig. 16 and
Tables 8-27) —

user interface to the ComfortLink™ control system. The
display has up and down arrow keys, an key, and an

ENTER

different levels of the display structure. See Table 9. Press the

ESCAPE
top 11 mode levels indicated by LEDs on the left side of the
display .

will scroll a clear language text description across the display
indicating the full meaning of each display acronym. Pressing
the and keys when the display is bl ank
(Mode LED level) will return the Marquee display to its default
menu of rotating display items. In addition, the password will
be disabled requiring that it be entered again before changes
can be made to password protected items.

Portuguese can be displayed when properly configuring the
LANG Item in the Configuration Mode, under the Display
(DISP) submode. See Table 17. Throughout this text, the loca­tion of items in the menu structure will be described in the fol­lowing format:

Item Expansion (ITEM) [Mode Name, Sub-mode Name]
For example, using the language selection item:
Language Selection (LANG) [Configuration, DISP]

key. These keys are used to navigate through the

key until the display is blank to move through the

Pressing the a nd keys simultaneously

ESCAPE ENTER

Clear language descriptions in English, Spanish, French, or

The Marquee display module provides the

ESCAPE

ESCAPE ENTER

COOLING SET POINT SELECT (CLSP)

1

(dual, switch)

(dual, occ)

NOTE: When the LANG variable is c hanged to 1, 2, or 3, all
appropriate display expansions will immediately change to the
new language. No power-off or control reset is required when
reconfiguring languages.

When a specific item is located, the display will flash show­ing the operator, the item, followed by the item value and then
followed by the item units (if any). Press the key to
stop the display at the item value. Items in the Configuration
and Service Test modes are password protected. The display
will flash PASS and WORD when required. Use the
and arrow keys to enter the 4 digits of the password. The
default password is 1111.

Changing item values or testing outputs is accomplished in
the same manner. Locate and display the desired item. Press

to stop the display at the item value. Press the
key again so that the item value flashes. Use the

arrow keys to change the value or state of an item and press the

key to accept it. Press the key and the
item, value, or units display will resume. Repeat the process as
required for other items.

See Tabl es 8-27 for further details.

Service Test (See Table 11) —

and control cir cuit power must be on.

The Service Test function should be used to verify proper
operation of condenser fan(s), compressors, minimum load
valve solenoid (if installed), cooler pump(s) and remote alarm
relay. To use t he Service Test mode, the Enable/Off/Remote
Contact switch must be in the OFF position. Use the display
keys and Table 11 to enter the mode and display TEST. Press

twice so that OFF flashes. Enter the password if
required. Use either arrow key to change the TEST value to the
ON position and press . Press and the
button to enter the OUTS or COMP sub-mode.

T est the condenser fans, cooler pump(s) and alarm relay by

changing the item values from OFF to ON. These discrete

ENTER ESCAPE

outputs are then turned off if there is no keypad activity for
10 minutes. Test the compressor and minimum load valve
solenoid (if installed) outputs in a similar manner. The

MODE

Run Status

Service Test

Temperature

Pressures

Setpoints

Inputs

Outputs

Configuration

Time Clock

Operating Modes

Alarms

Alarm Status

ESCAPE

ENTER

minimum load valve solenoids will be turned off if there is no
keypad activity for 10 minutes. Compressors will stay on until
they are turned off by the operator. The Service Test mode will
remain enabled for as long as there is one or more compressors
running. All safeties are monitored during this test and will turn
a compressor, circuit or the machine off if required. Any other
mode or sub-mode can be accessed, viewed, or changed during
the TEST mode. The STAT item [Run/Status, VIEW] will dis­play “0” as long as the Service mode is enabled. The TEST
sub-mode value must be changed back to OFF before the chill-

Fig. 16 — Scrolling Marquee Display

er can be switched to Enable or Remote contact for normal
operation.

2

3

(4 to 20 mA)

ENTER

ENTER

ESCAPE

Both main power

23

Optional Factory-Installed Hydronic Package —

If the chiller has factory-installed chilled fluid pumps, specific
steps should be followed for proper operation.

The pump(s) in the hydronic package come factory
pre-wired into the main unit power supply/starter. In order to
check proper pump rotation, use the Service Test function to
test the condenser fans and observe them for proper rotation
(counter clockwise when viewed from the top). If fans turn
correctly, the pumps will rotate corr ectly. Clockwise rotation of
the pump motor cooling fans can also be used to determine that
pumps are rotating correctly.

Operation of pump in wrong direction, even for a few
seconds, can cause irreversible damage t o pump impeller
and housing. Always verify correct wiring/pump rotation
before operation.

Use Service T est function to test operation of pumps. Verify
that the flow switch input is made when the pump is running.
For dual pump hydronic systems, the control only uses one
pump at a time. Consult the Installation Instructions supplied
with this chiller and use the circuit setter balancing valve
installed in hydronic package to adjust fluid flow rate.

Cooler Pump Control —

chines equipped with a factory installed pump package are
configured with the Cooler Pump Control (CPC) [Configura­tion, OPT1] ON.

Machines not equipped with a pump package are config­ured with the cooler pump control OFF. It is recommended that
the machine control the chilled water pump. If not, a 5-minute
time delay is required after the command to shut the machine
down is sent before the chilled water pump is turned off. This is
required to maintain water flow during the shutdown period of
the machine.

With or without this option enabled, the cooler pump relay
will be energized when the mac hine enters an ON status (i.e.,
On Local, On SCN, On Time). An A207 - Cooler Freeze
Protection Alarm, will energize the cooler pump relay also, as
an override. The cooler pump relay will remain energized if the
machine is in MODE 10 – Minimum Off Time.

Cooler Pump Sequence of Operation —

time the unit is in an ON status, as defined by the one of the
following conditions, the cooler pump relay will be enabled.

1. The Enable-Off-Remote Switch in ENABLE,
(CTRL=0).

2. Enable-Off-Remote Switch in REMOTE with a
Start-Stop remote contact closure, (CTRL=0).

3. An Occupied Time Period from an Occupancy Schedule
in combination with items 1 or 2, (CTRL=2).

4. A SCN Start-Stop Command to Start in combination
with items 1 or 2, (CTRL=3).

As stated before, there are certain alarm conditions and
Operating Modes that will turn the cooler pump relay ON. This
sequence will describe the normal operation of the pump
control algorithm.

When the unit cycles from an “On” state to an “ Off” state,
the cooler pump output will remain energized for the Cooler
Pump Shutdown Delay (PM.DY) [Configuration, OPT1]. This
is configurable from 0 to 10 minutes. The factory default is 1
minute. If the pump output was deenergized during the transi­tion period, the pump output will not be energized.

NO INTEGRAL PUMP — SINGLE EXTERNAL PUMP
CONTROL — With a single external pump, the following
options must be configured:

• Cooler Pump Control (CPC) [Configuration, OPT1]

OFF.

The 30RA AquaSnap® ma-

At any-

• Cooler Pump 1 Enable (PM1E) [Configuration, UNIT]
NO.

• Cooler Pump 2 Enable (PM2E) [Configuration, UNIT]
NO.

The maximum load allowed for the Chilled Water Pump

Starter is 5 VA sealed, 10 VA inrush at 24 volts. The starter coil
is powered from the chiller control system. The starter s hould
be wired between TB5-11 and TB5-13. If equipped, the field­installed chilled water pump starter auxiliary contacts should
be connected in series with the chilled water flow switch.

The Cooler Pump Relay will be energized when the

machine is “On.” The chilled water pump interlock circuit
consists of a chilled water flow switch and a field-installed
chilled water pump interlock. If the chilled water pump inter­lock circuit does not close within five (5) minutes of starting,
an A200 — Cooler Flow/Interlock failed to close at Start-Up
alarm will be generated and chiller will not be allowed to start.

If the chilled water pump in terlock or chilled water flow

switch opens for at least three (3) seconds after initially being
closed, an A201 — Cooler Flow/Interlock Contacts Opened
During Normal Operation Alarm will be generated and the ma­chine will stop.

NO INTEGRAL PUMP — DUAL EXTERNAL PUMP
CONTROL — With two external pumps, the following
options must be configured:

• Cooler Pump Control (CPC) [Configuration, OPT1] ON.

• Cooler Pump 1 Enable (PM1E) [Configuration, UNIT]
YES.

• Cooler Pump 2 Enable (PM2E) [Configuration, UNIT]
YES.

The maximum load allowed for the Chilled Water Pump

Starters is 5 VA sealed, 10 VA inrush at 24 volts. The st arter
coil is powered from the chiller control system. The starter for
Chilled Water Pump 1 should be wired between TB5-11 and
TB5-13. The starter for Chilled W ater Pump 2 shoul d be wired
between TB5-15 and TB5-13. A field-installed chille d water
pump interlock for each pump must be connected to each
pump’s interlock points on the Main Base Board. The Chilled
Water Pump 1 Interlock, CWP1, must be connected to MBB­J7-1 and –2. The Chilled W ater Pump 2 Interlock, CWP2, must
be connected to MBB-J7-3 and –4. The chilled water pump
interlock contacts should be rated for dry circuit application
capable of handling 5 vdc at 2 mA.

SINGLE INTEGRAL PUMP CONTROL — With a single
pump, the following options must be configured:

• Cooler Pump Control (CPC) [Configuration, OPT1] ON.

• Cooler Pump 1 Enable (PM1E) [Configuration, UNIT]
YES.

• Cooler Pump 2 Enable (PM2E) [Configuration, UNIT]
NO.

With a single integral pump, the Cooler Pump Starter will

be energized when the machine is occupied. As part of the
factory-installed package, an auxiliary set of contacts is wired
to the MBB to se rve as Chilled Water Pump Interlock. W hen
the mechanical cooling is called for, the pump interlock and
flow switch is checked. If the circuits are c losed, the machine
starts its capacity routine. If the auxiliary contact interlock does
not close within 25 seconds of the ON command, a T190 —
Cooler Pump 1 Aux Contacts Failed to Close at Start-Up Alert
will be generated and the pump shut down. The unit will not
be allowed to start. If the chilled water flow switch does not
close within one (1) minute, two alarms will be generated. A
T192 — Cooler Pump 1 Failed to Provide Flow at Start-Up
Alert and an A200 – Cooler Flow/Interlock failed to close at
Start-Up will be generated and chiller will not be allowed to
start.

If the chilled water flow switch opens for at least 3 seconds

after initially being closed, a T196 — Flow Lost While Pump 1
Running Alert and an A201 — Cooler Flow/Interlock Contacts

24

Opened During Normal Operation Alarm will be generated
and the machine will stop.

If the control detects the chilled water pump interlock open
for 25 seconds after initially being closed, a T194 — Cooler
Pump 1 Contacts Opened Duri ng Normal Operation Alert is
generated and the unit is shut down.

If the control detects the chilled water flow switch circuit
closed for at least 5 minutes with the pump output OFF, an
A202 — Cooler Pump Interlock Closed When Pump is Off
Alarm will be generated and the unit will not be allowed to
start.

If the control detects that the chilled water pump auxiliary
contacts are closed for at least 25 seconds while the pump is
OFF, a T198 — Cooler Pump 1 Aux Contacts Closed While
Pump Off A l e r t i s generated. The ch il le r will not be allowe d to
start.

If the control starts a pump and the wrong interlock circuit
closes for at least 20 seconds, an A189 — Cooler Pump and
Aux Contact Input Miswire Alarm will be generated. The unit
will be prevented from starting.

As part of a pump maintenance routine, the pump can be
started to maintain lubrication of the pump seal. To utilize this
function, Cooler Pmp Periodic Start (PM.P.S) [Configuration,
UNIT] must be se t to YES. This option i s se t to N O a s th e f a c­tory default. With this feature enabled, if the pump is not oper­ating, it will be started and operated for 2 seconds starting at
14:00 hours. If the pump is operating, this routine is skipped. If
the pump has failed and an Alarm/Alert condition is active, the
pump will not start that day.

DUAL INTEGRAL PUMP CONTROL — With a dual inte­gral pump package, the following options must be configured:

• Cooler Pump Control (CPC) [Configuration, OPT1] ON.

• Cooler Pump 1 Enable (PM1E) [Configuration, UNIT]

YES

• Cooler Pump 2 Enable (PM2E) [Configuration, UNIT]

YES

Pump Start Selection is a field-configurable choice. Cooler
Pump Select (PM.SL) [Configuration, UNIT] is factory de­faulted to 0 (Automatic). This value can be changed to 1 (Pump
1 Starts First) or 2 (Pump 2 Starts First). If PM.SL is 0 (Auto­matic), the pump selection is based on two cri teria: the alert
status of a pump and the operational hours on the pump. If a
pump has an active Alert condition, it will not be considered
for the lead pump. The pump with the lowest operational hours
will be the lead pump. A pump is selected by the control to start
and continues to be the lead pump until the Pump Changeover
Hours (PM.DT) [Configuration, UNIT] is reached. The Lead
Pump (LD.PM) [Run Status, VIEW] indicates the pump that
has been selected as the lead pump: 1 (Pump 1), 2 (Pump 2), 3
(No Pump). The Pump Changeover Hours is factory defaulted
to 500 hours. Regardless of the Cooler Pump Selection, any
pump that has an active alert will not be allowed to start.

With the dual integral pump package, the Cooler Pump
Starter will be energized when the machine is in an occupied
period. As part of the factory-installed package, an au xiliary set
of contacts is wired to the MBB to serve as Chilled Water Pump
Interlock, one set for each pump to individual channels on the
MBB. With a call for mechanical cooling, the specific pump
interlock and flow switch are checked. If the circuits are closed,
the machine starts its capacity routine. If Pump 1 starts and the
auxiliary contact interlock does not close within 25 seconds of
the ON command, a T190 – Cooler Pump 1 Aux Contacts
Failed to Close at Start-Up Alert will be generated and the
pump shut down. The unit will not be allowed to start. If the
chilled water flow switch does not close with in 1 minute, two
alarms will be generated. A T192 – Cooler Pump 1 Failed to
Provide Flow at Start-Up Alert and an A200 – Cooler Flow/
Interlock failed to close at Start-Up will be generated and chiller

will not be allowed to start. In either fault ca se listed above,
Pump 2 will be commanded to start once Pump 1 has fail ed.

If Pump 2 starts and the auxiliary contact interlock does
not close within 25 seconds of the ON command, a T191 —
Cooler Pump 2 Aux Contacts Failed to Close at Start-Up Alert
will be generated and the pump shut down. The unit will not be
allowed to start. If the chilled water flow switch does not close
within one (1) minute, two alarms will be genera ted. A T193
— Cooler Pump 2 Failed to Provide Flow at Start-Up Alert and
an A200 – Cooler Flow/Interlock failed to close at Start-Up
will be generated and chiller will not be allowed to start. In
either fault case listed above, Pump 1 will be commanded to
start once Pump 2 has failed.

If the chilled water flow switch opens for at least 3 seconds
after initially being closed, a T196 — Flow Lost While Pump 1
Running Alert or T197 — Flow Lost While Pump 2 Running
Alert for the appropriate pump and an A201 — Cooler Flow/
Interlock Contacts Opened During Normal Operation Alarm
will be generated and the machine will stop. If ava ilable, the
other pump will be started. If flow is proven, the machine will
be allowed to restart.

If the chilled water pump interlock opens for 25 seconds
after initially being closed is detected by the control, the appro­priate T194 – Cooler Pump 1 Contacts Opened During Normal
Operation Alert or T195 – Cooler Pump 2 Contacts Opened
During Normal Operation Alert is generated and the unit is
shut down. If available, the other pump will be started. If flow
is proven, the machine will be allowed to restart.

If the control detects that the chilled water flow switch
circuit is closed for at least 5 minutes wi th the pump output
OFF, an A202 – Cooler Pump Interlock Closed When Pump is
Off Alarm will be generated and the unit will not be allowed to
start.

If the control detects that the chilled water pump auxiliary
contacts are closed for at least 25 seconds while the pump is
OFF, the appropriate T198 – Cooler Pump 1 Aux Contacts
Closed While Pump Off or Alert T199 – Cooler Pump 2 Aux
Contacts Closed While Pump Off Alert is generated. The
chiller will not b e al lowe d to st art .

If the control starts a pump and the wrong inte rlock circuit
closes for at least 20 seconds, an A189 – Cooler Pump and Aux
Contact Input Miswire Alarm will be generated. The unit will
be prevented from starting.

The control will allow for pump changeover. Tw o methods
will change the pump sequence. Before the changeover can
occur, the unit must be at Capacity Stage 0. During changeover
the chilled water flow switch input is ignored for 10 seconds to
avoid a nuisance alarm.

With Cooler Pump Select (PM.SL) [Configuration, UNIT]
set to 0 (Automatic) and when the differential time limit Pump
Changeover Hours (PM.DT) [Configurat ion, UNIT] is reache d,
the lead pump will be turned OF F. Approximately one (1) sec­ond later, the lag pump will start. Manual changeover can be ac­complished by changing Rotate Cooler Pump Now (ROT.P)
[Configuration, UNIT] to YES only if the machine is at Capac­ity Stage 0 and the differential time limit Pump Changeover
Hours (PM.DT) [Configuration, UNIT] is reached. If the
PM.DT is not satisfied, the changeover will not occur. With the
machine at Capacity Stage 0, the pumps would rotate automati­cally as part of the normal routine.

With Cooler Pump Select (PM.SL) [Configuration, UNIT]
set to 1 (Pump 1 Starts First) or 2 (Pump 2 Starts First), a manual
changeover can be accomplished by changing PM.SL only. The
machine Rem ote-Off-Enable S witch must be in the OFF pos i­tion to change this variable. The Rotate Cooler Pump Now
(ROT.P) [Configuration, UNIT] feature does not work for these
configuration options.

25

As part of a pump maintenance routine, the pumps can be

*Depending on piping sizes, use either:

• HH79NZ014 sensor/10HB50106801 well (3-in. sensor/well)

• HH79NZ029 sensor/10HB50106802 well (4-in. sensor/well)

Fig. 17 — Dual Chiller Thermistor Location

started to maintain lubrication to the pump seal. To utilize this
function, Cooler Pmp Periodic Start (PM.P.S) [Configuration,
UNIT] must be se t to YES. This option i s se t to N O a s th e f a c­tory default. If feature is enabled and the pump(s) are not
operating, then the pumps will be operated every other day for
2 seconds starting at 14:00 hours. If a pump has failed and has
an active Alert condition, it will not be started that day .

Configuring and Operating Dual Chiller Con­trol —

two units supplying chilled fluid on a common loop. This
control algorithm is designed for parallel fluid flow arrangement
only. One chiller must be configured as the master chiller, the
other as the slave. An additional leaving fluid temperature
thermistor (Dual Chiller LWT) must be installed as shown in
Fig. 17 and connected to the master chiller. Refer to Sensors sec­tion, page 4, for wiring. The SCN communication bus must be
connected between the two chillers. Connections can be made
to the SCN screw terminals on TB3. Refer to Sterlco Comfort
Network Interface section, page 3, for wiring inf ormation.

example the master chiller will be confi gured at address 1 and
the slave chiller at address 2. The master and slave chillers
must reside on the same SCN bus (SCNB) but cannot have the
same SCN address (SCNA) [Configuration, OPT2]. Both
master and slave chillers must have Lead/Lag Chiller Enable
(LLEN) [Configuration, RSET] configured to ENBL. Master/
Slave Select (MSSL) [Configuration, RSET] must be config­ured to MAST for the mast er chiller and SLVE for the slave.
Also in this example, the m aster chiller will be configured t o
use Lead/Lag Balance Select (LLBL ) and Lead/Lag Balance
Delta (LLBD) [Configuration, RSET] to even out the chiller
run-times weekly. The Lag Start Delay (LLDY) [Configura­tion, RSET] feature will be set to 10 minutes. This will prevent
the lag chil ler from starting u ntil the lead ch iller has been at
100% capacity for the length of the delay time. Parallel config­uration (PARA) [Configuration, RSET] can only be config­ured to YES. The variables LLBL, LLBD and LLDY are not
used by the slave chiller.

SUB-MODE

Ckt — Circuit

*Throughout this text, the location of items in the menu structure will be

described in the following format:
Item Expansion (ITEM) [Mode Name, Sub-mode Name]

The dual chiller routine is available for the control of

Refer to Table 21 for dual chiller configuration. In this

Table 9 — Marquee Display Menu Structure*

MODE

LEGEND

RUN

STATUS

Auto
Display
(VIEW)

Machine

Hours/Starts

(RUN)

Compressor

Run Hours

(HOUR)

Compressor

Starts

(STRT)

Pump Maint.

(PM)

Software

Ver si on
(VERS)

SERVICE

TEST

Manual

Mode

On/Off

(TEST)

Unit
Outputs
(OUTS)

Ckt A Comp

Tests

(CMPA)

Ckt B Comp

Tests

(CMPB)

TEMPERATURES PRESSURES

Unit

Temperatures

(UNIT)

Ckt A

Temperatures

(CIR.A)

Ckt B

Temperatures

(CIR.B)

Ckt A

Pressures

(PRC.A)

Ckt B

Pressures

(PRC.B)

SET

POINTS

Cooling
(COOL)

Head

Pressure

(HEAD)

Brine

Freeze-

point

(FRZ)

Dual chiller start/stop control is determined by configura­tion of Control Method (CTRL) [Configuration, OPT2] of the
Master chiller. The Slave chiller should always be configured
for CTRL=0, Switch. If the chillers are to be controlled by
Remote Contacts, both Master and Slave chillers should be
enabled together. Two separate relays or one relay with
two sets of contacts may control the chiller s. The Enable/Off/
Remote Contact switch should be in the Remote Contact
position on both the Master and Slave chillers. The Enable/Off/
Remote Contact switch should be in the Enable position for
CTRL=2, Occupancy or CTRL=3, SCN Control.

Both chillers will stop if the Master chiller Enable/Off/
Remote Contact switch is in the Off position. If the Emergency
Stop switch is turned off or an alarm is generated on the Master
chiller the Slave chiller will opera te in a Stand-Alone mode.
If the Emergency Stop switch is turned off or an alarm is
generated on the Slave chille r th e M a ste r c h il ler will operate in
a Stand-Alone mode.

The master chiller controls the sla ve chiller by changi ng its
Control Mode (STAT) [Run Status, VIEW] and its operating
setpoint or Control Point (CTPT) [Run Status, VIEW].

THERMISTOR
WIRING*

MODES

Modes

(MODE)

LEAVING
FLUID

ALARMS

Current
(CRNT)

Alarms

(RCRN)

History

Reset

Alarm

(HIST)

RETURN
FLUID

INPUTS OUTPUTS CONFIGURATION

Unit

Discrete

(GEN.I)

Ckt A/B
(CRCT)

Unit

Analog

(4-20)

For example, using the language selection item:
Language Selection (LANG) [Configuration, DISP]

Unit

Discrete

(GEN.O)

Ckt A

(CIR.A)

Ckt B

(CIR.B)

MASTER

CHILLER

SLAVE

CHILLER

Display

(DISP)

Machine

(UNIT)

Options 1

(OPT1)

Options 2

(OPT2)

Temperature

Reset

(RSET)

Set Point

Select

(SLCT)
Service

Configuration

(SERV)

Broadcast

Configuration

(BCST)

INSTALL DUAL CHILLER LWT
LEAVING FLUID TEMPERATURE
THERMISTOR (T10) HERE

TIME

CLOCK

Unit Time

(TIME)

Unit Date

(DATE)

Daylight

Saving

Time

(DST)

Schedule

Number

(SCH.N)

Local

Schedule

(SCH.L)

Schedule

Override

(OVR)

OPERATING

26

Table 10 — Run Status Mode and Sub-Mode Directory

SUB-MODE

VIEW EWT

KEYPAD

ENTRY

ENTER

ITEM DISPLAY SUB-ITEM DISPLAY SUB-ITEM DISPLAY

XXX.X °F

LWT

XXX.X °F

SETP

XXX.X °F

CTPT

XXX.X °F

ENTERING FLUID TEMP

ITEM

EXPANSION

LEAVING FLUID TEMP

ACTIVE SETPOINT

CONTROL POINT

COMMENT

LOD.F XXX LOAD/UNLOAD FACTOR

STAT X CONTROL MODE 0 = Service Test

1 = Off Local
2 = Off SCN
3 = Off Time
4 = Off Emrgcy
5 = On Local
6 = On SCN
7 = On Time
8 = Ht Enabled
9 = Pump Delay

LD.PM LEAD PUMP

OCC YES/NO OCCUPIED

LS.AC YES/NO LOW SOUND ACTIVE

MODE YES/NO OVERRIDE MODES IN EFFECT

CAP XXX % PERCENT TOTAL CAPACITY

STGE X REQUESTED STAGE

ALRM XXX CURRENT ALARMS & ALERTS

TIME XX.XX TIME OF DAY 00.00-23.59

MNTH XX MONTH OF YEAR 1 = January, 2 = February, etc.

DATE XX DAY OF MONTH 01-31

YEAR XX YEAR OF THE CENTURY

RUN HRS.U XXXX HRS MACHINE OPERATING HOURS

ENTER

STR.U XXXX MACHINE STARTS

HR.P1 XXXX.X PUMP 1 RUN HOURS

HR.P2 XXXX.X PUMP 2 RUN HOURS

HOUR HRS.A XXXX HRS CIRCUIT A RUN HOURS

ENTER

HRS.B XXXX HRS CIRCUIT B RUN HOURS See Note

HR.A1 XXXX HRS COMPRESSOR A1 RUN HOURS

HR.A2 XXXX HRS COMPRESSOR A2 RUN HOURS

HR.B1 XXXX HRS COMPRESSOR B1 RUN HOURS See Note

HR.B2 XXXX HRS COMPRESSOR B2 RUN HOURS See Note

STRT ST.A1 XXXX COMPRESSOR A1 STARTS

ENTER

ST.A2 XXXX COMPRESSOR A2 STARTS

ST.B1 XXXX COMPRESSOR B1 STARTS See Note

ST.B2 XXXX COMPRESSOR B2 STARTS See Note

PM PUMP PUMP MAINTENANCE

ENTER

ENTER

SI.PM XXXX HRS PUMP SERVICE INTERVAL

P.1.DN XXXX HRS PUMP 1 SERVICE COUNTDOWN

P.2.DN XXXX HRS PUMP 2 SERVICE COUNTDOWN

P.1.MN YES/NO PUMP 1 MAINTENANCE DONE User Entry

P.2.MN YES/NO PUMP 2 MAINTENANCE DONE User Entry

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

27

Table 10 — Run Status Mode and Sub-Mode Directory (cont)

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY SUB-ITEM DISPLAY SUB-ITEM DISPLAY

ITEM

EXPANSION

PM (cont) PMDT PUMP MAINTENANCE DATES

ENTER

P.1.M0 MM/DD/YY HH:MM

P.1.M1 MM/DD/YY HH:MM

P.1.M2 MM/DD/YY HH:MM

P.1.M3 MM/DD/YY HH:MM

P.1.M4 MM/DD/YY HH:MM

P.2.M0 MM/DD/YY HH:MM

P.2.M1 MM/DD/YY HH:MM

P.2.M2 MM/DD/YY HH:MM

P.2.M3 MM/DD/YY HH:MM

P.2.M4 MM/DD/YY HH:MM

ENTER

STRN STRAINER MAINTENANCE

ENTER

SI.ST XXXX HRS STRAINER SRVC INTERVAL

S.T.DN XXXX HRS STRAINER SRVC COUNTDOWN

S.T.MN YES/NO STRAINER MAINT. DONE User Entry

ST.DT STRAINER MAINT. DATES

ENTER

S.T.M0 MM/DD/YY HH:MM

COMMENT

S.T.M1 MM/DD/YY HH:MM

S.T.M2 MM/DD/YY HH:MM

S.T.M3 MM/DD/YY HH:MM

S.T.M4 MM/DD/YY HH:MM

ENTER

COIL COIL MAINTENANCE

ENTER

SI.CL XXXX HRS COIL SRVC INTER

C.L.DN XXXX HRS COIL SERVICE COUNTDOWN

C.L.MN YES/NO COIL MAINT. DONE User Entry

CL.DT COIL MAINTENANCE DATES

ENTER

C.L.M0 MM/DD/YY HH:MM

C.L.M1 MM/DD/YY HH:MM

C.L.M2 MM/DD/YY HH:MM

C.L.M3 MM/DD/YY HH:MM

C.L.M4 MM/DD/YY HH:MM

VERS MBB CESR-131279-xx-xx xx-xx is Version number*

ENTER

MARQ CESR-131171-xx-xx xx-xx is Version number*

EMM CESR-131174-xx-xx xx-xx is Version number*

NAVI CESR-131227-xx-xx xx-xx is Version number*

*Press and simultaneously to obtain version number.

ENTER ESCAPE

28

Table 11 — Service Test Mode and Sub-Mode Directory

SUB-MODE

TEST ON/OFF SERVICE TEST MODE To Enable Service Test Mode,

KEYPAD

ENTRY

ENTER

ITEM DISPLAY

ITEM

EXPANSION

COMMENT

move Enable/Off/Remote
Contact switch to OFF. Change
TEST to ON. Move switch to
ENABLE.

OUTS OUTPUTS AND PUMPS

ENTER

FAN1 ON/OFF FAN 1 RELAY

FAN2 ON/OFF FAN 2 RELAY

CLP.1 ON/OFF COOLER PUMP 1 RELAY

CLP.2 ON/OFF COOLER PUMP 2 RELAY

CL.HT ON/OFF COOLER/PUMP HEATER

RMT.A ON/OFF REMOTE ALARM RELAY

CMPA CIRCUIT A COMPRESSOR TEST

ENTER

CC.A1 ON/OFF COMPRESSOR A1 RELAY

CC.A2 ON/OFF COMPRESSOR A2 RELAY

MLV ON/OFF MINIMUM LOAD VALVE RELAY

CMPB CIRCUIT B COMPRESSOR TEST See Note

ENTER

CC.B1 ON/OFF COMPRESSOR B1 RELAY

CC.B2 ON/OFF COMPRESSOR B2 RELAY

MLV ON/OFF MINIMUM LOAD VALVE RELAY

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

Table 12 — Temperature Mode and Sub-Mode Directory

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

UNIT ENT AND LEAVE UNIT TEMPS

ENTER

CEWT

CLWT

OAT

SPT

DLWT

XXX.X °F

XXX.X °F

XXX.X °F

XXX.X °F

XXX.X °F

COOLER ENTERING FLUID

COOLER LEAVING FLUID

OUTSIDE AIR TEMPERATURE

LEAD/LAG LEAVING FLUID

CIR.A TEMPERATURES CIRCUIT A

ENTER

SCT.A

SST.A

RGT.A

XXX.X °F

XXX.X °F

XXX.X °F

SATURATED CONDENSING TMP

SATURATED SUCTION TEMP

COMPR RETURN GAS TEMP

SH.A XXX.X ^F SUCTION SUPERHEAT TEMP

CIR.B TEMPERATURES CIRCUIT B See Note

ENTER

SCT.B

SST.B

RGT.B

XXX.X °F

XXX.X °F

XXX.X °F

SATURATED CONDENSING TMP See Note

SATURATED SUCTION TEMP See Note

COMPR RETURN GAS TEMP See Note

SH.B XXX.X ^F SUCTION SUPERHEAT TEMP See Note

ITEM

EXPANSION

SPACE TEMPERATURE

COMMENT

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

29

Table 13 — Pressure Mode and Sub-Mode Directory

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

PRC.A PRESSURES CIRCUIT A

ENTER

DP.A XXX.X PSIG DISCHARGE PRESSURE

SP.A XXX.X PSIG SUCTION PRESSURE

PRC.B PRESSURES CIRCUIT B See Note

ENTER

DP.B XXX.X PSIG DISCHARGE PRESSURE See Note

SP.B XXX.X PSIG SUCTION PRESSURE See Note

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

ITEM

EXPANSION

Table 14 — Set Point and Sub-Mode Directory

COMMENT

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

ITEM

EXPANSION

COOL COOLING SETPOINTS

ENTER

CSP.1

CSP.2

CSP.3

XXX.X °F

XXX.X °F

XXX.X °F

COOLING SETPOINT 1 Default: 44 F

COOLING SETPOINT 2 Default: 44 F

ICE SETPOINT Default: 32 F

HEAD HEAD PRESSURE SETPOINTS

ENTER

HD.P.A

HD.P.B

XXX.X °F

XXX.X °F

CALCULATED HP SETPOINT A

CALCULATED HP SETPOINT B

FRZ BRINE FREEZE SETPOINT

ENTER

BR.FZ

XXX.X °F

BRINE FREEZE POINT Default: 34 F

Table 15 — Inputs Mode and Sub-Mode Directory

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

GEN.I GENERAL INPUTS

ENTER

STST STRT/STOP START/STOP SWITCH

FLOW ON/OFF COOLER FLOW SWITCH

PM.F.1 OPEN/CLSE COOLER PUMP 1 INTERLOCK

LD.PM X Lead Pump

PM.F.2 OPEN/CLSE COOLER PUMP 2 INTERLOCK

ITEM

EXPANSION

COMMENT

Default: 113 F

(Read Only)

Default: 113 F

(Read Only)

COMMENT

1 = Pump 1
2 = Pump 2
3 = No Pump

HT.RQ ON/OFF HEAT REQUEST

DLS1 ON/OFF DEMAND LIMIT SWITCH 1

DLS2 ON/OFF DEMAND LIMIT SWITCH 2

ICED ON/OFF ICE DONE

DUAL ON/OFF DUAL SETPOINT SWITCH

CRCT CIRCUITS INPUTS

ENTER

FKA1 ON/OFF COMPRESSOR A1 FEEDBACK

FKA2 ON/OFF COMPRESSOR A2 FEEDBACK

FKB1 ON/OFF COMPRESSOR B1 FEEDBACK See Note

FKB2 ON/OFF COMPRESSOR B2 FEEDBACK See Note

4-20 4-20 MA INPUTS

ENTER

DMND XX.X MA 4-20 MA DEMAND SIGNAL

RSET XX.X MA 4-20 MA RESET SIGNAL

CSP XX.X MA 4-20 MA COOLING SETPOINT

30

Table 16 — Outputs Mode and Sub-Mode Directory

SUB-MODE

GEN.O

CIR.A

CIR.B

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ITEM DISPLAY

FAN1 ON/OFF FAN 1 RELAY

FAN2 ON/OFF FAN 2 RELAY

C.WP1 ON/OFF COOLER PUMP RELAY 1

C.WP2 ON/OFF COOLER PUMP RELAY 2

CLHT ON/OFF COOLER/PUMP HEATER

MLV.R ON/OFF MINIMUM LOAD VALVE RELAY

CC.A1 ON/OFF COMPRESSOR A1 RELAY

CC.A2 ON/OFF COMPRESSOR A2 RELAY

CC.B1 ON/OFF COMPRESSOR B1 RELAY

CC.B2 ON/OFF COMPRESSOR B2 RELAY

ITEM

EXPANSION

GENERAL OUTPUTS

OUTPUTS CIRCUIT A

OUTPUTS CIRCUIT B See Note

Table 17 — Configuration Mode and Sub-Mode Directory

SUB-MODE

DISP

UNIT

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

KEYPAD

ENTRY

ENTER

ENTER

ITEM DISPLAY

DISPLAY CONFIGURATION

TEST ON/OFF TEST DISPLAY LEDS

METR ON/OFF METRIC DISPLAY Off = English; On = Metric

LANG X LANGUAGE SELECTION Default: 0

PAS.E ENBL/DSBL PASSWORD ENABLE

PASS xxxx SERVICE PASSWORD

UNIT CONFIGURATION

SZA.1 XX COMPRESSOR A1 SIZE

SZA.2 XX COMPRESSOR A2 SIZE

SZB.1 XX COMPRESSOR B1 SIZE

SZB.2 X X COMPRESSOR B2 SIZE

SH.SP

REFG X REFRIGERANT 1 = R-22

FAN.S FAN STAGING SELECT 1 = One Fan (010-018)

XX.X ∆F

ITEM

EXPANSION

SUPERHEAT SETPOINT

COMMENT

COMMENT

0 = English
1 = Espanol
2 = Francais
3 = Portuguese

Unit Size 60 Hz 50 Hz

010
015
018
022
025
030
032
035
040
042
045
050
055

Unit Size 60 Hz 50 Hz

015
018
022
025
030
032
035
040
042
045
050
055

Unit Size 60 Hz 50 Hz

032
035
040
042
045
050
055

Unit Size 60 Hz 50 Hz

042
045
050
055

2 = Two Fans (022-030)
3 = Three Fans (032-040)
4 = Four Fans (042-055)

10
15

9

9
13
15

—

9
13

—

10
13
15

—

9
13
13
15

—

13
13

—

13
13
15

—

15
15

—

10
13
15

—

13
13
15

Default: 15 °F

11

11
13

—

13

—

11
13

—
—

11
13

—

11
13

—

11
13

—
—

13
13

—

11
13

—
—

11
13

—
—

7
9

8

7
9

31

SUB-MODE

OPT1

OPT2

RSET

Table 17 — Configuration Mode and Sub-Mode Directory (cont)

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ITEM DISPLAY

UNIT OPTIONS 1 HARDWARE

FLUD X COOLER FLUID Default: Water

MLV.S YES/NO MINIMUM LOAD VALVE SELECT

MMR.S YES/NO MOTORMASTER SELECT

RG.EN ENBL/DSBL RETURN GAS SENSOR ENABLE Default: DISABLED

CPC ON/OFF COOLER PUMP CONTROL Default: On

PM1E YES/NO COOLER PUMP 1 ENABLE

PM2E YES/NO COOLER PUMP 2 ENABLE

PM.P.S YES/NO COOLER PMP PERIODIC STRT Default: No

PM.SL X COOLER PUMP SELECT Default: Automatic

PM.DY XX MIN COOLER PUMP SHUTDOWN DLY 0 to 10 minutes, Default: 1 min.

PM.DT XXXX HRS PUMP CHANGEOVER HOURS Default: 500 hours

ROT.P YES/NO ROTATE COOLER PUMPS NOW User Entry

EMM YES/NO EMM MODULE INSTALLED

UNIT OPTIONS 2 CONTROLS

CTRL X CONTROL METHOD Default: Switch

SCNA XXX SCN ADDRESS

SCNB XXX SCN BUS NUMBER

BAUD X SCN BAUD RATE Default: 9600

LOAD X LOADING SEQUENCE SELECT Default: Equal

LLCS X LEAD/LAG CIRCUIT SELECT Default: Automatic

LCWT

XX.X ∆F

DELY XX MINUTES OFF TIME

ICE.M ENBL/DSBL ICE MODE ENABLE Default: Disable

CLS.C ENBL/DSBL CLOSE CONTROL SELECT Default: Disable

LS.MD X LOW SOUND MODE SELECT Default: 0

LS.ST 00:00 LOW SOUND START TIME Default: 00:00

LS.ND 00:00 LOW SOUND END TIME Default: 00:00

LS.LT XXX % LOW SOUND CAPACITY LIMIT

CRST X COOLING RESET TYPE Default: No Reset

MA.DG

RM.NO

XX.X ∆F

XXX.X °F

REMOTE - NO RESET TEMP

ITEM

EXPANSION

HIGH LCW ALERT LIMIT

RESET COOL TEMP

4-20 - DEGREES RESET

COMMENT

1 = Water
2 = Medium Temperature Brine

0 = Automatic
1 = Pump 1 Starts first
2 = Pump 2 Starts first

0 = Enable/Off/Remote Switch
2 = Occupancy
3 = SCN Control

Default: 1

Range: 1 to 239

Default: 0

Range: 0 to 239

1 = 2400
2 = 4800
3 = 9600
4 = 19,200
5 = 38,400

1 = Equal
2 = Staged

1 = Automatic
2 = Circuit A Leads
3 = Circuit B Leads

Default: 60
Range: 2 to 60 °F

Default: 0 Minutes
Range: 0 to 15 Minutes

0 = Mode Disable
1 = Fan Noise Only
2 = Fan/Compressor Noise

Default: 100%
Range: 0 to 100%

0 = No Reset
1 = 4 to 20 mA Input
2 = Outdoor Air Temperature
3 = Return Fluid
4 = Space Temperature

Default: 0.0 ∆F
Range: –30 to 30 ∆F

Default: 125 F (51.7 C)
Range: 0° to 125 F

32

SUB-MODE

RSET (cont)

SLCT

SERV

BCST

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ENTER

Table 17 — Configuration Mode and Sub-Mode Directory (cont)

ITEM DISPLAY

RM.F

RM.DG

RT.NO

RT.F

RT.DG

XXX.X °F

XX.X °F

XXX.X ∆F

XXX.X ∆F

XX.X °F

REMOTE - FULL RESET TEMP

REMOTE - DEGREES RESET

RETURN - NO RESET TEMP

RETURN - FULL RESET TEMP

RETURN - DEGREES RESET

DMDC X DEMAND LIMIT SELECT Default: None

DM20 XXX % DEMAND LIMIT AT 20 MA

SHNM XXX LOADSHED GROUP NUMBER

SHDL XXX % LOADSHED DEMAND DELTA

SHTM XXX MAXIMUM LOADSHED TIME

DLS1 XXX % DEMAND LIMIT SWITCH 1

DLS2 XXX % DEMAND LIMIT SWITCH 2

LLEN ENBL/DSBL LEAD/LAG CHILLER ENABLE Default: Disable

MSSL SLVE/MAST MASTER/SLAVE SELECT Default: Master

SLVA XXX SLAVE ADDRESS

LLBL X LEAD/LAG BALANCE SELECT Default: Master Leads

LLBD XXX LEAD/LAG BALANCE DELTA

LLDY XXX LAG START DELAY

PARA YES PARALLEL CONFIGURATION Default: YES (CANNOT BE CHANGED)

SETPOINT AND RAMP LOAD

CLSP X COOLING SETPOINT SELECT Default: Single

RL.S ENBL/DSBL RAMP LOAD SELECT Default: Enable

CRMP X.X COOLING RAMP LOADING

SCHD XX SCHEDULE NUMBER

Z.GN X.X DEADBAND MULTIPLIER

SERVICE CONFIGURATION

EN.A1 ENBL/DSBL ENABLE COMPRESSOR A1 Unit dependent

EN.A2 ENBL/DSBL ENABLE COMPRESSOR A2 Unit dependent

EN.B1 ENBL/DSBL ENABLE COMPRESSOR B1 Unit dependent

EN.B2 ENBL/DSBL ENABLE COMPRESSOR B2 Unit dependent

BROADCAST CONFIGURATION

T.D.BC ON/OFF SCN TIME/DATE BROADCAST

OAT.B ON/OFF SCN OAT BROADCAST

G.S.BC ON/OFF GLOBAL SCHEDULE BROADCAST

BC.AK ON/OFF SCN BROADCAST ACK’ER

ITEM

EXPANSION

COMMENT

Default: 0.0° F (-17.8 C)
Range: 0° to 125 F

Default: 0.0° F
Range: –30 to 30 F

Default: 10.0 ∆F (5.6 ∆C)
Range: 0° to 125 F COOLER ∆T

Default: 0.0 ∆F (0.0 ∆C)
Range: 0° to 125 F COOLER ∆T

Default: 0.0° F
Range: –30 to 30 F

0 = None
1 = Switch
2 = 4 to 20 mA Input
3 = SCN Loadshed

Default: 100%
Range: 0 to 100%

Default: 0
Range: 0 to 99

Default: 0%
Range: 0 to 60%

Default: 60 minutes
Range: 0 to 120 minutes

Default: 80%
Range: 0 to 100%

Default: 50%
Range: 0 to 100%

Default: 2
Range: 0 to 239

0 = Master Leads
1 = Slave Leads
2 = Automatic

Default: 168 hours
Range: 40 to 400 hours

Default: 5 minutes
Range: 0 to 30 minutes

0 = Single
1 = Dual Switch
2 = Dual SCN Occupied
3 = 4 to 20 mA Input (requires

EMM)

Default: 1.0
Range: 0.2 to 2.0

Default: 1
Range: 1 to 99

Default: 2.0
Range: 1.0 to 4.0

(–34.4 to -1.1 C)

33

Table 18 — Time Clock Mode and Sub-Mode Directory

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY SUB-ITEM DISPLAY

ITEM

EXPANSION

COMMENT

TIME TIME OF DAY

ENTER

HH.MM XX.XX HOUR AND MINUTE Military (00:00 – 23:59)

DATE MONTH,DATE,DAY AND YEAR

ENTER

MNTH XX MONTH OF YEAR 1-12 (1 = January, 2 = February, etc)

DOM XX DAY OF MONTH Range: 01-31

DAY X DAY OF WEEK 1-7 (1 = Sunday, 2 = Monday, etc)

YEAR XXXX YEAR OF CENTURY

DST DAYLIGHT SAVINGS TIME

ENTER

STR.M XX MONTH Default: 4, Range 1 – 12

STR.W X WEEK Default: 1, Range 1 – 5

STR.D X DAY Default: 7, Range 1 – 7

MIN.A XX MINUTES TO ADD Default: 60, Range 0 – 99

STP.M XX MONTH Default: 10, Range 1 – 12

STP.W XX WEEK Default: 5, Range 1 – 5

STP.D XX DAY Default: 7, Range 1 – 7

MIN.5 XX MINUTES TO SUBTRACT Default: 60, Range 0 – 99

SCH.N XX SCHEDULE NUMBER Default: 1, Range 1 – 99

SCH.L LOCAL OCCUPANCY SCHEDULE

ENTER

ENTER

PER.1 OCCUPANCY PERIOD 1

OCC.1 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.1 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

ENTER

ENTER

MON.1 YES/NO MONDAY IN PERIOD

TUE.1 YES/NO TUESDAY IN PERIOD

WED.1 YES/NO WEDNESDAY IN PERIOD

THU.1 YES/NO THURSDAY IN PERIOD

FRI.1 YES/NO FRIDAY IN PERIOD

SAT.1 YES/NO SATURDAY IN PERIOD

SUN.1 YES/NO SUNDAY IN PERIOD

HOL.1 YES/NO HOLIDAY IN PERIOD

PER.2 OCCUPANCY PERIOD 2

OCC.2 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.2 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.2 YES/NO MONDAY IN PERIOD

TUE.2 YES/NO TUESDAY IN PERIOD

WED.2 YES/NO WEDNESDAY IN PERIOD

THU.2 YES/NO THURSDAY IN PERIOD

FRI.2 YES/NO FRIDAY IN PERIOD

SAT.2 YES/NO SATURDAY IN PERIOD

SUN.2 YES/NO SUNDAY IN PERIOD

HOL.2 YES/NO HOLIDAY IN PERIOD

34

Table 18 — Time Clock Mode and Sub-Mode Directory (cont)

SUB-MODE

SCH.L (cont) PER.3 OCCUPANCY PERIOD 3

KEYPAD

ENTRY

ENTER

ENTER

ITEM DISPLAY SUB-ITEM DISPLAY

OCC.3 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

ITEM

EXPANSION

UNC.3 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.3 YES/NO MONDAY IN PERIOD

TUE.3 YES/NO TUESDAY IN PERIOD

WED.3 YES/NO WEDNESDAY IN PERIOD

THU.3 YES/NO THURSDAY IN PERIOD

FRI.3 YES/NO FRIDAY IN PERIOD

SAT.3 YES/NO SATURDAY IN PERIOD

SUN.3 YES/NO SUNDAY IN PERIOD

HOL.3 YES/NO HOLIDAY IN PERIOD

ENTER

ENTER

PER.4 OCCUPANCY PERIOD 4

OCC.4 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.4 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.4 YES/NO MONDAY IN PERIOD

TUE.4 YES/NO TUESDAY IN PERIOD

WED.4 YES/NO WEDNESDAY IN PERIOD

COMMENT

ENTER

ENTER

ENTER

ENTER

THU.4 YES/NO THURSDAY IN PERIOD

FRI.4 YES/NO FRIDAY IN PERIOD

SAT.4 YES/NO SATURDAY IN PERIOD

SUN.4 YES/NO SUNDAY IN PERIOD

HOL.4 YES/NO HOLIDAY IN PERIOD

PER.5 OCCUPANCY PERIOD 5

OCC.5 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.5 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.5 YES/NO MONDAY IN PERIOD

TUE.5 YES/NO TUESDAY IN PERIOD

WED.5 YES/NO WEDNESDAY IN PERIOD

THU.5 YES/NO THURSDAY IN PERIOD

FRI.5 YES/NO FRIDAY IN PERIOD

SAT.5 YES/NO SATURDAY IN PERIOD

SUN.5 YES/NO SUNDAY IN PERIOD

HOL.5 YES/NO HOLIDAY IN PERIOD

PER.6 OCCUPANCY PERIOD 6

OCC.6 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.6 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.6 YES/NO MONDAY IN PERIOD

TUE.6 YES/NO TUESDAY IN PERIOD

WED.6 YES/NO WEDNESDAY IN PERIOD

35

Table 18 — Time Clock Mode and Sub-Mode Directory (cont)

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY SUB-ITEM DISPLAY

ITEM

EXPANSION

SCH.L (cont) THU.6 YES/NO THURSDAY IN PERIOD

FRI.6 YES/NO FRIDAY IN PERIOD

SAT.6 YES/NO SATURDAY IN PERIOD

SUN.6 YES/NO SUNDAY IN PERIOD

HOL.6 YES/NO HOLIDAY IN PERIOD

ENTER

ENTER

PER.7 OCCUPANCY PERIOD 7

OCC.7 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.7 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.7 YES/NO MONDAY IN PERIOD

TUE.7 YES/NO TUESDAY IN PERIOD

WED.7 YES/NO WEDNESDAY IN PERIOD

THU.7 YES/NO THURSDAY IN PERIOD

FRI.7 YES/NO FRIDAY IN PERIOD

SAT.7 YES/NO SATURDAY IN PERIOD

SUN.7 YES/NO SUNDAY IN PERIOD

HOL.7 YES/NO HOLIDAY IN PERIOD

ENTER

PER.8 OCCUPANCY PERIOD 8

COMMENT

ENTER

OCC.8 XX:XX PERIOD OCCUPIED TIME Military (00:00 – 23:59)

UNC.8 XX.XX PERIOD UNOCCUPIED TIME Military (00:00 – 23:59)

MON.8 YES/NO MONDAY IN PERIOD

TUE.8 YES/NO TUESDAY IN PERIOD

WED.8 YES/NO WEDNESDAY IN PERIOD

THU.8 YES/NO THURSDAY IN PERIOD

FRI.8 YES/NO FRIDAY IN PERIOD

SAT.8 YES/NO SATURDAY IN PERIOD

SUN.8 YES/NO SUNDAY IN PERIOD

HOL.8 YES/NO HOLIDAY IN PERIOD

OVR SCHEDULE OVERRIDE

ENTER

OVR.T X TIMED OVERRIDE HOURS Default: 0, Range 0-4 hours

OVR.L X OVERRIDE TIME LIMIT Default: 0, Range 0-4 hours

T.OVR YES/NO TIMED OVERRIDE User Entry

36

Table 19 — Operating Mode and Sub-Mode Directory

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

ITEM

EXPANSION

MODE MODES CONTROLLING UNIT

ENTER

MD01 ON/OFF FSM CONTROLLING CHILLER

MD02 ON/OFF WSM CONTROLLING CHILLER

MD03 ON/OFF MASTER/SLAVE CONTROL

MD05 ON/OFF RAMP LOAD LIMITED

MD06 ON/OFF TIMED OVERRIDE IN EFFECT

MD07 ON/OFF LOW COOLER SUCTION TEMPA

MD08 ON/OFF LOW COOLER SUCTION TEMPB

MD09 ON/OFF SLOW CHANGE OVERRIDE

MD10 ON/OFF MINIMUM OFF TIME ACTIVE

MD13 ON/OFF DUAL SETPOINT

MD14 ON/OFF TEMPERATURE RESET

MD15 ON/OFF DEMAND/SOUND LIMITED

MD16 ON/OFF COOLER FREEZE PROTECTION

MD17 ON/OFF LOW TEMPERATURE COOLING

MD18 ON/OFF HIGH TEMPERATURE COOLING

MD19 ON/OFF MAKING ICE

COMMENT

MD20 ON/OFF STORING ICE

MD21 ON/OFF HIGH SCT CIRCUIT A

MD22 ON/OFF HIGH SCT CIRCUIT B

MD23 ON/OFF MINIMUM COMP ON TIME

MD24 ON/OFF PUMP OFF DELAY TIME

MD25 ON/OFF LOW SOUND MODE

MD26 ON/OFF SHORT LOOP OVERRIDE

LEGEND

FSM — Flotronic™ System Manager
SCT — Saturated Condensing Temperature
WSM — Water System Manager

Table 20 — Alarms Mode and Sub-Mode Directory

SUB-MODE

CRNT AXXX OR TXXX CURRENTLY ACTIVE ALARMS

RCRN YES/NO RESET ALL CURRENT ALARMS

HIST AXXX OR TXXX ALARM HISTORY

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ITEM

ITEM

EXPANSION

COMMENT

Alarms are shown as AXXX.
Alerts are shown as TXXX.

Alarms are shown as AXXX.
Alerts are shown as TXXX.

37

Table 21 — Dual Chiller Configuration (Master Chiller Example)

SUB-MODE ITEM KEYPAD ENTRY DISPLAY ITEM EXPANSION COMMENTS

DISP

UNIT

OPT1

OPT2 CTRL CONTROL METHOD

CTRL 0 SWITCH DEFAULT 0

SCNA 1 SCN ADDRESS DEFAULT 1

ENTER

ENTER

ESCAPE

ENTER

ENTER

ESCAPE

CTRL

SCNA

SCNA

SCNB

SCNB 0 SCN BUS NUMBER DEFAULT 0

ENTER

ESCAPE

ESCAPE

SCNB

OPT2

RSET

RSET CRST COOLING RESET TYPE

ENTER

LLEN LEAD/LAG CHILLER ENABLE 15 ITEMS

LLEN DSBL SCROLLING STOPS

ENTER

ENTER

DSBL VALUE FLASHES

PROCEED TO

SUBMODE RESET

ENBL SELECT ENBL

LLEN ENBL LEAD/LAG CHILLER ENABLE CHANGE ACCEPTED

ENTER

ESCAPE

LLEN

MSSL MASTER /SLAVE SELECT

MSSL MAST MASTER /SLAVE SELECT DEFAULT MAST

ENTER

ESCAPE

MSSL

SLVA SLAVE ADDRESS

SLVA 0 SCROLLING STOPS

ENTER

ENTER

0 VALUE FLASHES

2SELECT 2

SLVA 2 SLAVE ADDRESS CHANGE ACCEPTED

ENTER

ESCAPE

SLVA

LLBL LEAD/LAG BALANCE SELECT

LLBL 0 SCROLLING STOPS

ENTER

ENTER

0 VALUE FLASHES

2 SELECT 2 - Automatic

38

Table 21 — Dual Chiller Configuration (Master Chiller Example) (cont)

SUB-MODE ITEM KEYPAD ENTRY DISPLAY ITEM EXPANSION COMMENTS

RSET

LLBL 2 LEAD/LAG BALANCE SELECT CHANGE ACCEPTED

ENTER

ESCAPE

LLBL

LLBD LEAD/LAG BALANCE DELTA

LLBD 168 LEAD/LAG BALANCE DELTA DEFAULT 168

ENTER

ESCAPE

LLBD

LLDY LAG START DELAY

LLDY 5 SCROLLING STOPS

ENTER

ENTER

5 VALUE FLASHES

10 SELECT 10

LLDY 10 LAG START DELAY CHANGE ACCEPTED

PARA YES MASTER COMPLETE

NOTES:

1. Master Control Method (CTRL) can be configured as 0-Switch, 2-Occupancy or 3-SCN.

2. Parallel Configuration (PARA) cannot be changed.

ENTER

ESCAPE

ESCAPE

ENTER

LLDY

RSET

39

Tabl e 22 — Dual Chiller Configuration (Slave Chiller Example)

SUB-MODE ITEM KEYPAD ENTRY DISPLAY ITEM EXPANSION COMMENTS

DISP

UNIT

OPT1

OPT2 CTRL CONTROL METHOD

ENTER

CTRL 0 SWITCH DEFAULT 0

ESCAPE

CTRL

CTRL SCNA

SCNA 1 SCN ADDRESS SCROLLING STOPS

ENTER

ENTER

1 VALUE FLASHES

2

SCNA 2 SCN ADDRESS CHANGE ACCEPTED

ENTER

ESCAPE

SCNA

SCNB

SCNB 0 SCN BUS NUMBER

ENTER

ESCAPE

ESCAPE

SCNB

OPT2

RSET

RSET CRST COOLING RESET TYPE

ENTER

SELECT 2

(SEE NOTE 1)

DEFAULT 0

(SEE NOTE 2)

PROCEED TO

SUBMODE RSET

LLEN LEAD/LAG CHILLER ENABLE 15 ITEMS

LLEN DSBL SCROLLING STOPS

ENTER

ENTER

DSBL VALUE FLASHES

ENBL SELECT ENBL

LLEN ENBL LEAD/LAG CHILLER ENABLE CHANGE ACCEPTED

ENTER

ESCAPE

LLEN

MSSL MASTER /SLAVE SELECT

MSSL MAST SCROLLING STOPS

ENTER

ENTER

MAST VALUE FLASHES

SLVE SELECT SLVE

MSSL SLVE MASTER /SLAVE SELECT CHANGE ACCEPTED

NOTES:

1. Slave Control Method (CTRL) must be configured for 0.

2. Slave SCN Address (SCNA) must be different than Master.

3. Slave SCN Bus Number (SCNB) must be the same as Master

4. Slave does not require SLVA, LLBL, LLBD, or LLDY to be configured.

ENTER

ESCAPE

ESCAPE

MSSL

RSET SLAVE COMPLETE

40

Table 23 — Operating Modes

MODE

NO.

01

02

03

05

06

07

08

09

10

13

14

15

16

17

18

19

20

21

22

23

24

25

26

ITEM EXPANSION DESCRIPTION

FSM CONTROLLING CHILLER Flotronic™ System Manager (FSM) is controlling the chiller.

WSM CONTROLLING CHILLER Water System Manager (WSM) is controlling the chiller.

MASTER/SLAVE CONTROL Dual Chiller control is enabled.

RAMP LOAD LIMITED Ramp load (p ull-down) limiting in effect. In this mode, the rate at which leaving fluid temperature

TIMED OVERRIDE IN EFFECT Timed override is in effect. This is a 1 to 4 hour temporary override of the programmed

LOW COOLER SUCTION TEMPA Circuit A cooler Freeze Protection mode. At least one compressor must be on, and the Sat-

LOW COOLER SUCTION TEMPB Circuit B cooler Freeze Protection mode. At least one compressor must be on, and the Sat-

SLOW CHANGE OVERRIDE Slow change override is in effect. The leaving fluid temperature is close to and moving

MINIMUM OFF TIME ACTIVE Chiller is being held off by Minutes Off Time (DELY) [Configuration, OPT2].

DUAL SETPOINT Dual Set Point mode is in effect. Chiller controls to Cooling Set Point 1 (CSP.1) [Set Point,

TEMPERATURE RESET Temperature reset is in effect. In this mode, chiller is using temperature reset to adjust leav-

DEMAND/SOUND LIMITED Demand limit is in effect. This indicates that the capacity of the chiller is being limited by

COOLER FREEZE PROTECTION Cooler fluid temperatures are approaching the Freeze point (see Alarms and Alerts section

LOW TEMPERATURE COOLING Chiller is in Cooling mode and the rate of change of the leaving fluid is negative and

HIGH TEMPERATURE COOLING Chiller is in Cooling mode and the rate of change of the leaving fluid is positive and increasing.

MAKING ICE Chiller is in an unoccupied mode and is using Cooling Set Point 3 (CSP.3) [Set Point, COOL]

STORING ICE Chiller is in an unoccupied mode and is controlling to Cooling Set Point 2 (CSP.2) [Set Point

HIGH SCT CIRCUIT A Chiller is in a Cooling mode and the Saturated Condensing Temperature (SCT) is greater than

HIGH SCT CIRCUIT B Chiller is in a Cooling mode and the Saturated Condensing Temperature (SCT) is greater than

MINIMUM COMP ON TIME Cooling load may be satisfied, however control continues to operate compressor to ensure

PUMP OFF DELAY TIME Cooling load is satisfied, however cooler pump continues to run for the number of minutes set

LOW SOUND MODE Chiller operates at higher condensing temperature and/or reduced

SHORT LOOP OVERRIDE Chiller is monitoring how fast compressor(s) is being cycled to maintain the desired leaving

is dropped is limited to a predetermined value to prevent compressor overloading. See Cooling
Ramp Loading (CRMP) [Configuration, SLCT]. The pull-down limit can be modified, if desired,
to any rate from 0.2° F to 2° F (0.1° to 1° C)/minute.

schedule, forcing unit to Occupied mode. Override can be implemented with unit under
Local (Enable) or SCN (Sterlco Comfort Network) control. Override expires after each use.

urated Suction Temperature is not increasing greater than 1.1° F (0.6° C) in 10 seconds. If
the saturated suction temperature is less than the Brine Freeze Point (BR.FZ) [Set Point,
FRZ] minus 3° F (1.7° C) and less than the leaving fluid temperature minus 14° F (7.8° C)
for 2 minutes, a stage of capacity will be removed from the circuit. Or, If the saturated suc­tion temperature is less than the Brine Freeze Point (BR.FZ) [Set Point, FRZ] minus 14° F
(7.8 º C), for 90 seconds, a stage of capacity will be removed from the circuit. The control
will continue to decrease capacity as long as either condition exists.

urated Suction Temperature is not increasing greater than 1.1° F (0.6° C) in 10 seconds. If
the saturated suction temperature is less than the Brine Freeze Point (BR.FZ) [Set Point,
FRZ] minus 3° F (1.7° C) and less than the leaving fluid temperature minus 14° F (7.8° C)
for 2 minutes, a stage of capacity will be removed from the circuit. Or, If the saturated suc­tion temperature is less than the Brine Freeze Point (BR.FZ) [Set Point, FRZ] minus 14° F
(7.8° C), for 90 seconds, a stage of capacity will be removed from the circuit. The control will
continue to decrease capacity as long as either condition exists.

towards the control point.

COOL] during occupied periods and Cooling Set Point 2 (CSP.2) [Set Point, COOL] during
unoccupied periods.

ing fluid set point upward and is currently controlling to the modified set point. The set point
can be modified based on return fluid, outdoor-air-temperature, space temperature, or 4 to
20 mA signal.

demand limit control option. Because of this limitation, the chiller may not be able to pro­duce the desired leaving fluid temperature. Demand limit can be controlled by switch inputs
or a 4 to 20 mA signal.

for definition). The chiller will be shut down when either fluid temperature falls below the
Freeze point.

decreasing faster than -0.5° F per minute. Error between leaving fluid and control point
exceeds fixed amount. Control will automatically unload the chiller if necessary.

Error between leaving fluid and control point exceeds fixed amount. Control will automatically
load the chiller if necessary to better match the increasing load.

to make ice. The ice done input to the Energy Management Module (EMM) is open.

COOL]. The ice done input to the Energy Management Module (EMM) is closed.

the calculated maximum limit. No additional stages of capacity will be added. Chiller capacity
may be reduced if SCT continues to rise to avoid high-pressure switch trips by reducing con­densing temperature.

the calculated maximum limit. No additional stages of capacity will be added. Chiller capacity
may be reduced if SCT continues to rise to avoid high-pressure switch trips by reducing con­densing temperature.

proper oil return. May be an indication of oversized application, low fluid flow rate or low loop
volume.

by the configuration variable Cooler Pump Shutdown Delay (PM.DY) [Configuration, OPT1].

capacity to minimize overall unit noise during evening/night hours (user-configurable).

fluid temperature. Control is limiting the rate of compressor cycling when this mode is active
to ensure proper oil return and also to prevent premature compressor failure. Low loop vol­ume, low cooler flow and/or low chiller load are the primary causes for this mode.

41

Table 24 — Example of Reading and Clearing Alarms

SUB-MODE

CRNT

CRNT

KEYPAD

ENTRY

ENTER

ESCAPE

ITEM ITEM EXPANSION COMMENT

AXXX or TXXX CURRENTLY ACTIVE ALARMS

NO Use to clear active alarms/alerts

ENTER

NO NO Flashes

RCRN

YES Select YES

ENTER

NO Alarms/aler ts clear, YES changes to NO

Table 25A — 4-20 mA Reset

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

RSET

ENTER

CRST 1

CRT1 4.0

CRT2 20.0

DGRC

5.0 F

(2.8 C)

NOTE: The example above shows how to configure the chiller for 4-20 mA reset. No reset will occur
at 4.0 mA input, and a 5.0 F reset will occur at 20.0 mA. An EMM is required.

ITEM

EXPANSION

COOLING RESET

TYPE

NO COOL RESET

TEMP

FULL COOL

RESET TEMP

DEGREES COOL

RESET

ACTIVE ALARMS (AXXX) OR
ALERTS (TXXX) DISPLAYED.

COMMENT

0 = no reset
1 = 4 to 20 mA input
2 = Outdoor air temp
3 = Return Fluid
4 = Space Temperature

Default: 125 F (51.7 C)
Range: 0° to 125 F

Default: 0° F (–17.8 C)
Range: 0° to 125 F

Default: 0° F (0° C) Reset at 20 mA
Range: –30 to 30 F (–16.7 to 16.7 C)

MODE

(RED LED)

CONFIGURATION

Table 25B — Menu Configuration of 4 to 20 mA Cooling Set Point Control

KEYPAD

ENTRY

ENTER

SUB-MODE

KEYPAD

ENTRY

ITEM DISPLAY

DISP

UNIT

OPT1

OPT2

RSET

SLCT CLSP 0 COOLING SETPOINT SELECT

ENTER

ENTER

ENTER

0 Scrolling Stops

0 Flashing ‘0’

4 Select ‘4’

ENTER

4 Change Accepted

ITEM

EXPANSION

COMMENT

42

Table 26A — Configuring Outdoor Air and Space Temperature Reset

MODE

(RED LED)

CONFIGURATION

*4 items skipped in this example.

MODE

(RED LED)

CONFIGURATION

*4 items skipped in this example.

KEYPAD

ENTRY

ENTER

KEYPAD

ENTRY

ENTER ENTER

SUB-

MODE

DISP

UNIT

OPT1

OPT2

RSET CRST 2 4

KEYPAD

ENTRY

ENTER

ITEM

RM.NO* 85 °F 72 °F

RM.F 55 °F 68 °F

RM.DG 15 °F6 °F

DISPLAY

Outdoor

Air

Space

EXPANSION

COOLING RESET

REMOTE - NO

RESET TEMP

REMOTE - FULL

RESET TEMP

REMOTE - DEGREES

Table 26B — Configuring Return Temperature Reset

SUB-MODE

DISP TEST ON/OFF TEST DISPLAY LEDs

UNIT TYPE X UNIT TYPE

OPT1 FLUD X COOLER FLUID

OPT2 CTRL X CONTROL METHOD

RSET CRST X COOLING RESET TYPE

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ENTER

ITEM DISPLAY

RT.NO* XXX.X

RT.F XXX.X

RT.DG XX.X ∆F

∆

F

RETURN FLUID - FULL

∆

F

RETURN - DEGREES

ITEM

EXPANSION

RETURN FLUID - NO

RESET TEMP

RESET TEMP

RESET

ITEM

TYPE

RESET

COMMENT

2 = Outdoor-Air Temperature
4 = Space Temperature
(Connect to TB5-5,6)

Default: 125.0 F (51.7 C)
Range: 0° to125 F

Default: 0.0° F (-17.7 C)
Range: 0° to 125 F

Default: 0° F (0° C)
Range: –30 to 30 F
(–34.4 to -1.1 °C)

COMMENT

0 = No Reset
1 = 4 to 20 mA Input (EMM required)

(Connect to EMM TB6-2,3)
2 = Outdoor-Air Temperature
3 = Return Fluid
4 = Space Temperature
(Connect to TB5-5,6)

Default: 10.0 ∆F (5.6 ∆C)
Range: 0° to125 F COOLER ∆T

∆

Default: 0
Range: 0° to 125 F COOLER

Default: 0
Range: –30 to 30°F (–16.7 to 16.7 C)

F (–17.8 ∆C)

∆

F (0 ∆C)

∆

T

Temperature Reset —

The control system is capable of
handling leaving-fluid temperature reset based on return cooler
fluid temperature. Because the change in temperat ure through
the cooler is a measure of the building load, the return tempera­ture reset is in effect an average building lo ad reset method.
The control system is also capable of temperature res et based
on outdoor-air temperature (OAT), space temperature (SPT), or
from an externally powered 4 to 20 mA signal. Accessory sen­sors must be used for SPT reset (33ZCT55SPT). The Energy
Management Module (EMM) must be used for temperature
reset using a 4 to 20 mA signal. See Tables 25A and 25B.

IMPORTANT: Care should be taken when interfacing with
other control systems due to possible power supply differ­ences: full wave bridge versus half wave rectification. Con­nection of control devices with different power supplies
may result in permanent damage. ComfortLink™ controls
incorporate power supplies with half wave rectification. A
signal isolation device should be utilized if the signal gen­erator incorporates a full wave bridge rectifier.

To use Outdoor Air or Space Temperature reset, four vari­ables must be configured. In the Configuration mode under the
sub-mode RSET, items CRST, RM.NO, RM.F and RT.DG
must be properly set. See Table 26A — Configuring Outdoor
Air and Space Temperature Reset. The outdoor air reset exam­ple provides 0° F (0° C) chilled water set point reset at 85.0 F
(29.4 C) outdoor-air temperature and 15.0 F (8.3 C) reset at

55.0 F (12.8 C) outdoor-air temperature. The space tempera­ture reset example provides 0° F (0° C) chilled water set point
reset at 72.0 F (22.2 C) space temperature and 6.0 F (3.3 C)
reset at 68.0 F (20.0 C) space temperature. The variable CRST
should be configured for the type of reset desired. The variable
RM.NO should be set to the temperature tha t no reset should
occur. The variable RM.F should be set to the temperature that
maximum reset is to occur. The variable RM.DG should be set
to the maximum amount of reset desired.

To use Return reset, four variables must be configured. In
the Configuration mode under the sub-mode RSET, items
CRST, RT.NO, RT.F and RT.DG must be properly set. See
T able 26B — Configuring Return Temperature Reset. This ex­ample provides 5.0 F (2.8 C) chilled water set point reset at

43

2.0 F (1.1 C) cooler ∆T and 0° F (0° C) reset at 10.0 F (5.6 C)

LEGEND

LW T —

Leaving Water (Fluid) Temperature

Fig. 19 — Outdoor-Air Temperature Reset

LEGEND

LW T —

Leaving Water (Fluid) Temperature

Fig. 20 — Space Temperature Reset

cooler ∆T. The variable RT.NO should be set to the cooler
temperature difference (∆T) where no chilled water tempera­ture reset should occur. The variable RT.F should be set to the
cooler temperature difference where the maximum chilled wa­ter temperature reset should occur. The variable RM.DG
should be set to the maximum amount of reset desired.

To verify that reset is functioning correctly proceed to Run
Status mode, sub-mode VIEW , and subtract the active set point
(SETP) from the control point (CTPT) to determine the degrees
reset.

Under normal operation, the chiller will maintain a constant
leaving fluid temperature approximately equal to the chilled
fluid set point. As the cooler load varies, the entering cooler
fluid will change in proportion to the load as shown in Fig. 18.
Usually the chiller size and leaving-fluid temperature set point
are selected based on a full-load condition. At part load, the flu­id temperature set point may be colder than required. If the
leaving fluid temperature was allowed to increase at part load,
the efficiency of the machine would increase.

Return temperature reset allows for the leaving temperature
set point to be reset upward as a function of the return fluid
temperature or, in effect, the building load.

Figures 19 and 20 are examples of outdoor air and space
temperature resets.

LEGEND

EWT —
LW T —

Entering Water (Fluid) Temperature
Leaving Water (Fluid) Temperature

Fig. 18 — Standard Chilled Fluid

Temperature Control — No Reset

Demand Limit —

the unit capacity to be limited during periods of peak energy us­age. There are 3 types of demand limiting that can be config­ured. The first type is through 2-stage switch control, which will

Demand Limit is a feature that allows

reduce the maximum capacity to 2 user-configurable percentag­es. The second type is by 4 to 20 mA signal input which will re­duce the maximum capacity linearly between 100% at a 4 mA
input signal (no reduction) down to the u ser-configurable lev el
at a 20 mA input signal. The third type uses the CNN Loadshed
module and has the ability to limit the current operating capaci­ty to maximum and further reduce the cap acity if required .

NOTE: The 2-stage switch control and 4- to 20-mA input sig­nal types of demand limiting require the Energy Management
Module (EMM).

T o use D emand Limit, select the type of demand limiting to
use. Then configure the Demand Limit set points based on the
type selected.

DEMAND LIMIT (2-Stage Switch Controlled) — To con­figure Demand Limit for 2-stage switch control set the Demand
Limit Select (DMDC) [Configuration, RSET] to 1. Then

configure the 2 Demand Limit Switch points (DLS1 and DLS2)
[Configuration, RSET] to the desired capacity limit. See
T able 27. Capacity steps are controlled by 2 relay switch inputs
field wired to TB6 as shown in Fig. 4-6.

For Demand Limit by 2-stage switch control, closing the
first stage demand limit contact will put the unit on the first de­mand limit level. The unit will not exceed the percentage of ca­pacity entered as Demand Limit Switch 1 set point. Closing
contacts on the second demand limit switch prevents the unit
from exceeding the capacity entered as Dem and Limit Swit ch
2 set point. The demand limit stage that is set to the lowest de­mand takes priority if both demand limit inputs are closed. If
the demand limit percentage does not match unit staging, th e
unit will li mit cap aci ty to the clo ses t ca pa city sta ge.

To disable demand limit configure the DMDC to 0. See
Table 27.

EXTERNALLY POWERED DEMAND LIMIT (4 to
20 mA Controlled) — To configure Demand Limit for 4 to 20
mA control set the Demand Limit Select (DMDC) [Configura­tion, RSET] to 2. Then configure the Demand Limit at 20 mA
(DM20) [Configuration, RSET] to the maximum loadshed val­ue desired. Connect the output from an externally powered 4 to
20 mA signal to terminal block TB6, terminals 1 and 5. Refer
to the unit wiring diagram for these connections to the optional/
accessory Energy Management Module and terminal block.
The control will reduce allowable capacity t o this level for the
20 mA signal. See Table 27 and Fig. 21A.

44

100

80

60

100% CAPACITY AT 4 mA

40

20

MAX. ALLOWABLE LOAD (%)

0

0

2

4

75% CAPACITY AT 12 mA

6

DEMAND LIMIT SIGNAL – 4 - 20 mA INPUT

8

Fig. 21A — 4- to 20-mA Demand Limiting

Care should be taken when interfacing with other manufac­turer’s control systems, due to possible power supply
differences, full wave bridge versus half wave rectification.
The two different power supplies cannot be mixed.
ComfortLink™ controls use half wave rectification. A sig­nal isolation device should be utilized if a full wave bridge
signal generating device is used.

DEMAND LIMIT (SCN Loadshed Controlled) — To con­figure Demand Limit for SCN Loadshed control set the De­mand Limit Select (DMDC) [Configuration, RSET] to 3. Then
configure the Loadshed Group Number (SHNM), Loadshed
Demand Delta (SHDL), and Maximum Loadshed Time
(SHTM) [Configuration, RSET]. See Table 27.

The Loadshed Group number is established by the SCN
system designer. The ComfortLink control will respond to a
Redline command from the Loadshed control. When the

50% CAPACITY AT 20 mA

10

12

14

16 18

20

Redline command is received, the current stage of capacity is
set to the maximum stages available. Should the loadshed con­trol send a Loadshed command, the ComfortLink control will
reduce the current stages by the value entered for Loadshed
Demand delta. The Maximum Loadshed Time is the maximum
length of time that a loadshed condition is allowed to exist. The
control will disable the Redline/Loadshed command if no Can­cel command has been received within the configured maxi­mum loadshed time limit.

Cooling Set Point (4 to 20 mA) —

A field supplied
and generated, externally powered 4 to 20 mA signal can be
used to provide the leaving fluid temperature set point. Connect
the signal to TB6-3,5 (+,–). See Table 27 for instructions to
enable the function. Figure 21B shows how the 4 to 20 mA sig­nal is linearly calculated on an overall 10 F to 80 F range for
fluid types (FLUD) 1 or 2 [Configuration, OP T1]. The set point
will be limited by the fluid (FLUD) type. Be sure that the
chilled water loop is protected at the lowest temperature.

SET POINT, F (C)

EMM —

100

(38)

90

(32)

80

(27)

70

(21)

60

(15)

50

(10)

40

(4.4)

30

(-1)

20

(-7)

10

(-12)

0

(-17)

Energy Management Module

4 6.3 8.6 10.9 13.1 15.4 17.7 20

(FLUD = 2) MINIMUM
SET POINT 14 F (-10 C)

(FLUD = 1) MINIMUM
SET POINT 38 F (3.3 C)

4 TO 20 mA SIGNAL TO EMM

MAXIMUM
SET POINT
70 F (21.1 C)

Fig. 21B — Cooling Set Point (4 to 20 mA)

45

Table 27 — Configuring Demand Limit

MODE

CONFIGURATION

*Seven items skipped in this example.

KEYPAD

ENTRY

ENTER ENTER

SUB-MODE

KEYPAD

ENTRY

DISP TEST ON/OFF Test Display LEDs

UNIT TYPE X Unit Type

OPT1 FLUD X Cooler Fluid

OPT2 CTRL X Control Method

RSET CRST X Cooling Reset Type

ENTER

ENTER

ENTER

ENTER

ITEM DISPLAY ITEM EXPANSION COMMENT

DMDC* X Demand Limit Select

DM20 XXX % Demand Limit at 20 mA

SHNM XXX

SHDL XXX%

SHTM XXX MIN

DLS1 XXX %

DLS2 XXX %

Loadshed Group

Number

Loadshed Demand

Delta

Maximum Loadshed

Time

Demand Limit

Switch 1

Demand Limit

Switch 2

Default: 0
0 = None
1 = Switch
2 = 4 to 20 mA Input
3 = SCN Loadshed

Default: 100%
Range: 0 to 100

Default: 0
Range: 0 to 99

Default: 0%
Range: 0 to 60%

Default: 60 min.
Range: 0 to 120 min.

Default: 80%
Range: 0 to 100%

Default: 50%
Range: 0 to 100%

TROUBLESHOOTING

Complete Unit Stoppage and Restart —

ble causes for unit stoppage and reset methods are shown be­low. (See Table 28 also.) Refer to Fig. 22-26 for Component
Arrangement and Control Wiring Diagrams.

GENERAL POWER FAILURE — Af ter power is restored,
restart is automatic through normal MBB start-up.

UNIT ENABLE-OFF-REMOTE CONTACT SWITCH IS
OFF — When the switch is OFF, the unit will stop immediate­ly. Place the switch in the ENA BLE position fo r local swit ch
control or in the REMOTE CONTACT position for control
through remote contact closure.

CHILLED FLUID PROOF-OF-FLOW SWITCH OPEN —
After the problem causing the loss of flow has been corrected,
reset is manual by resetting the al arm with the Scrolling Mar ­quee as shown in Table 24.

OPEN HIGH-PRESSURE SWITCH(ES) — Determine and
correct the cause of the failure. The switch automatically resets,
but the unit must be reset manually by resetting the alarm with
the Scrolling Marquee as shown in Table 24.

OPEN COMPRESSOR INTERNAL THERMAL PRO­TECTION — This switch provides compressor over tempera­ture protection. Determine and correct the cause of the prob­lem. The switc h re se ts auto m a t ic al ly, but the unit must be reset
manually resetting the alarm with the Scrolling Marquee as
shown in T able 24.

Possi-

OPEN 24-V CONTROL CIRCUIT BREAKER(S) — De­termine the cause of the failure and correct. Reset circuit break­er(s). Restart is automatic after MBB start-up cycle is com­plete.

COOLING LOAD SATISFIED — Unit shuts down when
cooling load has been satisfied. Unit restarts when required t o
satisfy leaving fluid temperature set point.

THERMISTOR FAILURE — If a th er m i stor f a i l s in eit h e r a n
open or shorted condition, the unit will be shut down. Replace
T1, T2, or T9 as required. Unit restarts automatically, but must
be reset manually by resetting the alarm with the Scrolling
Marquee as shown in Table 24.

If unit stoppage occurs more than once as a result of any of
the safety devices listed, determine and correct cause
before attempting another restart.

LOW SATURATED SUCTION — Several conditions can
lead to low saturated suction alarms and the c hiller controls
have several override modes built in which will attempt to keep
the chiller from shutting down. Low fluid flow, low refrigerant
charge and plugged filter driers are the main causes for this
condition. To avoid permanent damage and potential freezing
of the system, do NOT repeatedly reset these alert and/or alarm
conditions without identifying and correcting the cause(s).

46

SYMPTOMS CAUSE REMEDY

Cooler Circulating Pump Does
Not Run

Compressor Cycles
Off on Loss of Charge

Compressor Cycles Off on Out
of Range Condition

Compressor Shuts Down on
High-Pressure Control

Unit Operates Too Long
or Continuously

Unusual or Loud System
Noises

Compressor Loses Oil

Hot Liquid Line
Frosted Liquid Line

Frosted Suction Line

Freeze-Up

Table 28 — Troubleshooting

Power line open Reset circuit breaker.
Control fuse or circuit breaker open Check control circuit for ground or short. Reset

Compressor over temperature sensor open (06D) Find cause of high temperature and reset controls.
Tripped power breaker Check the controls. Find the cause of trip and reset

Cooler circulating pump not running Power off — restar t.

Loose terminal connection Check connections.
Improperly wired controls Check wiring and rewire if necessary.
Low line voltage Check line voltage — determine location of

Compressor motor defective Check motor winding for open or short.

Seized compressor Replace compressor.
Loss of charge control erratic in action Repair leak and recharge.

Low refrigerant charge Add refrigerant.
Low suction temperature Raise cooler leaving fluid temperature set point.
Thermistor failure Replace thermistor.
System load was reduced faster than controller

could remove stages

Temperature controller deadband setting is too low Raise deadband setting.
High-pressure control acting erratically Replace control.
Compressor discharge valve partially closed Open valve or replace (if defective).
Noncondensables in system Purge system.
Condenser scaled/dirty Clean condenser.
Condenser water pump or fans not operating Start pump — repair or replace if defective.
System overcharged with refrigerant Reduce charge.
Low refrigerant charge Add refrigerant.
Control contacts fused Replace control.
Air in system Purge system.
Partially plugged or plugged expansion valve or filter

drier
Defective insulation Replace or repair as needed.
Service load Keep doors and windows closed.
Inefficient compressor Check valves, and replace if necessary.
Piping vibration Support piping as required.

Expansion valve hissing Add refrigerant.

Compressor noisy Replace compressor (worn bearings).

Leak in system Repair leak.
Mechanical damage (Failed seals or broken scrolls) Replace compressor.
Oil trapped in line Check piping for oil traps.
Shortage of refrigerant due to leak Repair leak and recharge.
Shutoff valve partially closed or restricted Open valve or remove restriction.
Restricted filter drier Replace filter drier.
Expansion valve admitting excess refrigerant (note:

this is a normal condition for brine applications)
Improper charging Make sure a full quantity of fluid is flowing through

System not drained for winter shutdown

Loose Thermistor Verify thermistors are fully inserted in wells.

breaker and replace fuse.

breaker.

Pump binding — free pump.
Incorrect wiring —rewire.
Pump motor burned out — replace.

voltage drop and remedy deficiency.

Replace compressor if necessary.

Replace control.

Unit will restart after fluid temperature rises back into
the control band. Avoid rapidly removing system
load.

Clean or replace as needed.

Check for loose pipe connections

Check for plugged liquid line filter drier.

Check for loose compressor holddown bolts.

Adjust expansion valve. Replace valve if defective.

the cooler while charging, and suction pressure in
cooler is equal to or greater than pressure corre­sponding to 32 F (0° C) (58 psig [400 kPa] for
Refrigerant 22).

Recommended that system be filled with an appro­priate glycol mixture to prevent freezing of pumps
and fluid tubing.

47

C — Contactor, Compressor
CB — Circuit Breaker
CHC — Cooler/Pump Heater Contactor
CWP — Chilled Water Pump
EMM — Energy Management
FC — Fan Contactor
FIOP — Factory-Installed Option
FU — Fuse
GND — Ground
MBB — Main Base Board
MM — Motormaster®
MMPT — Motormaster Pressure Transducer
MS — Manual Starter
NEC — National Electrical Code
SW — Switch
TB — Terminal Block
TRAN — Transformer

LEGEND

Factory Wiring

Field Wiring

Accessory or Option Wiring

Fig. 22 — Component Arrangement — 30RA010-030

48

LEGEND

C — Contactor, Compressor
CB — Circuit Breaker
CHC — Cooler/Pump Heater Contactor
CWP — Chilled Water Pump
EMM — Energy Management
FC — Fan Contactor
FIOP — Factory-Installed Option
FU — Fuse
GND — Ground
MBB — Main Base Board
MM — Motormaster®
MMPT — Motormaster Pressure Transducer
MS — Manual Starter
NEC — National Electrical Code
SW — Switch
TB — Terminal Block
TRAN — Transformer

Factory Wiring

Field Wiring

Accessory or Option Wiring

Fig. 23 — Component Arrangement — 30RA032-040

49

LEGEND

C — Contactor, Compressor
CB — Circuit Breaker
CHC — Cooler/Pump Heater Contactor
CWP — Chilled Water Pump
EMM — Energy Management
FC — Fan Contactor
FIOP — Factory-Installed Option
FU — Fuse
GND — Ground
MBB — Main Base Board
MM — Motormaster®
MMPT — Motormaster Pressure Transducer
MS — Manual Starter
NEC — National Electrical Code
SW — Switch
TB — Terminal Block
TRAN — Transformer

Factory Wiring

Field Wiring

Accessory or Option Wiring

Fig. 24 — Component Arrangement — 30RA042-055

50

LEGEND

A — Alarm

CWPI — Chilled Water Pump Interlock

CWP — Chilled Water Pump

EMM — Energy Management

FIOP — Factory-Installed Option

Field Power Wiring

Field Control Wiring

Factory-Installed Wiring

NEC — National Electrical Code

SPT — Space Temperature

TB — Te r mi na l Bl oc k

Fig. 25 — Control and Field Power Wiring Diagram — 30RA010-030

Link™ controls use half wave rectification. A signal isolation device

or additions must be in compliance with all applicable codes.

units. Maximum incoming wire size for the terminal block is #2/0 AWG. Max-

imum incoming wire size for 60 and 100 amp non-fused disconnect is

#1 AWG. Maximum incoming wire size for 250 amp non-fused disconnect is

350 kcmil.

off. The contacts must be rated for dry circuit application capable of handling

a 24 vac load up to 50 mA.

flow switch (CWFS). To add chilled water pump interlock contacts, remove

the orange harness wire from TB5-1 and wire contacts in series as shown.

The contacts must be rated for dry circuit application capable of handling a

24 vac load up to 50 mA.

starter. Terminals 13 and 15 of TB5 are for control of chilled water pump 2

(CWP2) starter. The maximum load allowed for the chilled water pump relay

is 5 va sealed, 10 va inrush at 24 v. Field power supply is not required.

allowed for the alarm relay is 5 va sealed, 10 va inrush at 24 v. Field power

supply is not required.

board options. The contacts for demand limit and ice done options must be

rated for dry circuit application capable of handling a 24 vac load up to

50 mA.

systems due to possible power supply differences: full wave bridge versus

half wave rectification. The two different power supplies cannot be mixed.

Comfort

NOTES:

1. Factory wiring is in accordance with UL 1995 standards. Field modifications

2. Wiring for main field supply must be rated 75 C minimum. Use copper for all

3. Terminals 9 and 10 of TB5 are for field external connections for remote on-

4. Terminals 1 and 2 of TB5 are connected to the factory-installed chilled water

5. Terminals 11 and 13 of TB5 are for control of chilled water pump 1 (CWP1)

6. Terminals 12 and 13 of TB5 are for an alarm relay. The maximum load

7. Make appropriate connections to TB6 as shown for energy management

should be utilized if a full wave bridge signal generating device is used.

8. Care should be taken when interfacing with other manufacturer’s control

51

LEGEND

A — Alarm

CWPI — Chilled Water Pump Interlock

CWP — Chilled Water Pump

EMM — Energy Management

FIOP — Factory-Installed Option

Field Power Wiring

Field Control Wiring

Factory-Installed Wiring

NEC — National Electrical Code

SPT — Space Temperature

TB — Terminal Block

NOTES:

Fig. 26 — Control and Field Power Wiring Diagram — 30RA032-055

Link™ controls use half wave rectification. A signal isolation device

or additions must be in compliance with all applicable codes.

units. Maximum incoming wire size for the terminal block is 350 kcmil. Maxi-

mum incoming wire size for 100 amp non-fused disconnect is #1 AWG. Maxi-

mum incoming wire size for 250 amp non-fused disconnect is 350 kcmil.

The contacts must be rated for dry circuit application capable of handling a

24 vac load up to 50 mA.

flow switch (CWFS). To add chilled water pump interlock contacts, remove the

orange harness wire from TB5-1 and wire contacts in series as shown. The

contacts must be rated for dry circuit application capable of handling a 24 vac

load up to 50 mA.

starter. Terminals 13 and 15 of TB5 are for control of chilled water pump 2

(CWP2) starter. The maximum load allowed for the chilled water pump relay

is 5 va sealed, 10 va inrush at 24 v. Field power supply is not required.

allowed for the alarm relay is 75 va sealed, 360 va inrush at 115 v. Field

power supply is not required.

board options. The contacts for demand limit and ice done options must be

rated for dry circuit application capable of handling a 24 vac load up to 50 mA.

systems due to possible power supply differences: full wave bridge versus

half wave rectification. The two different power supplies cannot be mixed.

Comfort

1. Factory wiring is in accordance with UL 1995 standards. Field modifications

2. Wiring for main field supply must be rated 75 C minimum. Use copper for all

3. Terminals 9 and 10 of TB5 are for field external connections for remote on-off.

4. Terminals 1 and 2 of TB5 are connected to the factory-installed chilled water

5. Terminals 11 and 13 of TB5 are for control of chilled water pump 1 (CWP1)

6. Terminals 12 and 13 of TB5 are for an alarm relay. The maximum load

7. Make appropriate connections to TB6 as shown for energy management

should be utilized if a full wave bridge signal generating device is used.

8. Care should be taken when interfacing with other manufacturer’s control

52

Alarms and Alerts —

These are warnings of abnormal
or fault conditions, and may cause either one circuit or the
whole unit to shut down. They are assigned code numbe rs as
described in Table 29.

Automatic alarms will reset without operator intervention if
the condition corrects itself. The following method must be
used to reset manual alarms:

Before resetting any alarm, first determine the cause of the
alarm and correct it. Enter the Alarms mode i ndicated by the
LED on the side of the Scrolling Marquee Display. Press

ENTER

and until the sub-menu item RCRN “RESET

Table 29 — Alarm and Alert Codes

ALL CURRENT ALARMS” is displayed. Press .

ENTER
The control will prompt the user for a password, by displaying
PASS and WORD. Press to display the default pass­wo rd, 1111. Pre ss for each char acter. If the password

ENTER

ENTER
has been changed, use the arrow keys to change each individu­al character. Toggle the display to “YES” and press .

ENTER

The alarms will be reset.

ALARM/

ALERT

CODE

ALARM

OR

ALERT

T051 Alert Circuit A, Compressor 1

T052 Alert Circuit A, Compressor 2

T055 Alert Circuit B, Compressor 1

T056 Alert Circuit B, Compressor 2

A060 Alarm Cooler Leaving Fluid

A061 Alarm Cooler Entering Fluid

T068 None Circuit A Return Gas Thermistor Failure If return gas sensors are

T069 None Circuit B Return Gas Thermistor Failure If return gas sensors are

T073 Alert Outside Air Thermistor

T074 Alert Space Temperature

T077 Aler t Circuit A Saturated

T078 Aler t Circuit B Saturated

T079 Alert Lead/Lag LWT

T090 Aler t Circuit A Discharge

T091 Aler t Circuit B Discharge

T092 Aler t Circuit A Suction

Failure

Failure

Failure

Failure

Thermistor Failure (T1)

Thermistor Failure (T2)

Failure (T9)

Thermistor Failure (T10)

Suction Temperature
exceeds Cooler Leaving
Fluid Temperature

Suction Temperature
exceeds Cooler Leaving
Fluid Temperature

Thermistor Failure

Pressure Transducer Failure

Pressure Transducer Failure

Pressure Transducer Failure

DESCRIPTION

WHY WAS THIS

ALARM

GENERATED?

Compressor feedback signal
does not match relay state

Compressor feedback signal
does not match relay state

Compressor feedback signal
does not match relay state

Compressor feedback signal
does not match relay state

Thermistor outside range of
–40 to 245 F (–40 to 118 C)

Thermistor outside range of
–40 to 245 F (–40 to 118 C)

enabled (RG.EN) and
thermistor is outside range of
–40 to 245 F (–40 to 118 C)

enabled (RG.EN) and
thermistor is outside range of
–40 to 245 F –40 to 118 C)

Thermistor outside range of
–40 to 245 F (–40 to 118 C)

Thermistor outside range of
–40 to 245 F (–40 to 118 C)

Faulty expansion valve,
suction pressure transducer
or leaving fluid thermistor
(T1).

Faulty expansion valve,
suction pressure transducer
or leaving fluid thermistor
(T1).

Thermistor outside range of
–40 to 245 F (–40 to 118 C)

Voltage ratio more than

99.9% or less than .5%.

Voltage ratio more than

99.9% or less than .5%.

Voltage ratio more than

99.9% or less than .5%.

ACTION TAKEN

BY CONTROL

Compressor A1 shut
down.

Compressor A2 shut
down.

Compressor B1 shut
down.

Compressor B2 shut
down.

Chiller shutdown
immediately

Chiller shutdown
immediately

None Automatic Thermistor failure, damaged

None Automatic Thermistor failure, damaged

Temperature reset
disabled. Chiller runs
under normal control/set
points. When capacity
reaches 0, cooler/pump
heaters are energized.

Temperature reset
disabled. Chiller runs
under normal control/set
points.

Circuit A shutdown after
pumpdown complete.

Circuit B shutdown after
pumpdown complete

Chiller runs as a stand
alone machine

Circuit A shut down Automatic Transducer failure, poor

Circuit B shut down Automatic Transducer failure, poor

Circuit A shut down Automatic Transducer failure, poor

RESET

METHOD

Manual High-pressure switch open,

Manual High-pressure switch open,

Manual High-pressure switch open,

Manual High-pressure switch open,

Automatic Thermistor failure, damaged

Automatic Thermistor failure, damaged

Automatic Thermistor failure, damaged

Automatic Thermistor failure, damaged

Automatic Faulty expansion valve or

Automatic Faulty expansion valve or

Automatic Dual LWT thermistor failure,

PROBABLE

CAUSE

faulty auxiliary contacts, loss
of condenser air, liquid
valve closed, filter drier
plugged, non-condensables,
operation beyond capability.

faulty auxiliary contacts, loss
of condenser air, liquid
valve closed, filter drier
plugged, non-condensables,
operation beyond capability.

faulty auxiliary contacts, loss
of condenser air, liquid
valve closed, filter drier
plugged, non-condensables,
operation beyond capability.

faulty auxiliary contacts, loss
of condenser air, liquid
valve closed, filter drier
plugged, non-condensables,
operation beyond capability.

cable/wire or wiring error.

cable/wire or wiring error.

cable/wire or wiring error.

cable/wire or wiring error.

cable/wire or wiring error.

cable/wire or wiring error.

suction pressure transducer
(T5) or leaving fluid
thermistor (T1).

suction pressure transducer
(T6) or leaving fluid
thermistor (T1).

damaged cable/wire or
wiring error.

connection to MBB, or wiring
damage/error.

connection to MBB, or wiring
damage/error.

connection to MBB, or wiring
damage/error.

53

Table 29 — Alarm and Alert Codes (cont)

ALARM/

ALERT

CODE

T093 Alert Circuit B Suction

T110 Aler t Circuit A Loss of Charge If the compressors are off

T111 Aler t Circuit B Loss of Charge If the compressors are off

T112 Alert Circuit A High Saturated

T113 Alert Circuit B High Saturated

T114 Alert Circuit A Low Suction

T115 Alert Circuit B Low Suction

T116 Alert Circuit A Low Cooler

T117 Alert Circuit B Low Cooler

T126 Alert Circuit A High

T127 Alert Circuit B High

T133 Alert Circuit A Low Suction

T134 Alert Circuit B Low Suction

ALARM

OR

ALERT

DESCRIPTION

Pressure Transducer
Failure

Suction Temperature

Suction Temperature

Superheat

Superheat

Suction Temperature

Suction Temperature

Discharge Pressure

Discharge Pressure

Pressure

Pressure

WHY WAS THIS

ALARM

GENERATED?

Voltage ratio more than

99.9% or less than .5%.

and discharge pressure
reading is < 10 psig for
30 sec.

and discharge pressure
reading is < 10 psig for
30 sec.

Circuit saturated suction
temperature pressure
transducer > 60 F (15.6 C)
for 5 minutes

Circuit saturated suction
temperature pressure
transducer > 60 F (15.6 C)
for 5 minutes

Return gas sensor enabled
and suction superheat is
more than 10° F (5.6 C)
below the suction superheat
set point for 5 minutes.

Return gas sensor enabled
and suction superheat is
more than 10° F (5.6 C)
below the suction superheat
set point for 5 minutes.

Mode 7 caused the com­pressor to unload 6 consecu­tive times with less than a
30-minute interval between
each circuit shutdown.

Mode 8 caused the com­pressor to unload 6 consecu­tive times with less than a
30-minute interval between
each circuit shutdown.

SCT >Maximum condensing
temperature from operating
envelope

SCT >Maximum condensing
temperature from operating
envelope

Suction pressure below
15 psig for 8 seconds or
below 8 psig

Suction pressure below
15 psig for 8 seconds or
below 8 psig

ACTION TAKEN

BY CONTROL

Circuit B shut down Automatic Transducer failure, poor

Circuit not allowed to
start.

Circuit not allowed to
start.

Circuit shut down Manual Faulty Expansion valve,

Circuit shut down Manual Faulty Expansion valve,

Circuit A shut down after
pumpdown complete.

Circuit B shut down after
pumpdown complete.

Circuit shut down Manual Faulty expansion valve, low

Circuit shut down Manual Faulty expansion valve, low

Circuit shut down Automatic, only

Circuit shut down Automatic, only

Circuit shut down Automatic

Circuit shut down Automatic

RESET

METHOD

connection to MBB, or wiring
damage/error.

Manual Refrigerant leak or

Manual Refrigerant leak or

Automatic restart
after first daily
occurrence.
Manual restart
thereafter.

Automatic restart
after first daily
occurrence.
Manual restart
thereafter.

after first 3 daily
occurrences.
Manual reset
thereafter. Read­ing from OAT sen­sor (T9) must drop
5 F (2.8 C) before
restart

after first 3 daily
occurrences. Man­ual reset thereafter.
Reading from OAT
sensor (T9) must
drop 5 F (2.8 C)
before restart

restart after first
daily occurrence.
Manual restart
thereafter.

restart after first
daily occurrence.
Manual restart
thereafter.

transducer failure

transducer failure

faulty suction pressure
transducer or high entering
fluid temperature.

faulty suction pressure
transducer or high entering
fluid temperature.

Faulty expansion valve,
faulty suction pressure
transducer, faulty suction gas
thermistor, circuit
overcharged

Faulty expansion valve,
faulty suction pressure
transducer, faulty suction
gas thermistor, circuit
overcharged

refrigerant charge, plugged
filter drier, faulty suction
pressure transducer, low
cooler fluid flow

refrigerant charge, plugged
filter drier, faulty suction
pressure transducer, low
cooler fluid flow

Faulty transducer/high
pressure switch, low/
restricted condenser
airflow

Faulty transducer/high
pressure switch, low/
restricted condenser
airflow

Faulty or plugged TXV, low
refrigerant charge, TXV out
of adjustment, liquid
line valve partially closed

Faulty or plugged TXV, low
refrigerant charge, TXV out
of adjustment, liquid
line valve partially closed

PROBABLE

CAUSE

54

Table 29 — Alarm and Alert Codes (cont)

ALARM/

ALERT

CODE

A140 Alert Reverse Rotation

A150 Alarm Emergency Stop SCN emergency stop

A151 Alarm Illegal Configuration One or more illegal

A152 Alarm Unit Down Due to

T153 Alert Real Time Clock

A154 Alarm Serial EEPROM

T155 Alert Serial EEPROM

A156 Alarm Critical Serial EEPROM

A157 Alarm A/D Hardware Failure Hardware failure with

A189 Alarm Cooler pump auxiliary

T173 Alert Loss of Communication

T174 Alert 4 to 20 mA Cooling Set

T176 Alert 4 to 20 mA

T177 Alert 4 to 20 mA Demand

T189 Alarm Cooler pump 2 and

T190 Alert Cooler pump 1 Aux

T191 Alert Cooler pump 2 Aux

T192 Alert Cooler pump 1 Failed

T193 Alert Cooler pump 2 Failed

T194 Alert Cooler pump 1 Aux

T195 Alert Cooler pump 2 Aux

ALARM

OR

ALERT

DESCRIPTION

Detected

Failure

Hardware Failure

Hardware Failure

Storage Failure

Storage Failure

contact inputs miswired

with EMM

Point Input Failure

Temperature Reset
Input Failure

Limit Input Failure

Aux Contact Input
miswired

Contacts Failed to Close
at Start-Up

Contacts Failed to Close
at Start-Up

to Provide Flow at
Start-Up

to Provide Flow at
Start-Up

Contacts Opened
During Normal
Operation

Contacts Opened
During Normal
Operation

WHY WAS THIS

ALARM

GENERATED?

Incoming chiller power
leads not phased correctly

command received

configurations exists.

Both circuits are down due
to alarms/aler ts.

Internal clock on MBB fails Occupancy schedule

Hardware failure with MBB Chiller is unable

Configuration/storage
failure with MBB

Configuration/storage
failure with MBB

peripheral device

Pump 1 (2) aux contacts
closed when pump 2 (1)
energized.

MBB loses communication
with EMM

If configured with EMM and
input less than 2 mA or
greater than 22 mA

If configured with EMM
and input less than 2 mA or
greater than 22 mA

If configured with EMM and
input less than 2 mA or
greater than 22 mA

Alarm is generated when
the pump’s aux contacts
close when a pump is
called for

Pump 1 Auxiliary Contacts
did not close within
26 seconds after pump
was started

Pump 2 Auxiliary Contacts
did not close within
26 seconds after pump
was started

Pump 1 did not provide
flow to close flow switch
within 60 seconds

Pump 2 did not provide
flow to close flow switch
within 60 seconds

Pump 1 Auxiliary Contacts
open for 26 seconds after
initially made. All
compressors shut down.
Pump 1 turned off.

Pump 2 Auxiliary Contacts
open for 26 seconds after
initially made. All
compressors shut down.
Pump 2 turned off.

ACTION TAKEN

BY CONTROL

Chiller not allowed to
start.

Chiller shutdown
without going through
pumpdown.

Chiller is not allowed to
start.

Chiller is unable
to run.

will not be used. Chiller
defaults to Local On
mode.

to run.

No Action Manual Potential failure of

Chiller is not allowed
to run.

Chiller is not allowed
to run.

Both pump outputs
are turned off.

4 to 20 mA
temperature reset
disabled. Demand
Limit set to 100%. 4 to
20 mA set point
disabled.

Set point function
disabled. Chiller
controls to CSP1.

Reset function
disabled. Chiller
returns to nor mal set
point control.

Demand limit function
disabled. Chiller
returns to 100%
demand limit
control.

Chiller not allowed to
start

Pump 1 turned off.
Pump 2 will be started
if available.

Pump 2 turned off.
Pump 1 will be started
if available.

Pump 1 turned off.
Pump 2 will be started
if available.

Pump 1 turned off.
Pump 2 will be started
if available.

Pump 2 will be started
if available. Chiller
allowed to run if
Pump 2 successfully
starts.

Pump 1 will be started
if available. Chiller
allowed to run if
Pump 1 successfully
starts.

RESET

METHOD

Manual Reverse any two

Automatic once SCN
command for
EMSTOP returns to
normal

Manual once
configuration errors
are corrected

Automatic once
alarms/aler ts are
cleared that prevent
the chiller from
starting.

Automatic when
correct clock control
restarts.

Manual Main Base Board

Manual Main Base Board

Manual Main Base Board

Manual Wiring error, faulty

Automatic Wiring error, faulty

Automatic Faulty signal

Automatic Faulty signal

Automatic Faulty signal

Manual Wiring error

Manual Wiring error, faulty

Manual Wiring error, faulty

Manual Wiring error, pump

Manual Wiring error, pump

Manual Wiring error, faulty

Manual Wiring error, faulty

PROBABLE

CAUSE

incoming power
leads to correct.
Check for correct fan
rotation first.

SCN Network
command.

Configuration error.
Check unit settings.

Alarm notifies user
that chiller is 100%
down.

Time/Date/Month/
Day/Year not
properly set.

failure.

MBB. Download
current operating
software. Replace
MBB if error occurs
again.

failure.

failure.

pump contactor
auxiliary contacts.

wiring or failed
Energy Manage­ment Module (EMM).

generator, wiring
error, or faulty EMM.

generator, wiring
error, or faulty EMM.

generator, wiring
error, or faulty EMM.

contacts on pump
contactor

contacts on pump
contactor

circuit breaker
tripped, contactor
failure

circuit breaker
tripped, contactor
failure

contacts on pump
contactor

contacts on pump
contactor

55

Table 29 — Alarm and Alert Codes (cont)

ALARM/

ALERT

CODE

T196 Alert Flow Lost While Pump 1

T197 Alert Flow Lost While Pump 2

T198 Alert Cooler pump 1 Aux

T199 Alert Cooler pump 2 Aux

T200 Alert Cooler Flow/Interlock

A201 Alarm Cooler Flow/Interlock

A202 Alarm Cooler Pump Interlock

T203 Alert Loss of Communication

T204 Alert Loss of Communication

T205 Alert Master and slave chiller

T206 Alert High Leaving Chilled

A207 Alarm Cooler Freeze

A208 Alarm EWT or LWT

T300 Alert Cooler Pump 1

ALARM

OR

ALERT

DESCRIPTION

Running

Running

Contacts Closed While
Pump Off

Contacts Closed While
Pump Off

Contacts failed to Close
at start-up

Contacts Opened
During Normal
Operation

Closed When Pump is
Off

with slave chiller

with master chiller

with same address

Water Temperature

Protection

Thermistor failure

Scheduled
Maintenance Due

WHY WAS THIS

ALARM

GENERATED?

Cooler flow switch contacts
open for 3 seconds after
initially made

Cooler flow switch contacts
open for 3 seconds after
initially made

Pump 1 Auxiliary Contacts
closed for 26 seconds
when pump state is off

Pump 2 Auxiliary Contacts
closed for 26 seconds
when pump state is off

Cooler flow switch contacts
failed to close within
1 minute (if cooler pump
control is enabled) or
within 5 minutes (if cooler
pump control is not
enabled) after star t-up

Flow switch opens for at
least 3 seconds after
being initially closed

If configured for cooler
pump control and flow
switch input is closed for
5 minutes while pump
output(s) are off

Master chiller MBB
loses communication
with slave chiller MBB

Slave chiller MBB loses
communication with
master chiller MBB

Master and slave chiller
have the same SCN
address (SCN.A)

LWT read is greater than
LCW Alert Limit, Total
capacity is 100% and LWT
is greater than LWT
reading one minute ago

Cooler EWT or LWT is less
than Brine Freeze (BR.FZ)

Cooler EWT is less than
LWT by 3 ° F (1.7° C) for
1 minute after a circuit is
started

Pump 1 Service
Countdown (P.1.DN)
expired. Complete pump 1
maintenance and enter
'YES' for Pump 1
Maintenance Done
(P.1.MN) item.

ACTION TAKEN

BY CONTROL

All compressors
shut down. Pump 1
turned off. Pump 2 will
be started if available.
Chiller allowed to run if
Pump 2 successfully
starts and flow switch
is closed.

All compressors shut
down. Pump 2 turned
off. Pump 1 will be
star ted if available.
Chiller allowed to run if
Pump 1 successfully
starts and flow switch
is closed.

Chiller not allowed to
start

Chiller not allowed to
start

Chiller not allowed to
start. For models with
dual pumps, the
second pump will be
started if available

All compressors shut
down. For models with
dual pumps, the
second pump will be
started if available

Chiller shut down Automatic when

Dual chiller control
disabled. Chiller runs
as a stand-alone
machine.

Dual chiller control
disabled. Chiller runs
as a stand-alone
machine

Dual chiller routine
disabled. Master/slave
run as stand-alone
chillers.

Alert only. No action
taken.

Chiller shutdown
without going through
pumpdown. Cooler
pump continues to
run a minimum of
5 minutes (if control
enabled).

Chiller shutdown.
Cooler pump shut off
(if control enabled).

None Automatic Routine pump

RESET

METHOD

Manual Wiring error, pump

Manual Wiring error, pump

Automatic when
aux contacts open

Automatic when
aux contacts open

Manual Wiring error, pump

Manual Cooler pump failure,

aux contacts open

Automatic Wiring error, faulty

Automatic Wiring error, faulty

Automatic SCN Address for

Automatic Building load greater

Both EWT and LWT
must be at least 6 F
(3.3 C) above Brine
Freeze point (BR.FZ).
Automatic for first,
Manual reset thereaf­ter.

Manual Faulty cooler pump,

PROBABLE

circuit breaker
tripped, contactor fail­ure

circuit breaker
tripped, contactor
failure

Wiring error, faulty
pump contactor
(welded contacts)

Wiring error, faulty
pump contactor
(welded contacts)

circuit breaker
tripped, contactor
failure, faulty flow
switch or interlock

faulty flow switch or
interlock, pump
circuit breaker
tripped

Wiring error, faulty
pump contactor
(welded contacts)

wiring, failed Slave
chiller MBB module,
power loss at slave
chiller, wrong slave
address.

wiring, failed master
chiller MBB module,
power loss at Master
chiller.

both chillers is the
same. Must be
different. Check
SCN.A under the
OPT2 sub-mode in
Configuration at both
chillers.

than unit capacity,
low water/brine flow
or compressor fault.
Check for other
alarms/alerts.

Faulty thermistor
(T1/T2), low water
flow.

low water flow,
plugged fluid strainer.

maintenance
required

CAUSE

56

Table 29 — Alarm and Alert Codes (cont)

ALARM/

ALERT

CODE

T301 Alert Cooler Pump 2

T302 Alert Strainer Blowdown

T303 Alert Condenser Coil

T950 Alert Loss of Communication

T951 Alert Loss of Communication

T952 Alert Loss of Communication

SCN — Sterlco Comfort Network
EMM — Energy Management Module
EWT — Entering Fluid Temperature
FSM — Flotronic™ System Manager
HSM — Hydronic System Manager
LCW — Leaving Chilled Water
LW T — Leaving Fluid Temperature
MBB — Main Base Board
OAT — Outdoor-Air Temperature
SCT — Saturated Condensing Temperature
TXV — Thermostatic Expansion Valve
WSM — Water System Manager

ALARM

OR

ALERT

LEGEND

DESCRIPTION

Scheduled
Maintenance Due

Scheduled
Maintenance Due

Maintenance Due

with Water System
Manager

with Flotronic™ System
Manager

with Hydronic System
Manager

WHY WAS THIS

ALARM

GENERATED?

Pump 2 Service
Countdown (P.2.DN)
expired. Complete pump 2
maintenance and
enter 'YES' for Pump 1
Maintenance Done
(P.2.MN) item.

Strainer Service
Countdown (S.T.DN)
expired. Complete strainer
blowdown and enter 'YES' for
Strainer Maintenance Done
(S.T.MN) item.

Coil Service Countdown
(C.L.DN) expired.
Complete condenser coil
cleaning and enter 'YES'
for Coil Maintenance Done
(C.L.MN) item.

No communications have
been received by the MBB
within 5 minutes of last
transmission

No communications have
been received by the MBB
within 5 minutes of last
transmission

No communications have
been received by the MBB
within 5 minutes of last
transmission

ACTION TAKEN

BY CONTROL

None Automatic Routine pump

None Automatic Routine strainer

None Automatic Routine condenser

WSM forces removed.
Chiller runs under own
control

FSM forces removed.
Chiller runs under own
control

HSM forces removed.
Chiller runs under own
control

RESET

METHOD

Automatic Failed module, wiring

Automatic Failed module, wiring

Automatic Failed module, wiring

PROBABLE

CAUSE

maintenance
required

maintenance
required

coil maintenance
required

error, failed
transformer, loose
connection plug,
wrong address

error, failed
transformer, loose
connection plug,
wrong address

error, failed
transformer, loose
connection plug,
wrong address

57

SERVICE

Table 30 — Unit Torque Specification

ELECTRIC SHOCK HAZARD.
Turn off all power to unit before servicing. The

ENABLE/OFF/REMOTE CO NTACT switch
on control panel does not shut off control
power; use field disconnect.

Electronic Components

CON T R OL CO MPON E NTS — Unit uses an adva nced e lec­tronic control system that normally does not require service.
For details on controls refer to Operating Data section.

Access to the compressors is through latched panels from
beneath the control box on all models or from opposite the coil
side (sizes 010-030 only). The front door(s) provide access to
the compressor(s) and all components of the refrigeration sys­tem. For size 010-030 units, access to the controls is through
the upper latched outer door above the compressor access door.
Similarly , the upper center latched door on sizes 032-055 gives
access to the controls. Inner panels are secured in place and
should not be removed unless all power to the chiller is off.

Compressor Replacement (Refer to Fig. 27-

30) —

one to four compressors. The size 010-030 units are a single re­frigeration circuit while sizes 032-055 are dual circuit. A com­pressor is most easily removed from the front of the unit, de­pending on where clearance space was allowed during unit
installatio n.

compressor power and ground connections. Remove the cable
from the compressor junction box. Remove the connections
from the internal thermostat and high-pressure switch (all com­pressors except SM110) or high-pressure switch connections
(SM110 only). Knock the same holes out of the new compres­sor junction box and install the cable connec tors from the old
compressor. Remove the blockoff channel from below the con­trol box.

old compressor and installed on the new compressor for those
models with dual compressor circuits. The compressors are
bolted to the unit basepan. Remove the 4 bolts holding the
compressor to the basepan. Save the mounting hardware for
use with the new compressor. Carefully cut the compressor
suction and discharge lines with a tubing cutter as close to the
compressor as feasible. For dual compressor circuits, do NOT
disturb the suction line tee at the backside of the compressors.
This tee contains a special tube that is required for proper oil
return. Remove high-pressure switch and pressure transduc­er(s) if required for compressor removal. Lift one corner of the
compressor at a time and remove all the rubber mounting
grommets. Remove the old compressor from the unit.

one side of the compressor at a time, replace all of the compres­sor mounting grommets. Using new tubing or couplings as re­quired, reconnect compressor suction and discharge lines. Us­ing hardware saved, reinstall the mounting bolts and washers
through the compressor feet. Using proper techniques, braze
suction and discharge lines and check for leaks. Reconnect oil
equalization line on dual compressor circuit models.

pressure switch/internal thermostat wiring as on the old com­pressor. Refer to Fig. 27-30. Following the installation of the
new compressor, tighten all hardware to the following specifi­cations. (See Table 30.)

All models contain scroll compressors and have from

Unscrew the junction box cover bolts and disconnect the

Be sure the oil equalization line fitting is removed from the

Slide the new compressor in place on the basepan. Lifting

Reconnect the compressor power connections and high-

FASTENER RECOMMENDED TORQUE

Compressor Mounting
Bolts

Compressor Power
Connections

Compressor Ground
Terminal Connections

Oil Equalization
Line Fitting

10 to 14 ft-lb (13.5 to 18.9 N-m)

24 to 28 in.-lb (2.7- to 3.2 N-m)

14 to 18 in.-lb (1.6 to 2.0 N-m)

10 to 13 ft-lb (13.5 to 17.6 N-m)

Cooler

BRAZED-PLATE COOLER HEAT EXCHANGER RE­PLACEMENT — Brazed-plate heat exchangers cannot be
repaired if they develop a leak. If a leak (refrigerant or water)
develops, the heat exchanger must be replaced. To replace a
brazed plate heat exchanger:

1. Disconnect the liquid-in and liquid-out connections at the
heat exchanger.

2. Check that the replacement heat exchanger is the same as
the original heat exchanger. The unit insulation covers the
manufacturer’s part number. Make sure the depths of the
replacement and original cooler he at exchangers are the
same.

3. Reclaim the refrigerant from the system, and unsolder the
refrigerant-in and refrigerant-out connections.

4. Remove the old heat exchanger and the bracket that it is
mounted to. The replacement heat excha nger is supplied
attached to a new mounting bracket and is fully insulated.
It also includes a cooler heater. Use of the heater is not re­quired unless the original cooler contained a factory in­stalled heater.

5. Install the replacement heat exchanger in the unit and at­tach the mounting bracket hardware to the fan uprights
(sizes 010-030) or to the bottom bracket (sizes 032-055)
using the hardware removed in Step 4. Reconnect the
cooler heater if required.

6. Carefull y braze the refrigerant lines to the connections on
the heat exchanger. Lines should be soldered using silver
as the soldering material with a minimum of 45% silver.
Keep the temperature below 1472 F (800 C) under nor­mal soldering conditions (no vacuum) to prevent the cop­per solder of the brazed plate heat exchanger from chang­ing its structure. Failure to do so can result in internal
or external leakage at the connections which cannot be re­paired.

7. Reconnect the water/brine lines.

8. Dehydrate and recharge the unit. Check for leaks.

BRAZED-PLATE COOLER HEAT EXCHANGER
CLEANING — Brazed-plate heat exchangers must be
cleaned chemically. A professional cleaning service skilled i n
chemical cleaning should be used. Use a weak acid (5% phos­phoric acid, or if the heat exch anger is clea ned frequently, 5%
oxalic acid). Pump the cleaning solution through the
exchanger, preferably in a backflush mode. After cleaning,
rinse with large amounts of fresh water to dispose of all the
acid. Cleaning materials must be disposed of properly.

The factory-installed strainer screen in front of the water/
brine inlets of the heat exchangers should be cleaned periodi­cally, depending on condition of the chiller water/brine.

58

COMPRESSOR

COMP A1

COMP A2

COMP B1

COMP B2

BASE

Fig. 27 — Typical Compressor Mounting — All Sizes

Fig. 28 — Compressor Wiring

COMP A1

COMP A2

Fig. 29 — Compressor Location — 30RA010-030

59

LEGEND

High-Pressure Switch

HPS —

Fig. 30 — Compressor Location — 30RA032-055

Check Oil Charge —

Compressors are factory charged

with oil as shown in Table 31.

Table 31 — Oil Charge

COMPRESSOR

SM110

SM115, SM125

SM160
SM185

AMOUNT

pints (liters)

5.7 (2.7)

6.7 (3.2)

7.0 (3.3)

11.6 (5.5)

If oil is visible in the compressor sight glass, check unit for
operating readiness as described in Pre-Start-Up, System
Check section (page 74), then start the unit. Observe oil level
and add oil if required, to bring oil level in compressor
crankcase up to between

1

/4 and 3/4 of sight glass during steady

operation.
To Add Oil:

1. Check the oil level with all compressors in the circuit run­ning in a stabilized condition or immediately after com­pressor shutdown. The oil level should be at

1

/3 of the oil

sight glass immediately after shutdown.

2. Using a suitable pump, add oil while c ompressor(s) are
running through the low side ¼ in. Schraeder fitting on
the compressor. For SM1 10 models, this fitting is directly
above the suction line connection. For all other compres­sor models, this fitting is near the oil equalization line fit­ting at the same height as the suction line connection.

3. Run all compressors on the circuit for at least 15 minutes
and check the oil level.

Use only Sterling-approved compressor oil:

T otaline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PP680002

Penreco . . . . . . . . . . . . . . . . . . . . . . . . . . . .Sontex 160 LT-A

Do not reuse drained oil, and do not use any oil that has

been exposed to the atmosphere.

Condenser Section and Coils

COIL CLEANING — For standard aluminum, copper and
pre-coated aluminum fin coils, clean the coils with a vac uum
cleaner, fresh water, compressed air, or a bristle brush (not
wire). Units installed in corrosive environments should have
coil cleaning as part of a planned maintenance schedule. In this
type of application, all accumulations of dirt should be cleaned
off the coil. When condenser cleaning is complete, enter “Yes”
for coil cleaning maintenance done (CL.MN ) value under Run
Status.

Do not use high-pressure water or air to clean coils — fin
damage may result.

CLEANING E-COATED COILS — Follow the outlined pro­cedure below for proper care, cleaning and maintenance of
E-coated aluminum or copper fin coils:

Coil Maintenance and Cleaning Recommendations
tine 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.

Remove Surface Loaded Fibers

— Surface loaded fibers or
dirt should be removed with a vacuum cleaner. If a vacuum
cleaner is not available, a soft brush ma y be used. In either
case, the tool should be applied in the direction of the fins. Coil

— Rou-

surfaces can be easily damaged (fin edges bent over) if the tool
is applied across the fins.

NOTE: 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 Coil Surfaces

— Monthly cleaning with
Environmentally Sound Coil Cleaner is essential to extend the
life of coils. It is recommended that all coils, including stan­dard aluminum, pre-coated, copper/copper or E-coated coils
are cleaned with the Environmentally Sound Coil Cleaner as
described below. Coil cleaning should be part of the units regu­larly scheduled maintenance procedures to ensure long life of
the coil. Failu re to clean the coil s may result in reduced dura­bility in the environment.

Environmentally Sound Coil Cleaner is non-flammable,
hypo allergenic, non-bacterial, USDA accepted biodegradable
and 100% ecologically safe 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.

Environmentally Sound Coil Cleaner Application
Equipment

•21/2 Gallon Garden Sprayer

• Water Rinse with Low Velocity Spray Nozzle
Environmentally Sound Coil Cleaner Application

Instructions

• Although Environmentally Sound Co il Cleaner is harm-

less to humans, animals, and marine life, proper eye pro ­tection such as safety glasses is recommended during
mixing and application.

• Remove all surface loaded fibers and dirt with a vacuum

cleaner as described above.

• Thoroughly wet finned surfaces with clean water and a

low velocity garden hose being careful not to bend fins.

• Mix Environmentally Sound Coil Cleaner in a 2

1

/2 gallon
garden sprayer according to the instructions included
with the Enzyme Cleaner. The optimum solution tem­perature is 100 F.

NOTE: DO NOT USE

water in excess of 130 F as the enzy-

matic activity will be destroyed.

• Thoroughly apply Environmentally Sound Coil Cleaner
solution to all coil surfaces including finned area, tube
sheets and coil headers.

• 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.

• Ensure cleaner thoroughly penetrates deep into finned
areas.

• Interior and exterior finned areas must be thoroughly
cleaned.

• Finned surfaces should remain wet with cleaning solu­tion for 10 minutes.

• Ensure surfaces are not allowed to dry before rinsing.
Reapply cleaner as needed to ensure 10-minute satura­tion is achieved.

60

• Thoroughly rinse all surfaces with low velocity clean

PUMP
ACCESS

SERVICE
DOOR

CONTROL
ACCESS

FAN BLADE BOTTOMS
OUT ON MOTOR SHAFT

PLASTIC FAN
PROPELLER

CLEARANCE OF 0.25 INCHES
(6.4 MM) FOR STANDARD
CONDENSER FANS

FAN DECK
SURFACE

FAN ORIFICE

Fig. 31 — 30RA Access Panels

Fig. 32 — Condenser-Fan Mounting

Fig. 33 — Condenser-Fan Position (Standard Fan)

water using downward rinsing motion of water spray
nozzle. Protect fins from damage from the spray nozzle.

Harsh Chemical and Acid Cleaners — Harsh chemical,
household bleach or acid cleaners should not be used to
clean outdoor or indoors 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 Environmentally Sound Coil Cleaner as
described above.

High Velocity Water or Compressed Air

— 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. Reduced unit performance or nui­sance unit shutdown may occur.

COND E N SE R SE CT I O N — Condenser fan motors and fans
can be serviced by removal of outlet grilles or side panels. See
Fig. 31. Be sure the wire fan guard is in place over each fan be­fore starting unit. See Fig. 32 and 33 for proper fan adjustment.
Fan mounting system is designed for fan to drop all the way on
the motor shaft to be correctly l ocated in the or ifice. Tighten
fan hub securely on motor shaft with setscrews which bear
against the key. Be sure to replace the plastic fa n cap and se­cure in place with the four locki ng clip s to kee p w ater and de­bris out of shaft area.

Check Refrigerant Feed Components

THERMOSTATIC EXP ANSION VALVE (TXV) — The TXV
controls the flow of liquid refrigerant to the cooler by main­taining constant superheat of vapor leaving the cooler. There is
one valve per refrigerant circuit. The valve(s) is activated by a
temperature-sensing bulb(s) strapped to the suction line(s). For
proper TXV sensing bulb location, see Fig. 34.

The valve is factory-set to maintain between 8 and 12 F
(4.4 and 6.7 C) of superheat entering the compressor(s). Ele­vate head pressure to 280 psig (1930 kPa) by blocking the air­flow through the condenser. Check the superheat during opera­tion after conditions have stabilized. A factory-installed tem­perature well is in each suction line for this purpose. If
necessary, adjust the superheat to prevent refrigerant floodback
to the compressor. Adjust TXVs
circuit to stabilize between adjustments. Turn stem counter­clockwise to decrease superheat and clockw ise to increase s u­perheat.

FILTER DRIER — The function of t he fil ter drier is t o main­tain a clean, dry system. The moisture indicator (described
below) indicates any need to ch ange the filter drier. The filter
drier is a sealed-type drier. When the drier needs to be
changed, the entire filter drier must be replaced.

NOTE: Dual circuit (032-055 sizes) units have 1 filter drier per
circuit.

MOISTURE-LIQUID INDICA TOR — The indicator is located
immediately ahead of the TXV to provide an indication of the
refrigerant moisture content. It also provides a sight glass for
refrigerant liquid. Clear flow of liquid refri gerant (at full unit
loading) indicates sufficient charge in the system. Bubbles in the
sight glass (at full unit loading) indicate an undercharged system
or the presence of noncondensables. Moisture in t he system,
measured in parts per million (ppm), changes the color of the
indicator as follows:

Green (safe) —Moisture is below 45 ppm
Yellow-Green (caution) — 45 to 130 ppm
Yellow (wet) — above 130 ppm

1

/2 turn at a time, allowing the

The unit must be in operation at le ast 12 hours before the
moisture indicator gives an accurate reading, and must be in
contact with liquid refrigerant. At the fi rst sign of moisture in
the system, change the corresponding filter drier.

NOTE: Dual circuit (032-055 sizes) units have one indicator
per circuit.

MINIMUM LOAD VALVE — On units equipped with the
factory-installed capacity reduction option, a solenoid valve
(minimum load valve) is located between the discharge line
and the cooler entering-refrigerant line. The MBB cycles the
solenoid to perform minimum load valve function.

61

TXV SENSOR
LOCATION

Fig. 34 — Mounting Locations for TXV Sensing Bulb

TXV SENSOR
LOCATION

The amount of capacity reduction achieved by the mini­mum load valve is not adjustable. The total unit capacity with
the minimum load valve is shown in Table 7.

PRESSURE RELIEF DEVICES — All units have one pres­sure relief device per circuit located in the liquid line which re­lieves at 210 F (100 C).

Compressor and Unit Protective Devices

MANUAL STARTER — There is one manual starter per
compressor in each unit. It protects the compressor(s) against
overloading, locked rotor conditions, and primary single phas­ing. If the manual starter trips, determine the cause and correct
it before resetting.

Manual starters are factory set; field adjustment should not
be required. Manual starters are also factory installed for each
condenser fan motor and factory-installed chilled water pump.

NOTE: Two-sp eed condenser fan motors on sizes 010-018 and
032-040 have manual starters so that the motor is protected
while running in both low and high speed modes. Refer to
Appendix B for factory settings.

COMPRESSOR INTERNAL TH ERMAL PROTE CTION —
All models include internal compressor protection. Models
using the SM110 compressor (015 50 Hz and 018 60 Hz) have
internal line break overloads. All other compressor models
have internal discharge temperature thermostats that are wir ed
in series with the compressor high pre ssu re swit ch in the co m­pressor motor junction box. The thermostat opens and shuts off
the compressor if the discharge gas temperature exceeds 275 F
(135 C). The thermostat will automatically reset when the tem­perature drops below a preset level, however, the control mod­ule will keep the unit locked off until the alert condition is
reset.

Check Unit Safeties

HIGH-PRESSURE SWITCH — A high-pressure switch is
provided to protect each compressor and refrigeration system
from unsafe high pressure conditions. See Table 32 for high­pressure switch settings.

The high-pressure switch is mounted in the discharge side
of each compressor. A snubber is provided between the com­pressor discharge manifold and the high-pressure switch to pre­vent pressure pulsations from damaging the switch.

The high-pressure switch is mounted in the discharge line of
each compressor. If an unsafe, high-pressure condition should
exist, the switch opens and shuts off the affected compressor.
The compressor feedback signal to J9 of the MBB then opens
causing an alert condition. The MBB prevents the compressor
from restarting until the alert condition is reset. The switch
should open at the pressure corresponding to the appropriate
switch setting as shown in T able 32.

Table 32 — Factory Settings, High-Pressure

Switch (Fixed)

UNIT

30RA

CUTOUT CUT-IN

Psig kPa Psig kPa

426 ± 7 2937 ± 48 324 ± 20 2206 ± 138

Clear the alarm using the Scrolling Marquee display as de­scribed on page 42. The unit should restart after the compressor
anti-short-cycle delay, built into the unit control module,
expires.

PRESSURE TRANSDUCERS — Each refrigerant circuit is
equipped with a suction and discharge pressure transducer. The
transducers are NOT the same part number. The discharge
pressure transducer is the universal pressure transducer while
the suction pressure transducer is a discrete low pressure trans­ducer. These inputs to the MBB are not only used to monitor
the status of the unit, but to also maintain operation of the chill­er within the compressor manufacturer's sp ecified limits. The
input to the MBB from the suction pressure transducer is also
used to protect the compressor from operating at low pressure
conditions. In some cases, the unit may not be able to run at full
capacity. The control module will automatically reduce the ca­pacity of a circuit as needed to maintain s pecified maximum/
minimum operating pressures.

62

COOLER FREEZE-UP PROTECTION

On medium temperature brine units, the brine must be
properly mixed to prevent freezing at a temperature of at
least 15 F (8.3 C) below the leaving-fluid tem perature set
point. Failure to provide the proper brine mixture is consid­ered abuse and may void the Sterling warranty.

The Main Base Board (MBB) monitors leaving fl uid tem­perature at all times. The MBB will rapidly remove stages of
capacity as necessary to prevent freezing conditions due to the
rapid loss of load or low cooler fluid flow.

When the cooler is exposed to lower ambient temperatures
(34 F [1° C] or below), freeze-up protection is required using
inhibited ethylene glycol.

HEATER CABLE — Optional factory-installed cooler and/or
hydronic package heaters are cycled based on the input from
the outside-air temperature sensor. These heaters, when in­stalled, are designed to protect the cooler and/or hydronic pack­age from freezing down to –20 F (–29 C). Power for these heat­ers is supplied from the main unit power.

The input from the low pressure transducer provides a back­up cooler freeze protection package. The MBB shuts down the
unit when a low pressure condition exists that could cause the
cooler to freeze up.

Do not disconnect main unit power when servicing com­pressor(s) if ambient temperature is below 40 F (4.4 C).
Each compressor manual starter has a lockout feature.
Depress the Stop Button and pull the lockout tab from the
start button. Secure lock in place. If power to the unit must
be off for a prolonged period, drain the cooler, hydronic
package (if installed) and internal piping. Add glycol
according to WINTER SHUTDOWN Step 2 below.

WINTER SHUTDOWN — At the end of the cooling season:

1. Drain the water/brine from the cooler, hydronic package
(if installed) and internal piping.

2. Fill the package with at least 2 gallons (7.6 L) of ethylene
glycol or other suitable uninhibited antifreeze solution to
prevent any residual water in the cooler and hydronic
package/piping from freezing.

3. At the beginning of the next cooling season, refill the
cooler and add the recommended inhibitor.

Thermistors —

thermistors to sense temperatures used to control operation of
the chiller. Thermistors T1, T2 and T9 are identical in their
temperature and voltage drop performance. Accessory return
gas thermistors are also 5 kΩ thermistors used to troubleshoot
TXV superheat settings. Thermistor T10 has a 10 kΩ input
channel and has a different set of temperature vs. resistance and
voltage drop performance. Resistance at various temperat ures
are listed in Tables 33-36.

NOTE: For dual chiller operation, the control automatically
configures the T10 input channel to be a 5 kΩ channel. A
HH79NZ014 or HH79NZ029 thermistor should be used for
dual chiller configurations.

Thermistor pin connection points are shown in Table 2. Ther­mistor T1 is located in a well at the bottom of the brazed plate
heat exchanger for sizes 010-030 and in the leaving fluid pip­ing for sizes 032-055.

Thermistor T2 is located in a we ll at the top of the brazed
plate heat exchanger for sizes 010-030 and in the entering fluid
piping for sizes 032-055. Thermistor T9 is factory installed in

Electronic control uses up to five 5 kΩ

the compressor section behind a panel with a vent plug so that
outside air flows across the sensor tip.

REPLACING THERMISTORS T1 and T2 — Add a small
amount of thermal conductive grease to the thermistor well and
end of probe. Thermistors are friction-fit thermistors, which
must be slipped into receivers in the cooler (010-030) or fluid
piping (032-055). For sizes 032-055, tighten the retaining nut
¼ turn past finger tight. See Fig. 35.

THERMISTOR/TEMPERATURE SENSOR CHECK — A
high quality digital volt-ohmmeter is required to perform this
check.

1. Connect the digital voltmeter across the appropriate
themistor termi nals at the J8 terminal stri p on the Main
Base Board (see Fig. 36).

2. Using the voltage reading obtained, read the sensor tem­perature from Tables 33-36.

3. 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 t emperature
determined from thermistor voltage reading should be
close, ± 5° F (3° C) 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, by deter­mining the resistance with chiller 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.

Pressure Transducers —

sure transducers are installed on each circuit. No pressure
transducer calibration is required. The transducers operate on a
5 vdc supply, which is generated by the Main Base Board
(MBB). See Fig. 36 for transducer connections to the J8 con­nector on the MBB.

TROUBLESHOOTING — If a transducer is suspected of be­ing faulty, first check the supply voltage to transducer. Supply
voltage should be 5 vdc ± 0.2 v. If supply voltage is correct,
compare pressure reading displayed on the Scrolling Marquee
display module against pressure shown on a calibrated pressure
gauge. Suction pressure should be within ± 2 psig. Discharge
pressure should be within ± 5 psig. If the two readings are not
reasonably close, replace the pressure transducer.

Flow Sensor —

leaving fluid piping of all models. If the unit is equipped with
an optional hydronic system, the flow switch is inside the
pump cabinet. If nuisance trips of the sensor are occurring, fol­low the steps below to correct the situation:

1. Check to confirm that the factory installed strainer is
clean. Use the blow-down valve provided or remove the
screen and clean it. For the case of VFD controlled
pumps, ensure that the minimum speed setting has not
been changed.

2. Measure the pressure drop across the cooler or cooler/
pump system and compare this to the system requirements.

3. Verify that cable connections at the switch a nd at the te r­minal block are secure.

4. For factory-installed hydronic systems, verify that:

• All air has been purged from the system

• Circuit setter balance valve has been correctly set

5. Pump impeller has been improperly trimmed and is not
providing sufficient flow.

6. Wrong pump motor rotation. Pump must rotate clockwise
when viewed from motor end of pump.

A flow switch is factory installed in the

Suction and discharge pres-

63

TEMP

(F)

–25
–24
–23
–22
–21
–20
–19
–18
–17
–16
–15
–14
–13
–12
–11
–10

–9
–8
–7
–6
–5
–4
–3
–2
–1

0
1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58

Table 33 — 5K Thermistor Temperatures (°F) vs. Resistance/Voltage Drop

(Voltage Drop for Entering, Leaving Water and Outside-Air Thermistors T1, T2, T9)

VOLTAGE

DROP

(V)

3.699 98,010

3.689 94,707

3.679 91,522

3.668 88,449

3.658 85,486

3.647 82,627

3.636 79,871

3.624 77,212

3.613 74,648

3.601 72,175

3.588 69,790

3.576 67,490

3.563 65,272

3.550 63,133

3.536 61,070

3.523 59,081

3.509 57,162

3.494 55,311

3.480 53,526

3.465 51,804

3.450 50,143

3.434 48,541

3.418 46,996

3.402 45,505

3.386 44,066

3.369 42,679

3.352 41,339

3.335 40,047

3.317 38,800

3.299 37,596

3.281 36,435

3.262 35,313

3.243 34,231

3.224 33,185

3.205 32,176

3.185 31,202

3.165 30,260

3.145 29,351

3.124 28,473

3.103 27,624

3.082 26,804

3.060 26,011

3.038 25,245

3.016 24,505

2.994 23,789

2.972 23,096

2.949 22,427

2.926 21,779

2.903 21,153

2.879 20,547

2.856 19,960

2.832 19,393

2.808 18,843

2.784 18,311

2.759 17,796

2.735 17,297

2.710 16,814

2.685 16,346

2.660 15,892

2.634 15,453

2.609 15,027

2.583 14,614

2.558 14,214

2.532 13,826

2.506 13,449

2.480 13,084

2.454 12,730

2.428 12,387

2.402 12,053

2.376 11,730

2.349 11,416

2.323 11,112

2.296 10,816

2.270 10,529

2.244 10,250

2.217 9,979

2.191 9,717

2.165 9,461

2.138 9,213

2.112 8,973

2.086 8,739

2.060 8,511

2.034 8,291

2.008 8,076

RESISTANCE

(Ohms)

TEMP

(F)

59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98

99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142

VOLTAGE

DROP

(V)

1.982 7,686

1.956 7,665

1.930 7,468

1.905 7,277

1.879 7,091

1.854 6,911

1.829 6,735

1.804 6,564

1.779 6,399

1.754 6,238

1.729 6,081

1.705 5,929

1.681 5,781

1.656 5,637

1.632 5,497

1.609 5,361

1.585 5,229

1.562 5,101

1.538 4,976

1.516 4,855

1.493 4,737

1.470 4,622

1.448 4,511

1.426 4,403

1.404 4,298

1.382 4,196

1.361 4,096

1.340 4,000

1.319 3,906

1.298 3,814

1.278 3,726

1.257 3,640

1.237 3,556

1.217 3,474

1.198 3,395

1.179 3,318

1.160 3,243

1.141 3,170

1.122 3,099

1.104 3,031

1.086 2,964

1.068 2,898

1.051 2,835

1.033 2,773

1.016 2,713

0.999 2,655

0.983 2,597

0.966 2,542

0.950 2,488

0.934 2,436

0.918 2,385

0.903 2,335

0.888 2,286

0.873 2,239

0.858 2,192

0.843 2,147

0.829 2,103

0.815 2,060

0.801 2,018

0.787 1,977

0.774 1,937

0.761 1,898

0.748 1,860

0.735 1,822

0.723 1,786

0.710 1,750

0.698 1,715

0.686 1,680

0.674 1,647

0.663 1,614

0.651 1,582

0.640 1,550

0.629 1,519

0.618 1,489

0.608 1,459

0.597 1,430

0.587 1,401

0.577 1,373

0.567 1,345

0.557 1,318

0.548 1,291

0.538 1,265

0.529 1,240

0.520 1,214

RESISTANCE

(Ohms)

TEMP

(F)

143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225

VOLTAGE

DROP

(V)

0.511 1,190

0.502 1,165

0.494 1,141

0.485 1,118

0.477 1,095

0.469 1,072

0.461 1,050

0.453 1,029

0.445 1,007

0.438 986

0.430 965

0.423 945

0.416 925

0.408 906

0.402 887

0.395 868

0.388 850

0.381 832

0.375 815

0.369 798

0.362 782

0.356 765

0.350 750

0.344 734

0.339 719

0.333 705

0.327 690

0.322 677

0.317 663

0.311 650

0.306 638

0.301 626

0.296 614

0.291 602

0.286 591

0.282 581

0.277 570

0.272 561

0.268 551

0.264 542

0.259 533

0.255 524

0.251 516

0.247 508

0.243 501

0.239 494

0.235 487

0.231 480

0.228 473

0.224 467

0.220 461

0.217 456

0.213 450

0.210 445

0.206 439

0.203 434

0.200 429

0.197 424

0.194 419

0.191 415

0.188 410

0.185 405

0.182 401

0.179 396

0.176 391

0.173 386

0.171 382

0.168 377

0.165 372

0.163 367

0.160 361

0.158 356

0.155 350

0.153 344

0.151 338

0.148 332

0.146 325

0.144 318

0.142 311

0.140 304

0.138 297

0.135 289

0.133 282

RESISTANCE

(Ohms)

64

TEMP

(C)

–32
–31
–30
–29
–28
–27
–26
–25
–24
–23
–22
–21
–20
–19
–18
–17
–16
–15
–14
–13
–12
–11
–10

–9
–8
–7
–6
–5
–4
–3
–2
–1

10
11
12
13
14

Table 34 — 5K Thermistor Temperatures (°C) vs. Resistance/Voltage Drop

(Voltage Drop for Entering, Leaving Water and Outside-Air Thermistors T1, T2, T9)

VOLTAGE

DROP

(V)

3.705 100,260

3.687 94,165

3.668 88,480

3.649 83,170

3.629 78,125

3.608 73,580

3.586 69,250

3.563 65,205

3.539 61,420

3.514 57,875

3.489 54,555

3.462 51,450

3.434 48,536

3.406 45,807

3.376 43,247

3.345 40,845

3.313 38,592

3.281 38,476

3.247 34,489

3.212 32,621

3.177 30,866

3.140 29,216

3.103 27,633

3.065 26,202

3.025 24,827

2.985 23,532

2.945 22,313

2.903 21,163

2.860 20,079

2.817 19,058

2.774 18,094

2.730 17,184

2.685 16,325

0

2.639 15,515

1

2.593 14,749

2

2.547 14,026

3

2.500 13,342

4

2.454 12,696

5

2.407 12,085

6

2.360 11,506

7

2.312 10,959

8

2.265 10,441

9

2.217 9,949

2.170 9,485

2.123 9,044

2.076 8,627

2.029 8,231

RESISTANCE

(Ohms)

TEMP

(C)

15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61

VOLTAGE

DROP

(V)

1.982 7,855

1.935 7,499

1.889 7,161

1.844 6,840

1.799 6,536

1.754 6,246

1.710 5,971

1.666 5,710

1.623 5,461

1.580 5,225

1.538 5,000

1.497 4,786

1.457 4,583

1.417 4,389

1.378 4,204

1.340 4,028

1.302 3,861

1.265 3,701

1.229 3,549

1.194 3,404

1.160 3,266

1.126 3,134

1.093 3,008

1.061 2,888

1.030 2,773

0.999 2,663

0.969 2,559

0.940 2,459

0.912 2,363

0.885 2,272

0.858 2,184

0.832 2,101

0.807 2,021

0.782 1,944

0.758 1,871

0.735 1,801

0.713 1,734

0.691 1,670

0.669 1,609

0.649 1,550

0.629 1,493

0.610 1,439

0.591 1,387

0.573 1,337

0.555 1,290

0.538 1,244

0.522 1,200

RESISTANCE

(Ohms)

TEMP

(C)

62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98

99
100
101
102
103
104
105
106
107

VOLTAGE

DROP

(V)

0.506 1,158

0.490 1,118

0.475 1,079

0.461 1,041

0.447 1,006

0.433 971

0.420 938

0.407 906

0.395 876

0.383 836

0.371 805

0.360 775

0.349 747

0.339 719

0.329 693

0.319 669

0.309 645

0.300 623

0.291 602

0.283 583

0.274 564

0.266 547

0.258 531

0.251 516

0.244 502

0.237 489

0.230 477

0.223 466

0.217 456

0.211 446

0.204 436

0.199 427

0.193 419

0.188 410

0.182 402

0.177 393

0.172 385

0.168 376

0.163 367

0.158 357

0.154 346

0.150 335

0.146 324

0.142 312

0.138 299

0.134 285

RESISTANCE

(Ohms)

65

Table 35 — 10K Thermistor Temperature (°F) vs. Resistance/Voltage Drop

(For Thermistor T10)

TEMP

(F)

–25
–24
–23
–22
–21
–20
–19
–18
–17
–16
–15
–14
–13
–12
–11
–10

–9
–8
–7
–6
–5
–4
–3
–2
–1

0
1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60

VOLTAGE

DROP

(V)

4.758 196,453

4.750 189,692

4.741 183,300

4.733 177,000

4.724 171,079

4.715 165,238

4.705 159,717

4.696 154,344

4.686 149,194

4.676 144,250

4.665 139,443

4.655 134,891

4.644 130,402

4.633 126,183

4.621 122,018

4.609 118,076

4.597 114,236

4.585 110,549

4.572 107,006

4.560 103,558

4.546 100,287

4.533 97,060

4.519 94,020

4.505 91,019

4.490 88,171

4.476 85,396

4.461 82,729

4.445 80,162

4.429 77,662

4.413 75,286

4.397 72,940

4.380 70,727

4.363 68,542

4.346 66,465

4.328 64,439

4.310 62,491

4.292 60,612

4.273 58,781

4.254 57,039

4.235 55,319

4.215 53,693

4.195 52,086

4.174 50,557

4.153 49,065

4.132 47,627

4.111 46,240

4.089 44,888

4.067 43,598

4.044 42,324

4.021 41,118

3.998 39,926

3.975 38,790

3.951 37,681

3.927 36,610

3.903 35,577

3.878 34,569

3.853 33,606

3.828 32,654

3.802 31,752

3.776 30,860

3.750 30,009

3.723 29,177

3.697 28,373

3.670 27,597

3.654 26,838

3.615 26,113

3.587 25,396

3.559 24,715

3.531 24,042

3.503 23,399

3.474 22,770

3.445 22,161

3.416 21,573

3.387 20,998

3.357 20,447

3.328 19,903

3.298 19,386

3.268 18,874

3.238 18,384

3.208 17,904

3.178 17,441

3.147 16,991

3.117 16,552

3.086 16,131

3.056 15,714

3.025 15,317

RESISTANCE

(Ohms)

TEMP

(F)

61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98

99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

VOLTAGE

DROP

(V)

2.994 14,925

2.963 14,549

2.932 14,180

2.901 13,824

2.870 13,478

2.839 13,139

2.808 12,814

2.777 12,493

2.746 12,187

2.715 11,884

2.684 11,593

2.653 11,308

2.622 11,031

2.592 10,764

2.561 10,501

2.530 10,249

2.500 10,000

2.470 9,762

2.439 9,526

2.409 9,300

2.379 9,078

2.349 8,862

2.319 8,653

2.290 8,448

2.260 8,251

2.231 8,056

2.202 7,869

2.173 7,685

2.144 7,507

2.115 7,333

2.087 7,165

2.059 6,999

2.030 6,838

2.003 6,683

1.975 6,530

1.948 6,383

1.921 6,238

1.894 6,098

1.867 5,961

1.841 5,827

1.815 5,698

1.789 5,571

1.763 5,449

1.738 5,327

1.713 5,210

1.688 5,095

1.663 4,984

1.639 4,876

1.615 4,769

1.591 4,666

1.567 4,564

1.544 4,467

1.521 4,370

1.498 4,277

1.475 4,185

1.453 4,096

1.431 4,008

1.409 3,923

1.387 3,840

1.366 3,759

1.345 3,681

1.324 3,603

1.304 3,529

1.284 3,455

1.264 3,383

1.244 3,313

1.225 3,244

1.206 3,178

1.187 3,112

1.168 3,049

1.150 2,986

1.132 2,926

1.114 2,866

1.096 2,809

1.079 2,752

1.062 2,697

1.045 2,643

1.028 2,590

1.012 2,539

0.996 2,488

0.980 2,439

0.965 2,391

0.949 2,343

0.934 2,297

0.919 2,253

0.905 2,209

RESISTANCE

(Ohms)

TEMP

(F)

147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225

VOLTAGE

DROP

(V)

0.890 2,166

0.876 2,124

0.862 2,083

0.848 2,043

0.835 2,003

0.821 1,966

0.808 1,928

0.795 1,891

0.782 1,855

0.770 1,820

0.758 1,786

0.745 1,752

0.733 1,719

0.722 1,687

0.710 1,656

0.699 1,625

0.687 1,594

0.676 1,565

0.666 1,536

0.655 1,508

0.645 1,480

0.634 1,453

0.624 1,426

0.614 1,400

0.604 1,375

0.595 1,350

0.585 1,326

0.576 1,302

0.567 1,278

0.558 1,255

0.549 1,233

0.540 1,211

0.532 1,190

0.523 1,169

0.515 1,148

0.507 1,128

0.499 1,108

0.491 1,089

0.483 1,070

0.476 1,052

0.468 1,033

0.461 1,016

0.454 998

0.447 981

0.440 964

0.433 947

0.426 931

0.419 915

0.413 900

0.407 885

0.400 870

0.394 855

0.388 841

0.382 827

0.376 814

0.370 800

0.365 787

0.359 774

0.354 762

0.349 749

0.343 737

0.338 725

0.333 714

0.328 702

0.323 691

0.318 680

0.314 670

0.309 659

0.305 649

0.300 639

0.296 629

0.292 620

0.288 610

0.284 601

0.279 592

0.275 583

0.272 574

0.268 566

0.264 557

RESISTANCE

(Ohms)

66

TEMP

(C)

–32
–31
–30
–29
–28
–27
–26
–25
–24
–23
–22
–21
–20
–19
–18
–17
–16
–15
–14
–13
–12
–11
–10

–9
–8
–7
–6
–5
–4
–3
–2
–1

0
1
2
3
4
5
6
7
8

9
10
11
12
13
14

Table 36 — 10K Thermistor Temperature (°C) vs. Resistance/Voltage Drop

(For Thermistor T10)

VOLTAGE

DROP

(V)

4.762 200,510

4.748 188,340

4.733 177,000

4.716 166,342

4.700 156,404

4.682 147,134

4.663 138,482

4.644 130,402

4.624 122,807

4.602 115,710

4.580 109,075

4.557 102,868

4.533 97,060

4.508 91,588

4.482 86,463

4.455 81,662

4.426 77,162

4.397 72,940

4.367 68,957

4.335 65,219

4.303 61,711

4.269 58,415

4.235 55,319

4.199 52,392

4.162 49,640

4.124 47,052

4.085 44,617

4.044 42,324

4.003 40,153

3.961 38,109

3.917 36,182

3.873 34,367

3.828 32,654

3.781 31,030

3.734 29,498

3.686 28,052

3.637 26,686

3.587 25,396

3.537 24,171

3.485 23,013

3.433 21,918

3.381 20,883

3.328 19,903

3.274 18,972

3.220 18,090

3.165 17,255

3.111 16,464

RESISTANCE

(Ohms)

TEMP

(C)

15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61

VOLTAGE

DROP

(V)

3.056 15,714

3.000 15,000

2.944 14,323

2.889 13,681

2.833 13,071

2.777 12,493

2.721 11,942

2.666 11,418

2.610 10,921

2.555 10,449

2.500 10,000

2.445 9,571

2.391 9,164

2.337 8,776

2.284 8,407

2.231 8,056

2.178 7,720

2.127 7,401

2.075 7,096

2.025 6,806

1.975 6,530

1.926 6,266

1.878 6,014

1.830 5,774

1.784 5,546

1.738 5,327

1.692 5,117

1.648 4,918

1.605 4,727

1.562 4,544

1.521 4,370

1.480 4,203

1.439 4,042

1.400 3,889

1.362 3,743

1.324 3,603

1.288 3,469

1.252 3,340

1.217 3,217

1.183 3,099

1.150 2,986

1.117 2,878

1.086 2,774

1.055 2,675

1.025 2,579

0.996 2,488

0.968 2,400

RESISTANCE

(Ohms)

TEMP

(C)

62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98

99
100
101
102
103
104
105
106
107

VOLTAGE

DROP

(V)

0.940 2,315

0.913 2,235

0.887 2,157

0.862 2,083

0.837 2,011

0.813 1,943

0.790 1,876

0.767 1,813

0.745 1,752

0.724 1,693

0.703 1,637

0.683 1,582

0.663 1,530

0.645 1,480

0.626 1,431

0.608 1,385

0.591 1,340

0.574 1,297

0.558 1,255

0.542 1,215

0.527 1,177

0.512 1,140

0.497 1,104

0.483 1,070

0.470 1,037

0.457 1,005

0.444 974

0.431 944

0.419 915

0.408 889

0.396 861

0.386 836

0.375 811

0.365 787

0.355 764

0.345 742

0.336 721

0.327 700

0.318 680

0.310 661

0.302 643

0.294 626

0.287 609

0.279 592

0.272 576

0.265 561

RESISTANCE

(Ohms)

67

Strainer —

FLUID-SIDE TEMPERATURE SENSORS (T1 AND T2)

NOTE: Dimensions in ( ) are in millimeters.

Fig. 35 — Fluid-Side Temperature Sensors

(T1 and T2)

Fig. 36 — Thermistor Connections to

Main Base Board, J8 Connector

Periodic factory-installed strainer cleaning is
required. Pressure drop across strainer in excess of 3 psi
(21 kPa) indicates the need for cleaning. Normal (clean) pres­sure drop is approximately 1 psi (6.9 kPa). Open the factory­installed blowdown valve to clean the strainer. If required, shut
the chiller down and remove the strainer screen to clean. When
strainer has been cleaned, enter ‘YES’ for strainer maintenance
done (S.T .MN) [Run Status, PM].

Motormaster® V Controller —

The optional or ac­cessory Motormaster V controller uses a 0 to 5 vdc signal
input from a pressure transducer attached to the liquid line ser­vice valve gage port on each circuit. See Fig. 37. The pressure
transducer is connected to terminals 2, 5 and 6 on the c ontrol­ler. The controller is factory configured and requires no field
programming. If a situation arises where the drive does not
function properly, the information provided below and
T able 37 can be used to troubleshoot the drive.

If input power has not been applied to the drive for a period
of time exceeding three years (due to storage, etc.), the
electrolytic DC bus capacitors within the drive can change
internally, resulting in excessive leakage current. This can
result in premature failure of the capacitors if the drive is
operated after such a long period of inactivity or storage. In
order to reform the capacitors and prepare the drive for
operation after a long period of inactivity, apply input
power to the drive for 8 hours prior to actually operating
the motor. Before attempting to operate the drive, motor,
and driven equipment, be sure all procedures pertaining to
installation and wiring have been properly followed.

DO NOT connect incoming AC power to output terminals
T1, T2, and T3! Severe damage to the drive will result. Do
not continuously cycle input power to the drive more than
once every two minutes. Damage to the drive will result.

Hazard of electrical shock! Wait three minutes after discon­necting incoming power before servicing drive. Capacitors
retain charge after power is removed. Drive assembly
includes externally mounted current limiting resistors. Use
extreme caution when servicing the drive.

When configured as shown below, this equipment is
designed to start when it receives line power. Ensure that
all personnel are clear of fans and guards are installed
before applying power.

GENE RAL OPERAT ION — This control varies conde nser
fan speed based on liquid pressure. The control is a Vari able
Frequency Drive (VFD) and is only compatible with motors
rated for use with VFDs. The accompanying pressure transduc­er has a 0 to 5 v output range corresponding to a –40 to 460 psi
range. The VFD provides a 5 v output for the transducer on
pin 6.

This system is a reverse acting, proportional-integral (PI)
control. The VFD will vary the motor speed to drive the l iqui d
line pressure to the set point during ambient temperatures be­low 60 F. The set point is lower than a normal operating pres­sure during summer operation. At higher ambient tempera­tures, the fan will go to full speed (60 Hz or 50 Hz dependi ng
on model) and remain there since it can not go fast enough to

bring the pressure down to the set point. When the VFD is at
full speed, it acts just like a fixed speed fan.

When the ambient air temperature drops, a fan running at
full speed draws too much air across the condenser coil to
maintain a minimum condensing pressure/temperature. In
these conditions, the VFD will slow down and begin to main­tain a set point.

The VFD will display the set point as the de fault. The set
point is displayed in speed as Hz and is configured by the start
command jumper as detailed in Fig. 38.

Motormaster V control can also be configured to follow an
external control system to perform the PI control functions. See
configuration section for details.

The real-time feedback signal (liquid line pressure, in volts)
is displayed by viewing parameter 69. The real-time output fre­quency is displayed by viewing parameter 71.

SET POINTS — Operating modes are configured for R-22
with a set point of 135 psig on the liquid line.

INSTALLATION — See Fig. 38 for transducer wiring to the
VFD.

NOTE: The drive is phase insensitive with respect to incoming
line voltage. This means that the VF D will operate with any
phase sequence of the incoming three-phase voltage.

68

PROGRAMMING

It is strongly recommended that the user NOT change any
programming without consulting Sterling service personnel.
Unit damage may occur from improper programming.

Motormaster V control is completely configured ac cording to
the inputs provided. No additional programming is necessary.

The drive ca n display 71 program pa rameters. Parameters
50-60 are monitor functions and cannot be changed. The
remainder of the parameters can be changed after entering a
password.

T o en ter pa sswo rd an d chan ge pr og ram v alu es:

1. Press Mode.

2. Upper right decimal point blinks.

3. Display reads “00” (see Fig. 37). To enter the PRO-

GRAM mode to access the parameters, press the Mode
button (see Fig. 37). This will activate the PASSWORD
prompt (if the password has not been disabled). T he dis­play will read “00” and the upper right-hand decimal
point will be blinking.

4. Use the and buttons to scroll to the password
value (the factory default password is “111”) and press
the Mode button. Once t he correct pa sswor d value is en­tered, the display will read “P01”, which indicates that the
PROGRAM mode has been accessed at the beginning of
the parameter menu (P01 is the first parameter).

NOTE: If the display flashes “Er”, the password was incorrect,
and the process to enter the password must be repeated.

5. Press Mode to display present parameter setting.
Upper right decimal point blinks.

Use the and buttons to scroll to the desired
parameter number.

Once the desired parameter number is found, press the

Mode button to display the present parameter setting. The up­per right-hand decimal point will begin blinking, indicating
that the present parameter setting is being displayed, and that it
can be changed by using the up and down buttons. Use
and to change setting. Press Mode to store new setting.

Pressing the Mode will store the new setting and also exit

the PROGRAM mode. To change another parameter, press the
Mode key again to re-enter the PROGRAM mode (the param­eter menu will be accessed at the parameter that was last
viewed or changed before exiting). If the Mode key is pressed
within two minutes of exiting the PROGRAM mode, the pass­word is not required access the parameters. After two minutes,
the password must be entered in order to access the parameters
again.

To change password: first enter the current password then

change parameter P44 to the desired password.

To disable automatic control m ode and enter ma nual speed

control mode:

1. Change P05 to ‘01- keypad’.

2. Push UP and DOWN arrow key to set manual speed.

3. Set P05 to ‘05 - R22’ to restore automatic control.

T o provide manual start/stop control:

With power removed from VFD, remove start command
jumper and in sta ll a s wi tch b etwe en th e a ppr opr iate st art ter mi­nals as required in Fig 37.

EPM CHIP — The drive uses a electronic programming mod­ule (EPM) chip to store the program parameters. This is an EE­PROM memory chip and is accessible from the front of the
VFD. It should not be removed with power applied to the
VFD.

LIQUID LINE PRESSURE SET POINT ADJUST­MENT — Adjusting the set point is not recommended due to
possible interaction with other head pressure software algo­rithms or controls. In situations where the set point must be
changed, the set point for R-22 is found in P34. A higher value
will result in a higher liquid line set point. Example: increasing
the factory default (P34) set point from 18.0 to 19.0 will in­crease the liquid line pressure by approximately 10 psi.

LOSS OF SCN COMMUNICATIONS — Sterlco Comfort
Network (SCN) communications with external control
systems can be affected by high frequency electrical noise gen­erated by the Motormaster V control. Ensure unit is well
grounded to eliminate ground currents along communication
lines.

If communications are lost only while Motormaster V con­trol is in operation, order a signal isolator (CEAS420876-2)
and power supplies (CEAS221045-01, 2 required) for the SCN
communication line.

Fault Codes
start after a fault and will attempt to restart three times after a
fault (the drive will not restart after CF, cF, GF, F1, F2-F9, or
Fo faults). If all three restart attempts are unsuccessful, the
drive will trip into FAULT LOCKOUT (LC), which requires a
manual reset.

NOTE: Since faults may be reset as incoming power is cycled,
you may need to observe current fault code before the Sterling
unit control turns off the VFD. Most recent faults can be
accessed using parameter 50. If necessary, remove start jumper
and energize condenser fan contactor using Service Test. This
will allow programming and access to fault history.

— The drive is programmed to automatically re-

69

L1

L2

L3

Mode

Mode

T1

BUTTONS

T2

DANGER

T3

MMV
TERMINAL
BLOCK

B+

B-

DISPLAY

Fig. 37 — Motormaster® V Mode Buttons and Mode Display

1256 11

COM

+5V

Fig. 38 — Pressure Transducer and Start Command Jumper Wiring

2 14 13A 13B 13C 15 25 2 30 31 TXA

12

NOMINAL

MODE

VOLTAGE

208*/230/

1

460/575

2 208*/230 60

3 230 50

4 380/415 50

*At 208 v, the drive can run in either mode.

CONTROL INPUT

Hz

Internal PI control,

60

0-5V feedback

Internal PI control,

0-5V feedback

Internal PI control,

0-5V feedback

Internal PI control,

0-5V feedback

(PIN 5)

TB13C-TB2 None

70

START

JUMPER

TB1-TB2 None

TB13A-TB2 None

TB13B-TB2 None

SETPOINT

JUMPER

TXB

REFRIGERANT

MMV
TERMINAL
BLOCK

R-22

Table 37 — Fault Codes

FAULT CODE DESCRIPTION SOLUTION

AF High Temperature Fault: Ambient temperature is too high;

CF Control Fault: A blank EPM, or an EPM with corrupted data

cF Incompatibility Fault: An EPM with an incompatible parame-

CL CURRENT LIMIT: The output current has exceeded the

GF Data Fault: User data and OEM defaults in the EPM are

HF High DC Bus Voltage Fault: Line voltage is too high; Decel-

JF Serial Fault: The watchdog timer has timed out, indicating

LF Low DC Bus Voltage Fault: Line voltage is too low. Check line voltage — set P01 appropriately
OF Output Transistor Fault: Phase to phase or phase to ground

PF Current Overload Fault: VFD is undersized for the applica-

SF Single-phase Fault: Single-phase input power has been

F1 EPM Fault: The EPM is missing or damaged.
F2-F9, Fo Internal Faults: The control board has sensed a problem Consult factory
Drive display = 60.0 even though it

is cold outside and it should be run­ning slower

Drive display = ‘---’ even though
drive should be running

Drive display = 8.0 even though fan
should be running faster

VFD flashes 57 and LCS Feedback or speed signal lost. Drive will operate at 57 Hz

Cooling fan has failed (if equipped).

has been installed.

ter version has been installed.

CURRENT LIMIT setting (Parameter 25) and the drive is
reducing the output frequency to reduce the output current.
If the drive remains in CURRENT LIMIT too long, it can trip
into a CURRENT OVERLOAD fault (PF).

corrupted.

eration rate is too fast; Overhauling load.

that the serial link has been lost.

short circuit on the output; Failed output transistor; Boost
settings are too high; Acceleration rate is too fast.

tion; Mechanical problem with the driven equipment.

applied to a three-phase drive.

Feedback signal is above set point Check for proper set point

Start jumper is missing Replace start jumper. See section above

Feedback signal is below set point and fan is at minimum
speed

until reset or loss of start command. Resetting requires
cycling start command (or power).

Check cooling fan operation

Perform a factory reset using Parameter 48 —
PROGRAM SELECTION.

Either remove the EPM or perform a factory
reset (Parameter 48) to change the parameter
version of the EPM to match the parameter
version of the drive.

Check for loose electrical connections.
Check for faulty condenser fan motor.
Check Parameter P25 from Table 38 is set cor­rectly.

Restore factory defaults P48, see section
above. If that does not work, replace EPM.

Check line voltage — set P01 appropriately

Check serial connection (computer)
Check settings for PXX.
Check settings in communication software to
match PXX.

Reduce boost or increase acceleration values.
If unsuccessful, replace drive.

Check line voltage — set P01 appropriately
Check for dirty coils
Check for motor bearing failure

Check input power phasing

Check liquid line pressure

Check for proper set point
Check liquid line pressure

In stand alone mode: Check transducer wiring
and feedback voltage. Feedback voltage dis­played on P-69. Pin 6 should be 5 v output.
Pin 5 (feedback) should be somewhere
between 0 and 5 v.

Manual Reset

— If fault condition has been removed, cycle

power to the chiller to reset the VFD.
Troubleshooting

— Troubleshooting the Motormaster® V
control requires a combination of observing system ope ration
and VFD information. The drive provides 2 kinds of trouble­shooting modes: a status matrix using the 3-digit display
(P57, P58) and real time monitoring of key inputs and outputs.
The collective group is displayed through parameters
50-60 and all values are read-only.

• P50: FAULT HISTORY — Last 8 faults

• P51: SOFTWARE version

• P52: DC BUS VOLTAGE — in percent of nominal.

Usually rated input voltage x 1.4

• P53: MOTOR VOLAGE — in percent of rated output

voltage

• P54: LOAD — in percent of drives rated output current

rating

• P55: VDC INPUT — in percent of maximum input:

100 will indicate full scale which is 5 v

• P56 4-20 mA INPUT — in percent of maximum input.

20% = 4 mA, 100% = 20 mA

Manual Starter Trip

— If the VFD manual starter (MS-FC­HS, MS-FC-A1 or MS-FC-B1 depending on model) trips,
locate the inrush current protectors (3 round black disks per
motor) and verify their resistance. For units operating at 208 v
or 230 v, these devices should measure approximately 7 ohms.
For all other voltages, they should measure approximately
20 ohms. Check value with mating plug disconnected, power
to chiller off and at ambient temperature (not hot immediately
after stopping VFD). These are standard resistances at 77 F
(25 C). Resistance values decrease at higher temperatures and
increase at lower temperatures.

71

Table 38 — Motormaster® V Program Parameters for Operating Modes

PARAMETERS DESCRIPTION

P01
P02
P03
P04

P05

P06
P08
P09
P10
P11
P12
P13
P14
P15
P16
P17
P19
P20
P21
P22
P23
P24
P25
P26
P27
P28
P29
P30
P31
P32
P33

P34

P35

P36
P37
P38
P39
P40
P41
P42
P43
P44

P45

P46

P47
P48
P61
P62
P63
P64
P65
P66
P67
P68

LEGEND

NA —
PID —
TB —

Not Applicable
Proportional Integral Derivative
Terminal Block

Line Voltage: 01 = low line, 02 = high line 01 02 01 02
Sterlco Freq: 01 = 4 kHz, 02 = 6 kHz, 03 = 8 kHz 01 01 01 01
Startup mode: flying restar t 06 06 06 06
Stop mode: coast to stop 01 01 01 01
Standard Speed source: 01= keypad,

04=4-20mA (NO PI), 05= R22, 06=R134a
TB-14 output: 01 = none 01 01 01 01
TB-30 output: 01 = none 01 01 01 01
TB-31 Output: 01 = none 01 01 01 01
TB-13A function sel: 01 = none 01 01 01 01
TB-13B function sel: 01 = none 01 01 01 01
TB-13C function sel: 01 = none 01 01 01 01
TB-15 output: 01 = none 01 01 01 01
Control: 01 = Terminal strip 01 01 01 01
Serial link: 02 = enabled 9600,8,N,2 with timer 02 02 02 02
Units editing: 02 = whole units 02 02 02 02
Rotation: 01 = forward only, 03 = reverse only 01 01 01 01
Acceleration time: 10 sec 10 10 10 10
Deceleration time: 10 sec 10 10 10 10
DC brake time: 0 0 0 0 0
DC BRAKE VOLTAGE 0% 0 0 0 0
Min freq = 8 Hz ~ 100 – 160 rpm 8 8 8 8
Max freq 60 60 50 50
Current limit: (%) 125 110 125 110
Motor overload: 100 100 100 100 100
Base freq: 60 or 50 Hz 60 60 50 50
Fixed boost: 0.5% at low frequencies 0.5 0.5 0.5 0.5
Accel boost: 0% 0 0 0 0
Slip compensation: 0% 0 0 0 0
Preset spd #1: speed if loss of control signal 57 57 47 47
Preset spd #2: 0 0 0 0 0
Preset spd #3: 0 0 0 0 0
Preset spd 4 default — R22 set point.

TB12-2 open
Preset spd 5 default — R134a set point.

TB12-2 closed
Preset spd 6 default 0 0 0 0
Preset spd 7 default 0 0 0 0
Skip bandwidth 0 0 0 0
Speed scaling 0 0 0 0
Frequency scaling 50 or 60 Hz 60 60 50 50
Load scaling: default (not used so NA) 200 200 200 200
Accel/decel #2: default (not used so NA) 60 60 60 60
Serial address 1 1 1 1
Password:111 111 111 111 111
Speed at min signal: 8 Hz; used when PID

mode is disabled and 4-20mA input is at 4 mA
Speed at max feedback: 60 or 50 Hz. Used

when PID disabled and 4-20mA input is at 20 mA
Clear history? 01 = maintain. (set to 02 to clear) 01 01 01 01
Program selection: Program 1 – 12 01 02 03 04
PI Mode: 05= reverse, 0-5V, 01 = no PID 05 05 05 05
Min feedback = 0 (0V *10) 0 0 0 0
Max feedback = 50 (5V * 10) 50 50 50 50
Proportional gain = 4% 4 4 4 4
Integral gain = .2 .2 .2 .2 .2
PI acell/decel (set point change filter) = 5 5 5 5 5
Min alarm 0 0 0 0
Max alarm 0 0 0 0

MODE

1

05 05 05 05

18.0 18.0 18.0 18.0

12.6 12.6 12.6 12.6

8888

60 60 50 50

MODE

2

MODE

3

MODE

4

72

REPLACING DEFECTIVE MODULES — The Comfort-

™

Link

replacement modules are shown in Table 39. If the Main
Base Board (MBB) has been replaced, verify that all configura­tion data is correct. Follow the Configuration mode table and
verify that all items under sub-modes UNIT, OPT1 and OPT2
are correct. Any additional field-installed accessories or op­tions (RSET, SLCT sub-modes) should also be verified as well
as any specific time and maintenance schedules.

Refer to the Start-Up Checklist for 30RA Liquid Chillers
(completed at time of original start-up) found in the job folder.
This information is needed later in this procedure. If the check­list does not exist, fill out the current information in the Config­uration mode on a new checklist. Tailor the various options and
configurations as needed for this particular installation.

Electrical shock can cause personal injury. Disconnect all
electrical power before servicing.

1. Check that all power to unit is off. Carefully disconnect
all wires from the defective module by unplugging its
connectors.

2. Remove the defective module by removing its mounting
screws with a Phillips screwdriver, and removing the
module from the control box. Save the screws later use.

3. Verify that the instance jumper (MBB) or address switch­es (all other modules) exactly match the settings of the
defective module.

NOTE: Handle boards by mounting standoffs only to avoid
electrostatic discharge.

4. Package the defective module in the carton of the new
module for return to Sterling.

5. Mount the new module in the unit’s control box using a
Phillips screwdriver and the screws saved in Step 2.

6. Reinstall all module connectors. For accessory Navigator
replacement, make sure the plug is installed at TB3 in the
LEN connector.

7. Carefully check all wiring connections before restoring
power.

8. Verify the ENABLE/OFF/REMOTE CONTACT switch
is in the OFF position.

9. Restore control power. Verify that all modul e red LEDs
blink in unison. Verify that all green LEDs are blinking
and that the Scrolling Marquee or Navigator display is
communicating correctly.

10. Veri fy all configuration information, settings, set points
and schedules. Return the ENABLE/OFF/REMOTE
CONT ACT switch to its previous position.

Table 39 — Replacement Modules

MODULE

Main Base

Board (MBB)

Scrolling

Marquee

Display

Energy

Management

Module

(EMM)

Navigator

Display

REPLACEMENT PART

NO. (with Software)

30RA501102 HK50AA029

HK50AA031 HK50AA030

30GT515218 HK50AA028

HK50AA033 N/A

Hydronic Package —

If the unit is equipped with a

REPLACEMENT PART

NO. (without Software)

factory-installed hydronic package, consult the information be­low for proper maintenance and service. In addition to this

information, each factory-installed hydronic package is sup­plied with a packet of information supplied by the manufactur­er, Bell & Gossett. Sterling/Sterlco strongly recommends
that this information be thoroughly reviewed prior to operation
of the chiller.

PUMP PERFORMANCE CHECK — The factory-installed
pumps in the 30RA units are shipped with a single impeller
size available for that pump. The pump was selected based on
the flow and head requirements as provided to Sterling. It is not
uncommon for actual pump duty to be different than what was
anticipated at time of selection. In many cases, it may be desir­able to make some field modifications to obtain optimum
pump performance.

Before any pump modifications are made, it is recommend­ed that actual pump performance be verified and compa red to
the applicable pump curve. See base unit installation instruc­tions. This can be done in a variety of ways:

1. If pump impeller diameter is known:
a. Connect a differential pressure gage across the

pump at the ports provided on the pump volutes.

b. Read GPM from applicable impeller curve.

2. If pump impeller diameter is not known:

If pump impeller diameter has been trimmed and the size
is not known, it is necessary to determine which impeller
curve to read.

The easiest way to confirm pump performance is to
“dead-head” the pump and read the differential pressure
across the pressure ports on the pump. “Dead-heading”
can be done by shutting the circuit setter valve on the dis­charge side of the pump.

NOTE: Although not all pumps can be safely “dead­headed”, centrifugal pumps (such as on the 30RA units)
can be “dead-headed” for short amounts of time. It is rec­ommended to keep the time short due to excessive heat
build-up in the pump.

Since the “dead-head” condition is a no-flow condition,
the head will correspond to the intersection of an impel ­ler curve with the vertical a xis of the pump chart. The
correct impeller diameter is that which corresponds to the
measured h ea d.

3. Once the impeller diameter is known, proceed as in
Step 1.

4. Water flow rate can be determined by using a differential
pressure gage with the Bell & Gossett circuit setter bal­ance valve calculator. (This information is also provided
in the installation instructions.) This method will not di­rectly measure pressure differential seen by the pump, but
can be used to “double-check” the pump measurement.

5. Verify that cable connections at the switch a nd at the te r­minal block are secure.

6. For factory-installed hydronic system, verify that:

• All air has been purged from the system.

• Circuit setter balance valve has been correctly set.

7. Pump impeller has been improperly trimmed and is not
providing sufficient flow.

8. Wrong pump motor rotation. Pump must rotate clockwise
when viewed from motor end of pump.

PUMP MODIFICATIONS AND IMPELLER TRIMMING
— See applicable section in the Installation instructions.

RESET OF CHILLER WATER FLOW — S ee applicable sec­tion in the Installation instructions.

CHANGING OF PUMP SEALS — See Bell & Gossett ser­vice instruction manual provided with the hydronic package.

73

MAINTENANCE

Recommended Maintenance Schedule —

lowing are only recommended guidelines. Jobsite conditions
may dictate that maintenance schedule is performed more often
than recommended.

Routine:
For machines with E-coat Condenser Coils:

• Check condenser coils for debris, clean as necessary
with Sterling approved coil cleaner.

• Periodic clean water rinse, especially in coastal and
industrial applications.

Every month:

• Check condenser coils for debris, clean as necessary
with Sterling approved coil cleaner.

• Check moisture indicating sight glass for possible refrig­erant loss and presence of moisture.

Every 3 months (for all machines):

• Check refrigerant charge.

• Check all refrigerant joints and valves for refrigerant
leaks, repair as necessary.

• Check chilled water flow switch operation.

• Check condenser coils for debris, clean as necessary
with Sterling approved coil cleaner.

• Check all condenser fans for proper operation.

• Check compressor oil level.

• Check crankcase heater operation.

Every 12 months (for all machines):

• Check all electrical connections, tighten as necessary.

• Inspect all contactors and relays, replace as necessary.

• Check accuracy of thermistors, replace if greater than
± 2° F (1.2° C) variance from calibrated thermometer.

• Obtain and test an oil sample. Change oil only if
necessary.

• Check to be sure that the proper concentration of anti­freeze is present in the chilled water loop, if applicable.

• Verify that the chilled water loop is properly treated.

• Check refrigerant filter driers for excessive pressure
drop, replace as necessary.

• Check chilled water strainers, clean as necessary.

• Check cooler heater operation, if equipped.

• Check condition of condenser fan blades and that they
are securely fastened to the motor shaft.

• Perform Service Test to confirm operation of all
components.

• Check for excessive cooler approach (Leaving Chilled
Water Temperature — Saturated Suction Temperature)
which may indicate fouling. Clean cooler vessel if
necessary.

The fol-

PRE-START-UP

IMPORTANT: Before beginning Pre-Start-Up or Start-Up,
complete Start-Up Checklist for 30RA Liquid Chiller at
end of this publication (page CL-1 to CL-8). The Checklist
assures proper start-up of a unit, and provides a record of
unit condition, application requirements, system informa­tion, and operation at initial start-up.

Do not attempt to start the chiller until following checks

have been completed.

System Check

1. Check all auxiliary components, such as chilled fluid
pumps, air-handling equipment, or other equipment to
which the chiller supplies liquid. Consult manufacturer's
instructions. V e rify that any pump interlock contacts have
been properly installed. If the unit If the unit has

field-installed accessories, be sure all are properly in­stalled and wired correctly. Refer to unit wiring diagrams.

2. Use the Scrolling Marquee display to adjust the Cooling
Set Point.

3. Fill chilled fluid circuit with clean water (with recom­mended inhibitor added) or other non-corrosive fluid to
be cooled. Bleed all air out of the high points of the sys­tem. If chilled water is to be maintained at a temperature
below 40 F (4.4 C) or outdoor temperatures are expected
to be below 32 F (0° C), a brine of sufficient concentra­tion must be used to prevent freeze-up at anticipated
suction temperatures. See Table 40.

4. Check tightness of all electrical connections.

5. Oil should be visible in the compressor sightglass(es).
See Fig. 39. An acceptable oil level in the compressors is
from ¼ to ¾ of sight glass. Adjust the oil level as re­quired. See Check Oil Charge section on page 60 for
Sterling approved oils.

6. Electrical power source must agree with unit nameplate.

7. All condenser fan and factory installed hydronic package
pump motors are three phase. Check for proper rotation
of condenser fans first BEFORE attempting to start
pumps or compressors. To reverse rotation, interchange
any two of the main incoming power leads.

8. Be sure system is fully charged with refrigerant (see
Check Refrigerant Charge section on page 75).

9. If unit is a brine unit, check to ensure proper brine con­centration is used to prevent freezing.

10. Veri fy proper operation of cooler and hydronic package
heaters (if installed). Heat ers operat e at the same voltage
as the main incoming power supply and are single phase.
Heater current is approximately .4 amps for 380, 400, 460
and 575 v units. Heater current is approximately .8 amps
for 230 v units.

Table 40 — Minimum Cooler Flow Rates and

Minimum Loop Volume

UNIT SIZE

30RA

010
015
018
022
025
030
035
040
042
045
050
055

COOLER MINIMUM

FLOW

Gpm L/s Gal. L

12 .76 40 151.2
16 1.01 55 207.9
19 1.20 48 181.4
26 1.64 65 245.7
29 1.83 71 268.3
33 2.08 82 309.3
42 2.65 102 393.1
45 2.80 113 449.8
48 3.02 119 427.1
52 3.28 129 487.6
57 3.59 142 536.6
65 4.10 163 616.1

MINIMUM COOLER

LOOP VOLUME

START-UP AND OPERATION

NOTE: Refer to Start-Up Checklist on pages CL-1 to CL-8.

Actual Start-Up —

Actual start-up should be done only

under supervision of a qualified refrigeration mechanic.

1. Be sure all service valves are open.

2. Using the Scrolling Marquee display, set leaving-fluid set
point (CSP.1) [Set Point, COOL]. No cooling range ad­justment is necessary.

3. Start chilled fluid pump (if not configured for cooler
pump control).

4. Turn ENABLE/OFF/REMOTE CONTACT switch to
ENABLE position.

74

COMPRESSOR OIL
SIGHT GLASS

Fig. 39 — Compressor Connections and Oil Sight Glass Location

5. Allow unit to operate and confirm that everything is func­tioning properly. Check to see that leaving fluid tempera­ture agrees with leaving set point (CSP.1 or CSP.2), or if
reset is used, with the control point (CTPT) [Run Status,
VIEW].

6. Check the c o o l er le av i n g c h il le d w a te r te m p e r at u r e to see
that it remains well above 32 F (0° C), or the brine freez­ing point if the unit is a medium temperature brine unit.

7. Recheck compressor oil level (see Check Oil Charge
section).

Check Refrigerant Charge —

All 30RA units are
shipped with a complete operating charge of R-22 and should
be under sufficient pressure to conduct a leak test after installa­tion. If there is no system pressure, admit nitrogen until a pres­sure is observed and then proceed to test for leaks. After leaks
are repaired, the system must be dehydrated.

All refrigerant charging should be done through the ¼-in.
Schraeder connection on the liquid line. Do NOT add refriger­ant charge through the low-pressure side of the system. If com­plete charging is required, weigh in the appropriate charge for
the circuit as shown on the unit nameplate. If partial charging is
required, operate circuit at full load and use an accurate tem­perature sensor on the liquid line as it enters the T XV. Use the
Temperatures mode on the Scrolling Marquee display to show
the circuit saturated condensing temperature (SCT.A or
SCT.B). Charging is most accurate at satur ated discharge tem­peratures of 120 to 125 F (49 to 52 C). Block condenser airflow
as required to reach this temperature range. Add refrigerant un­til the system subcooling (SCT.A or SCT.B minus liquid line
temperature entering TXV) is approximately 15 to 17 F (–9.4
to –8.3 C). Refrigerant VAPOR only may be added to a circuit
through the

1

/4-in. suction Schraeder connection on the com­pressor. This connection is located in line and to the left of the
compressor junction box for the SM110 compressors and to the

lower right of the compressor junction box for all other com­pressor models.

Never charge liquid into low-pressure side of system. Do
not overcharge. Overcharging results in higher discharge
pressure, possible compressor damage, and higher power
consumption. During charging or removal of refrigerant, be
sure water is continuously circulating through the cooler to
prevent freezing. Damage caused by freezing is considered
abuse and may void the Sterling warranty.

Operating Limitations

TEMPERATURES (See Table 41 for 30RA Standard Tem­perature Limits)

Do not operate with cooler leaving chiller water (fluid)
temperature (LCWT) below 40 F (4.4 C) for the standard
units, or below 15 F (–9.4 C) for units factory built for
medium temperature brine.

High Cooler Leaving Chilled Water (Fluid) Temperatures
(LCWT) — During start-up with cooler LCWT above approx­imately 60 F (16 C), the unit expansion valve will limit suction
pressure to approximately 90 psig (620 kPa) to avoid overload­ing the compressor.

Low Cooler LCWT
no lower than 40 F (4.4 C). If the unit is the factory-installed
optional medium temperature brine unit, the cooler LCWT can
go down to 15 F (–9.4 C).

— For standard units, the LCWT must be

75

Table 41 — Temperature Limits for

Standard 30RA Units

UNIT SIZE 30RA 010-030 032-055

Temperature F C F C

Maximum Ambient
Temperature

Minimum Ambient
Temperature

Maximum Cooler EWT*

Maximum Cooler LWT

Minimum Cooler LWT†

LEGEND

EWT —
LW T —

*For sustained operation, EWT should not exceed 85 F (29.4 C).
†Unit requires modification below this temperature.

Entering Fluid (Water) Temperature
Leaving Fluid (Water) Temperature

120 49 120 49

45 7 32 0

95 35 95 35
70 21 70 21

40 4.4 40 4.4

LOW-AMBIENT OPERA TION — If operating temperatures
below 45 F (7 C) for sizes 010-030 or below 32 F (0° C) for
sizes 032-055 are expected, accessory Motormaster® V con­trol must be installed. Refer to separate installation instructions
for operation using this accessory. Contact your Sterling repre­sentative for details.

2. Determine maximum deviation from average voltage:
(AB) 243 – 239 = 4 v

(BC) 239 – 236 = 3 v
(AC) 239 – 238 = 1 v

Maximum deviation is 4 v.

3. Determine percent voltage imbalance:

% Voltage Imbalance = 100 x

4

239

= 1.7%

This voltage imbalance is satisfactory as it is below the

maximum allowable of 2%.

IMPORTANT: If the supply voltage phase imbalance is
more than 2%, contact your local electric utility company
immediately. Do not operate unit until imbalance condition
is corrected.

Control Circuit Power

— Power for the control circuit is
supplied from the main incoming power through a factory­installed control power transformer (TRAN1) for all mode ls.
Field wiring connections are made to either terminal block
TB5 or TB6.

Brine duty application (below 40 F [4.4 C] LCWT) for
chiller normally requires factory modification. Contact
your Sterling representative for applicable LCWT range for
standard water-cooled chiller in a specific application.

VOLTAGE — ALL UNITS
Main Power Supply

— Minimum and maximum acceptable

supply voltages are listed in the Installation Instructions.

Unbalanced 3-Phase Supply Voltage — Never operate a motor
where a phase imbalance between phases is greater than 2%.

T o determine percent voltage imbalance:

max voltage deviation

% Voltage Imbalance = 100 x

from avg voltage

average voltage

The maximum voltage deviation is the largest difference
between a voltage measurement across 2 legs and the average
across all 3 legs.

Example: Supply voltage is 240-3-60.

AB = 243 v
BC = 236 v
AC = 238 v

1. Determine average voltage:

Average voltage =

243 + 236 + 238

3

717

=

3

= 239

OPERATION SEQUENCE

During unit off cycle, the control monitors the outdoor air
temperature. If the ambient temperature drops below 40 F
(4.4 C), cooler and hydronic system heaters (if either are facto­ry installed) are energized. If power is maintained to the chiller
and the EMERGENC Y ON/O FF sw it ch i s left in the OFF po ­sition, these heaters are also energized.

The unit is started by putting the ENABLE/OFF/REMOTE
CONTACT switch in the ENABLE or REMOTE CONTACT
position. When the unit receives a call for cooling (either from
the internal control or SCN network command or remote con­tact closure), the unit stages up in capacity to maintain the leav­ing fluid set point. The first compressor starts 1
after the call for cooling.

The lead circuit can be specifically designated on all models
or selected based on compressor run hours and starts depend­ing on field configuration. The unit control will override this
selection under certain starting conditions to properly maintain
oil return to the compressors. In general, on dual compressor
circuits, the control will most often start the A1 or B1 compres­sor first, especially after long off periods. The MBB controls
fan stages to maintain the head pressure set point and will auto­matically adjust unit capacity as required to keep compressors
from operating outside of the specified envelope. There are no
pumpout or pumpdown sequences on these chillers.

For all units, if temperature reset is being used, the unit con­trols to a higher leaving-fluid temperature as the building load
reduces. If demand limit is used, the unit may temporarily be
unable to maintain the desired leaving-fluid temperature be­cause of imposed power limitations. Loading sequence for
compressors is shown in Tables 6 and 7.

1

/2 to 3 minutes

76

APPENDIX A

SCN Tables

A_UNIT (General Unit Parameters)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

Control Mode 0 = Test

Occupied No/Yes OCC N
SCN Chiller Start/Stop CHIL_S_S Y
Low Sound Active No/Yes LSACTIVE N
Alarm State Normal/Alert/Alarm ALM N
Active Demand Limit 0 to 100 % DEM_LIM Y
Override Modes in Effect No/Yes MODE N
Percent Total Capacity 0 to 100 % CAP_T N
Requested Stage 0 to 99 STAGE N
Active Set Point –20 to 70
Control Point –20 to 70
Entering Fluid Temp snnn.n
Leaving Fluid Temp snnn.n
Emergency Stop Enable/Emstop Enable EMSTOP Y
Minutes Left for Start 00:00 to 15:00 minutes MIN_LEFT N
PUMPS
Cooler Pump Relay 1 Off/On COOLPMP1 N
Cooler Pump Relay 2 Off/On COOLPMP2 N
Cooler Pump 1 Interlock Open/Close PMP1_FBK N
Cooler Pump 2 Interlock Open/Close PMP2_FBK N
Cooler Flow Switch Open/Close COOLFLOW N
Rotate Cooler Pumps Now No/Yes ROT_PUMP

1 = Local Off
2 = SCN Off
3 = Clock Off
4 = Emergency Stop
5 = Local On
6 = SCN On
7 = Clock On
8 = Heat Enabled
9 = Pump Delay

°°°°

FSP N

°°°°

F CTRL_PNT Y

°°°°

FEWT N

°°°°

FLWT N

STAT N

Heat/Cool Select Heat/Cool HC_SEL N

CIRCADIO (Circuit A Discrete Inputs/Outputs)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

CIRC. A DISCRETE OUTPUTS
Compressor A1 Relay On/Off K_A1_RLY N
Compressor A2 Relay On/Off K_A2_RLY N
Minimum Load Valve Relay On/Off MLV_RLY N

CIRC. A DISCRETE INPUTS
Compressor A1 Feedback On/Off K_A1_FBK N
Compressor A2 Feedback On/Off K_A2_FBK N

CIRCA_AN (Circuit A Analog Parameters)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

CIRCUIT A ANALOG VALUES
Percent Total Capacity 0-100 % CAPA_T N
Percent Available Cap. 0-100 % CAPA_A N
Discharge Pressure nnn.n PSIG DP_A N
Suction Pressure nnn.n PSIG SP_A N
Calculated HP Setpoint A nnn.n
Saturated Condensing Tmp snnn.n
Saturated Suction Temp snnn.n
Compr Return Gas Temp snnn.n
Suction Superheat Temp snnn.n

°°°°

FHSP_AN

°°°°

FTMP_SCTAN

°°°°

F TMP_SSTA N

°°°°

FTMP_RGTAN

∆∆∆∆

FSH_AN

77

CIRCBDIO (Circuit B Discrete Inputs/Outputs)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

CIRC. B DISCRETE OUTPUTS
Compressor B1 Relay On/Off K_B1_RLY N
Compressor B2 Relay On/Off K_B2_RLY N
Minimum Load Valve Relay On/Off MLV_RLY N

CIRC. B DISCRETE INPUTS
Compressor B1 Feedback On/Off K_B1_FBK N
Compressor B2 Feedback On/Off K_B2_FBK N

CIRCB_AN (Circuit B Analog Parameters)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

CIRCUIT B ANALOG VALUES
Percent Total Capacity 0-100 % CAPB_T N
Percent Available Cap. 0-100 % CAPB_A N
Discharge Pressure nnn.n PSIG DP_B N
Suction Pressure nnn.n PSIG SP_B N
Calculated HP Setpoint B nnn.n
Saturated Condensing Tmp snnn.n
Saturated Suction Temp snnn.n
Compr Return Gas Temp snnn.n
Suction Superheat Temp snnn.n

°°°°

FHSP_BN

°°°°

FTMP_SCTBN

°°°°

F TMP_SSTB N

°°°°

FTMP_RGTBN

∆∆∆∆

FSH_BN

OPTIONS (Unit Parameters)

DESCRIPTION VALUE UNITS POINT NAME FORCEABLE

FA NS
Fan 1 Relay Off/On FAN_1 N
Fan 2 Relay Off/On FAN_2 N
Cooler/Pump Heater Off/On COOL_HTR N

UNIT ANALOG VALUES
Cooler Entering Fluid snnn.n
Cooler Leaving Fluid snnn.n
Lead/Lag Leaving Fluid snnn.n

TEMPERATURE RESET
4-20 mA Reset Signal nn.n mA RST_MA N
Outside Air Temperature snnn.n
Space Temperature snnn.n

DEMAND LIMIT
4-20 mA Demand Signal nn.n mA LMT_MA N
Demand Limit Switch 1 Off/On DMD_SW1 N
Demand Limit Switch 2 Off/On DMD_SW2 N
SCN Loadshed Signal 0 = Normal

1 = Redline
2 = Loadshed

MISCELLANEOUS
Heat Request Off/On HEAT_REQ N
Dual Setpoint Switch Off/On DUAL_IN N
Cooler LWT Setpoint snnn.n
Ice Done Off/On ICE_DONE N

°°°°

F COOL_EWT N

°°°°

F COOL_LWT N

°°°°

FDUAL_LWTN

°°°°

FOAT Y

°°°°

FSPT Y

DL_STAT N

°°°°

FLWT_SPN

78

ALARMDEF (Alarm Definition Table)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Alarm Routing Control 00000000 00000000 ALRM_CNT
Equipment Priority 0 to 7 4 EQP_TYPE
Comm Failure Retry Time 1 to 240 10 min RETRY_TM
Re-alarm Time 1 to 255 30 min RE-ALARM
Alarm System Name XXXXXXXX CHILLER ALRM_NAM

BRODEFS (Broadcast POC Definition Table)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

SCN Time/Date Broadcast Yes/No No SCNBC
SCN OAT Broadcast Yes/No No OATBC

Global Schedule Broadcast Yes/No No GSBC
SCN Broadcast Ack’er Yes/No No SCNBCACK
Daylight Savings Start:

Month 1 to 12 4 STARTM
Week 1 to 5 1 STARTW
Day 1 to 7 7 STARTD
Minutes to Add 0 to 99 60 min MINADD

Daylight Savings Stop

Month 1 to 12 10 STOPM
Week 1 to 5 5 STOPW
Day 1 to 7 7 STOPD
Minutes to Subtract 0 to 99 60 min MINSUB

DISPLAY (Marquee Display SETUP)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Service Password nnnn 1111 PASSWORD
Password Enable Enable/Disable Enable PASS_EBL
Metric Display Off/On Off DISPUNIT
Language Selection 0 = ENGLISH

1 = FRANCAIS
2 = ESPANOL
3 = PORTUGUES

0LANGUAGE

DUALCHIL (Dual Chiller Configuration Settings)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

LEAD/LAG
Lead/Lag Chiller Enable Enable/Dsable Dsable LL_ENA
Master/Slave Select Master/Slave Master MS_SEL
Slave Address 0 to 239 2 SLV_ADDR
Lead/Lag Balance Select 0 = None 0 LL_BAL
Lead/Lag Balance Delta 40 to 400 168 hours LL_BAL_D
Lag Start Delay 0 to 30 5 minutes LL_DELAY
Parallel Configuration Yes Yes PARALLEL

79

OPTIONS1 (Options 1 Configuration)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Cooler Fluid 1 = Water

2 = Med. Brine
Minimum Load Vlv Select No/Yes No MLV_FLG
Return Gas Sensor Enable Dsable/Enable Dsable RGT_ENA
Motormaster Select No/Yes No MTR_TYPE
Cooler Pump Control Off/On Off CPC
Cooler Pump 1 Enable No/Yes No PMP1_ENA
Cooler Pump 2 Enable Dsable/Enable Dsable PMP2_ENA
Cooler Pmp Periodic Strt No/Yes No PUMP_PST
Cooler Pump Select 0 = Automatic

1 = Pump 1

2 = Pump 2
Cooler Pump Shutdown Dly 0 to 10 1 minutes PUMP_DLY
Pump Changeover Hours 10 to 2000 500 hours PMP_DLTA
EMM Module Installed No/Yes No EMM_BRD

1FLUIDTYP

0 PMP_SLCT

OPTIONS2 (Options 2 Configuration)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Control Method 0 = Switch

Loading Sequence Select 1 = Equal Loading

Lead/Lag Circuit Select 0 = Automatic

Cooling Setpoint Select 0 = Single

Ramp Load Select Enable/Dsable Enable RAMP_EBL
Heat Cool Select Cool/Heat Cool HEATCOOL
High LCW Alert Limit 2 to 60 60.0
Minutes off time 0 to 15 0 min DELAY
Deadband Multiplier 1.0 to 4.0 2.0 Z_GAIN
Ice Mode Enable Enable/Dsable Dsable ICE_CNFG
Close Control Select Enable/Dsable Dsable CLS_CTRL
Low Sound Mode Select 0 = Disabled

Low Sound Start Time 00:00 to 23:59 00:00 LS_START
Low Sound End Time 00:00 to 23:59 00:00 LS_END
Low Sound Capacity Limit 0 to 100 100 % LS_LIMIT
Enable Short Loop Gain Enable/Dsable Enable SAGENABL

2 = Occupancy
3 = SCN

2 = Staged Loading

1 = Circuit A Leads
2 = Circuit B Leads

1 = Dual, remote switch controlled
2 = Dual SCN occupancy
3 = 4-20 mA input

1 = Fan only
2 = Capacity/Fans

0 CONTROL

1 SEQ_TYP

0LEAD_TYP

0CLSP_TYP

∆∆∆∆

F LCW_LMT

1LS_MODE

80

RESETCON (Temperature Reset and Demand Limit)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

COOLING RESET
Cooling Reset Type 0 = No Reset

4-20 MA RESET
4-20 – Degrees Reset –30 to 30 0.0

REMOTE RESET
Remote – No Reset Temp 0 to 125 125.0
Remote – Full Reset Temp 0 to 125 0.0
Remote – Degrees Reset –30 to 30 0.0

RETURN TEMPERATURE RESET
Return – No Reset Temp 0 to 125 10.0
Return – Full Reset Temp 0 to 125 0.0
Return – Degrees Reset –30 to 30 0.0

DEMAND LIMIT
Demand Limit Select 0 = None

Demand Limit at 20 mA 0 to 100 100 % DMT20MA
Loadshed Group Number 0 to 99 0 SHED_NUM
Loadshed Demand Delta 0 to 60 0 % SHED_DEL
Maximum Loadshed Time 0 to 120 60 minutes SHED_TIM
Demand Limit Switch 1 0 to 100 80 % DLSWSP1
Demand Limit Switch 2 0 to 100 50 % DLSWSP2

1 = 4-20 mA input
2 = External temp – OAT
3 = Return Fluid
4 = External temp - SPT

1 = External switch input
2 = 4-20 mA input
3 = Loadshed

0 CRST_TYP

∆∆∆∆

F 420_DEG

°°°°

FREM_NO

°°°°

FREM_FULL

∆∆∆∆

FREM_DEG

∆∆∆∆

FRTN_NO

∆∆∆∆

FRTN_FULL

∆∆∆∆

FRTN_DEG

0DMD_CTRL

SCHEDOVR (Timed Override Setup)

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Schedule Number 0 to 99 1 SCHEDNUM
Override Time Limit 0 to 4 0 hours OTL
Timed Override Hours 0 to 4 0 hours OVR_EXT
Timed Override No/Yes No TIMEOVER

SETPOINT

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

COOLING
Cooling Setpoint 1 –20 to 70 44.0
Cooling Setpoint 2 –20 to 70 44.0
ICE Setpoint –20 to 32 32.0

RAMP LOADING
Cooling Ramp Loading 0.2 to 2.0 1.0 CRAMP

Brine Freeze Point –20 to 34 34.0

°°°°

FCSP1

°°°°

FCSP2

°°°°

FCSP3

°°°°

F BRN_FRZ

81

UNIT

DESCRIPTION VALUE DEFAULT UNITS POINT NAME

Compressor A1 Size 8 to 15

Compressor A2 Size 0 to 15

Compressor B1 Size 0 to 15

Compressor B2 Size 0 to 15

60 Hz: 010-10; 015-15;
018-9; 022-9; 025-13;
030-15; 035-9; 040-13;
045-10; 050-13; 055-15
50 Hz: 010-11; 015-7;
018-9; 022-11; 025-13;
032-8; 035-13; 042-11;
045-13

60 Hz: 018-9; 022-13;
025-13; 030-15; 035-13;
040-13;
045-13; 050-13; 055-15
50 Hz: 015-7; 018-9; 022­11; 025-13; 032-11; 035­13; 042-11; 045-13

60 Hz: 035-15; 040-15;
045-10; 050-13; 055-15
50 Hz: 032-13; 035-13;
042-11; 045-13

60 Hz: 045-13; 050-13;
055-15
50 Hz: 042-11; 045-13

Suction Superheat Setpt 10 to 40 15 SH_SP
Refrigerant 1 = R22 1 REFRIG_T
Fan Staging Select 1 = 1 Fan

2 = 2 Fans
3 = 3 Fans
4 = 4 Fans

1 = One Fan (010-018)
2 = Two Fans (022-030)
3 = Three Fans (032-040)
4 = Four Fans (042-055)

SIZE_A1

SIZE_A2

SIZE_B1

SIZE_B2

FAN _T YP E

MAINTENANCE

ALARMS: Maintenance Display

DESCRIPTION VALUE POINT NAME

Active Alarm #1 Axxx or Txxx ALARM01C
Active Alarm #2 Axxx or Txxx ALARM02C
Active Alarm #3 Axxx or Txxx ALARM03C
Active Alarm #4 Axxx or Txxx ALARM04C
Active Alarm #5 Axxx or Txxx ALARM05C
Active Alarm #6 Axxx or Txxx ALARM06C
Active Alarm #7 Axxx or Txxx ALARM07C
Active Alarm #8 Axxx or Txxx ALARM08C
Active Alarm #9 Axxx or Txxx ALARM09C
Active Alarm #10 Axxx or Txxx ALARM10C
Active Alarm #11 Axxx or Txxx ALARM11C
Active Alarm #12 Axxx or Txxx ALARM12C
Active Alarm #13 Axxx or Txxx ALARM13C
Active Alarm #14 Axxx or Txxx ALARM14C
Active Alarm #15 Axxx or Txxx ALARM15C
Active Alarm #16 Axxx or Txxx ALARM16C
Active Alarm #17 Axxx or Txxx ALARM17C
Active Alarm #18 Axxx or Txxx ALARM18C
Active Alarm #19 Axxx or Txxx ALARM19C
Active Alarm #20 Axxx or Txxx ALARM20C
Active Alarm #21 Axxx or Txxx ALARM21C
Active Alarm #22 Axxx or Txxx ALARM22C
Active Alarm #23 Axxx or Txxx ALARM23C
Active Alarm #24 Axxx or Txxx ALARM24C
Active Alarm #25 Axxx or Txxx ALARM25C

82

CURRMODS: Maintenance Display

DESCRIPTION VALUE POINT NAME

FSM controlling Chiller On/Off MODE_1
WSM controlling Chiller On/Off MODE_2
Master/Slave control On/Off MODE_3
Ramp Load Limited On/Off MODE_5
Timed Override in effect On/Off MODE_6
Low Cooler Suction TempA On/Off MODE_7
Low Cooler Suction TempB On/Off MODE_8
Slow Change Override On/Off MODE_9
Minimum OFF time active On/Off MODE_10
Dual Setpoint On/Off MODE_13
Temperature Reset On/Off MODE_14
Demand/Sound Limited On/Off MODE_15
Cooler Freeze Protection On/Off MODE_16
Low Temperature Cooling On/Off MODE_17
High Temperature Cooling On/Off MODE_18
Making ICE On/Off MODE_19
Storing ICE On/Off MODE_20
High SCT Circuit A On/Off MODE_21
High SCT Circuit B On/Off MODE_22
Minimum Comp. On Time On/Off MODE_23
Pump Off Delay Time On/Off MODE_24
Low Sound Mode On/Off MODE_25
Short Loop Override On/Off MODE_26

DUALCHIL: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Dual Chiller Link Good? Yes/No DC_LINK
Master Chiller Role Stand Alone,

Slave Chiller Role Stand Alone,

Lead Chiller Ctrl Point snnn.n
Lag Chiller Ctrl Point snnn.n
Control Point snnn.n
Cool EnteringFluid-Slave snnn.n
Cool Leaving Fluid-Slave snnn.n
Cooler Entering Fluid snnn.n
Cooler Leaving Fluid snnn.n
Lead/Lag Leaving Fluid snnn.n
Percent Avail.Capacity 0-100 % CAP_A
Percent Avail.Cap.Slave 0-100 % CAP_A_S
Lag Start Delay Time hh:mm LAGDELAY
Load/Unload Factor snnn.n SMZ
Load/Unload Factor-Slave snnn.n SMZSLAVE
Lead SMZ Clear Commanded Yes/No LEADSMZC
Lag- SMZ Clear Commanded Yes/No LAG_SMZC
Lag Commanded Off? Yes/No LAG_OFF
Dual Chill Lead CapLimit 0-100 % DCLDCAPL
Dual Chill Lag CapLimit 0-100 % DCLGCAPL

Lead Chiller,

Lag Chiller

Lead Chiller,

Lag Chiller

MC_ROLE

SC_ROLE

°°°°

FLEAD_CP

°°°°

FLAG_CP

°°°°

F CTRL_PNT

°°°°

FCOOLEWTS

°°°°

F COOLLWTS

°°°°

F COOL_EWT

°°°°

FCOOL_LWT

°°°°

F DUAL_LWT

83

LEARNFNS: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Fan 1 Delta SCT point 1 snnn.n
Fan 1 Delta SCT point 2 snnn.n
Fan 1 Delta SCT point 3 snnn.n
Fan 1 Delta SCT point 4 snnn.n
Fan 1 Delta SCT point 5 snnn.n
Fan 2 Delta SCT point 1 snnn.n
Fan 2 Delta SCT point 2 snnn.n
Fan 2 Delta SCT point 3 snnn.n
Fan 2 Delta SCT point 4 snnn.n
Fan 2 Delta SCT point 5 snnn.n
SCT Delta for Comp A1 snnn.n
SCT Delta for Comp A2 snnn.n
SCT Delta for Comp B1 snnn.n
SCT Delta for Comp B2 snnn.n
SAGP for Compressor A1 nn.n SAGA1P
SAGM for Compressor A1 nn.n SAGA1M
SAGP for Compressor A2 nn.n SAGA2P
SAGM for Compressor A2 nn.n SAGA2M
SAGP for Compressor B1 nn.n SAGB1P
SAGM for Compressor B1 nn.n SAGB1M
SAGP for Compressor B2 nn.n SAGB2P
SAGM for Compressor B2 nn.n SAGB2M

°°°°

FF1DLTA1

°°°°

FF1DLTA2

°°°°

FF1DLTA3

°°°°

FF1DLTA4

°°°°

FF1DLTA5

°°°°

FF2DLTA1

°°°°

FF2DLTA2

°°°°

FF2DLTA3

°°°°

FF2DLTA4

°°°°

FF2DLTA5

°°°°

F A1SCTDT

°°°°

F A2SCTDT

°°°°

F B1SCTDT

°°°°

F B2SCTDT

LOADFACT: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

CAPACITY CONTROL
Load/Unload Factor snnn.n SMZ
Control Point snnn.n
Entering Fluid Temp snnn.n
Leaving Fluid Temp snnn.n

Ramp Load Limited On/Off MODE_5
Slow Change Override On/Off MODE_9
Cooler Freeze Protection On/Off MODE_16
Low Temperature Cooling On/Off MODE_17
High Temperature Cooling On/Off MODE_18
Minimum Comp. On Time On/Off MODE_23

°°°°

F CTRL_PNT

°°°°

FEWT

°°°°

FLWT

OCCUPANCY SUPERVISORY (OCCDEFM): Maintenance Display

DESCRIPTION VALUE POINT NAME

Current Mode (1=Occup.) 0/1 MODE
Current Occup. Period # 0-8 PER-NO
Timed-Override in Effect Yes/No OVERLAST
Time-Override Duration 0-4 hours OVR_HRS
Current Occupied Time hh:mm STRTTIME
Current Unoccupied Time hh:mm ENDTIME
Next Occupied Day NXTOCDAY
Next Occupied Time hh:mm NXTOCTIM
Next Unoccupied Day NXTUNDAY
Next Unoccupied Time hh:mm NXTUNTIM
Previous Unoccupied Day PRVUNDAY
Previous Unoccupied Time hh:mm PRVUNTIM

84

PM-COIL: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Coil Cleaning Srvc Inter nnnnnn hours SI_COIL
Coil Service Countdown nnnnnn hours CL_CDOWN
Coil Cleaning Maint.Done Yes/No CL_MAINT
Coil Cleaning Maint.Date mm/dd/yy hh:mm COIL_PM0
Coil Cleaning Maint.Date mm/dd/yy hh:mm COIL_PM1
Coil Cleaning Maint.Date mm/dd/yy hh:mm COIL_PM2
Coil Cleaning Maint.Date mm/dd/yy hh:mm COIL_PM3
Coil Cleaning Maint.Date mm/dd/yy hh:mm COIL_PM4

PM-PUMP: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Pump Service Interval nnnnnn hours SI_PUMPS
Pump 1 Service Countdown nnnnnn hours P1_CDOWN
Pump 1 Maintenance Done Yes/No P1_MAINT
Pump 2 Service Countdown nnnnnn hours P2_CDOWN
Pump 2 Maintenance Done Yes/No P2_MAINT
Pump 1 Maintenance Date mm/dd/yy hh:mm PMP1_PM0
Pump 1 Maintenance Date mm/dd/yy hh:mm PMP1_PM1
Pump 1 Maintenance Date mm/dd/yy hh:mm PMP1_PM2
Pump 1 Maintenance Date mm/dd/yy hh:mm PMP1_PM3
Pump 1 Maintenance Date mm/dd/yy hh:mm PMP1_PM4
Pump 2 Maintenance Date mm/dd/yy hh:mm PMP2_PM0
Pump 2 Maintenance Date mm/dd/yy hh:mm PMP2_PM1
Pump 2 Maintenance Date mm/dd/yy hh:mm PMP2_PM2
Pump 2 Maintenance Date mm/dd/yy hh:mm PMP2_PM3
Pump 2 Maintenance Date mm/dd/yy hh:mm PMP2_PM4

PM-STRN: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Strainer Srvc Interval nnnnnn hours SI_STRNR
Strainer Srvc Countdown nnnnnn hours ST_CDOWN
Strainer Maint. Done Yes/No ST_MAINT
Strainer Maint. Date mm/dd/yy hh:mm STRN_PM0
Strainer Maint. Date mm/dd/yy hh:mm STRN_PM1
Strainer Maint. Date mm/dd/yy hh:mm STRN_PM2
Strainer Maint. Date mm/dd/yy hh:mm STRN_PM3
Strainer Maint. Date mm/dd/yy hh:mm STRN_PM4

85

RUNTEST: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Percent Total Capacity nnn % CAPA_T
Percent Available Cap. nnn % CAPA_A
Discharge Pressure nnn.n psig DP_A
Suction Pressure nnn.n psig SP_A
Calculated HP Setpoint A nnn.n
Saturated Condensing Tmp nnn.n
Saturated Suction Temp nnn.n
Compr Return Gas Temp nnn.n
Suction Superheat Temp nnn.n ^F SH_A
Compressor A1 Relay On/Off K_A1_RLY
Compressor A2 Relay On/Off K_A2_RLY
Minimum Load Valve Relay On/Off MLV_RLY
Compressor A1 Feedback On/Off K_A1_FBK
Compressor A2 Feedback On/Off K_A2_FBK
Percent Total Capacity nnn % CAPB_T
Percent Available Cap. nnn % CAPB_A
Discharge Pressure nnn.n psig DP_B
Suction Pressure nnn.n psig SP_B
Calculated HP Setpoint B nnn.n
Saturated Condensing Tmp nnn.n
Saturated Suction Temp nnn.n
Compr Return Gas Temp nnn.n
Suction Superheat Temp nnn.n ^F SH_B
Compressor B1 Relay On/Off K_B1_RLY
Compressor B2 Relay On/Off K_B2_RLY
Minimum Load Valve Relay On/Off MLV_RLY

°°°°

FHSP_A

°°°°

FTMP_SCTA

°°°°

F TMP_SSTA

°°°°

FTMP_RGTA

°°°°

FHSP_B

°°°°

FTMP_SCTB

°°°°

F TMP_SSTB

°°°°

FTMP_RGTB

Compressor B1 Feedback On/Off K_B1_FBK
Compressor B2 Feedback On/Off K_B2_FBK
Fan 1 Relay On/Off FAN_1
Fan 2 Relay On/Off FAN_2

Outside Air Temperature nnn.n
Space Temperature nnn.n
Cooler Pump Relay 1 On/Off COOLPMP1
Cooler Pump Relay 2 On/Off COOLPMP2
Cooler Pump 1 Interlock Open/Closed PMP1_FBK
Cooler Pump 2 Interlock Open/Closed PMP2_FBK
Cooler Entering Fluid nnn.n
Cooler Leaving Fluid nnn.n
Compressor A1 Size nnn tons SIZE_A1
Compressor A2 Size nnn tons SIZE_A2
Compressor B1 Size nnn tons SIZE_B1
Compressor B2 Size nnn tons SIZE_B2
Cooler Flow Switch On/Off COOLFLOW

°°°°

FOAT

°°°°

FSPT

°°°°

F COOL_EWT

°°°°

F COOL_LWT

86

STRTHOUR: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Machine Operating Hours nnnnnn hours HR_MACH
Machine Starts nnnnnn CY_MACH

Circuit A Run Hours nnnnnn hours HR_CIRA

Compressor A1 Run Hours nnnnnn hours HR_A1
Compressor A2 Run Hours nnnnnn hours HR_A2

Circuit B Run Hours nnnnnn hours HR_CIRB

Compressor B1 Run Hours nnnnnn hours HR_B1
Compressor B2 Run Hours nnnnnn hours HR_B2

Circuit A Starts nnnnnn CY_CIRA

Compressor A1 Starts nnnnnn CY_A1
Compressor A2 Starts nnnnnn CY_A2

Circuit B Starts nnnnnn CY_CIRB

Compressor B1 Starts nnnnnn CY_B1
Compressor B2 Starts nnnnnn CY_B2

PUMP HOURS
Pump 1 Run Hours nnnnnn hours HR_PUMP1
Pump 2 Run Hours nnnnnn hours HR_PUMP2

TESTMODE: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

Service Test Mode On/Off NET_CTRL
Compressor A1 Relay On/Off S_A1_RLY
Compressor A2 Relay On/Off S_A2_RLY
Compressor B1 Relay On/Off S_B1_RLY
Compressor B2 Relay On/Off S_B2_RLY
Fan 1 Relay On/Off S_FAN_1
Fan 2 Relay On/Off S_FAN_2
Cooler Pump Relay 1 On/Off S_CLPMP1
Cooler Pump Relay 2 On/Off S_CLPMP2
Minimum Load Valve Relay On/Off S_MLV
Remote Alarm Relay On/Off S_ALM

VERSIONS: Maintenance Display

DESCRIPTION VERSION VALUE

MBB CESR131279- nn-nn
EMM CESR131174- nn-nn
MARQUEE CESR131171- nn-nn
NAVIGATOR CESR130227- nn-nn

87

WSMDEFME: Maintenance Display

DESCRIPTION VALUE UNITS POINT NAME

WSM Active? Yes WSMSTAT

Chilled water temp snn.n
Equipment status On CHLRST

Commanded state Enable

CHW setpoint reset value nn.n ^F CHWRVAL
Current CHW setpoint snn.n

Dsable

None

F CHWTEMP

°

CHLRENA

F CHWSTPT

°

88

APPENDIX B

FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMP,

UNIT

VOLTAGE

SIZE

30RA

V-P H -H z

575-3-60 -100 15.5 — 3.6 — 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 24.2 — 5.5 — 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 37.1 — 9.1 — 2.5 4.8 6.2 6.2 8.9 —

208/230-3-60 -500 41.2 — 10.1 — 2.5 5.3 7.0 7.0 9.8 —

010

460-3-60 -600 19.2 — 4.6 — 1.8 2.8 3.1 3.1 4.4 —
230-3-50 -800 40.9 — 7.6 — 2.5 3.4 4.8 4.8 6.1 —

380/415-3-50 -900 23.8 — 4.6 — 1.8 2.0 2.9 2.9 3.7 —

575-3-60 -100 22.7 — 3.6 — 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 36.1 — 5.5 — 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 52.6 — 9.1 — 2.5 4.8 6.2 6.2 8.9 —

208/230-3-60 -500 58.4 — 10.1 — 2.5 5.3 7.0 7.0 9.8 —

015

460-3-60 -600 28.6 — 4.6 — 1.8 2.8 3.1 3.1 4.4 —
230-3-50 -800 31.1 31.1 7.6 — 2.5 3.4 4.8 4.8 6.1 —

380/415-3-50 -900 17.2 17.2 4.6 — 1.8 2.0 2.9 2.9 3.7 —

575-3-60 -100 13.6 13.6 3.6 — 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 21 21 5.5 — 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 31.9 31.9 9.1 — 2.5 4.8 6.2 6.2 8.9 —

208/230-3-60 -500 35.4 35.4 10.1 — 2.5 5.3 7.0 7.0 9.8 —

018

460-3-60 -600 16.9 16.9 4.6 — 1.8 2.8 3.1 3.1 4.4 —
230-3-50 -800 33.7 33.7 7.6 — 2.5 3.4 4.8 4.8 6.1 —

380/415-3-50 -900 18.7 18.7 4.6 — 1.8 2.0 2.9 2.9 3.7 —

575-3-60 -100 14.6 19.9 — 2.3 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 22.7 31.7 — 3.5 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 35.3 44 — 5.8 2.5 4.8 6.2 6.2 8.9 —

208/230-3-60 -500 39.2 49 — 7.0 2.5 5.3 7.0 7.0 9.8 —

022

460-3-60 -600 17.5 24.2 — 2.9 1.8 2.8 3.1 3.1 4.4 —
230-3-50 -800 40.9 40.9 — 4.6 2.5 3.4 4.8 4.8 6.1 —

380/415-3-50 -900 23.8 23.8 — 3.7 1.8 2.0 2.9 2.9 3.7 —

575-3-60 -100 19.9 19.9 — 2.3 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 31.7 31.7 — 3.5 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 44 44 — 5.8 2.5 4.8 6.2 6.2 8.9 —

208/230-3-60 -500 49 49 — 7.0 2.5 5.3 7.0 7.0 9.8 —

025

460-3-60 -600 24.2 24.2 — 2.9 1.8 2.8 3.1 3.1 4.4 —
230-3-50 -800 49.9 49.9 — 4.6 2.5 3.4 4.8 4.8 6.1 —

380/415-3-50 -900 29 29 — 3.7 1.8 2.0 2.9 2.9 3.7 —

575-3-60 -100 22.7 22.7 — 2.3 1.8 1.9 2.5 2.5 3.6 —
380-3-60 -200 36.1 36.1 — 3.5 1.8 2.9 3.7 3.7 5.4 —
230-3-60 -400 52.6 52.6 — 5.8 2.5 4.8 6.2 6.2 8.9 —

030

208/230-3-60 -500 58.4 58.4 — 7.0 2.5 5.3 7.0 7.0 9.8 —

460-3-60 -600 28.6 28.6 — 2.9 1.8 2.8 3.1 3.1 4.4 —

VOLTAGE

SERIES

OVERLOAD

RELAY (CA1)

SETTING FOR

COMPRESSOR

A1

AND MANUAL STARTERS

OVERLOAD

RELAY (CA2)

SETTING FOR

COMPRESSOR

A2

MANUAL

STARTER

SETTING FOR

FANS FC-HS/LS

MANUAL

STARTER

SETTING FOR

FANS FC-A1/A2

MANUAL

STARTER
SETTING FOR
CHC (Heaters)

MANUAL STARTER

(CWP1, CWP2) SETTINGS

FOR PUMP OPTIONS

(Model Number Position 9)

A/F B/G C/H D/J E/K

89

FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMP,

AND MANUAL STARTERS (cont)

UNIT

VOLTAGE

SIZE

30RA

V-P H -H z

230-3-50 -800 31.4 40.9 49.9 — 7.6 4.6 2.5 — 4.8 — 6.1 10.4

032

380/415-3-50 -900 17.4 23.8 29 — 4.6 3.7 1.8 — 2.9 — 3.7 6.4

575-3-60 -100 14.6 19.9 22.7 — 3.6 2.3 1.8 — 2.5 — 3.6 6.0
380-3-60 -200 22.7 31.7 36.1 — 5.5 3.5 1.8 — 3.7 — 5.4 9.1
230-3-60 -400 35.3 44 52.6 — 9.1 5.8 2.5 — 6.2 — 8.9 15.1

208/230-3-60 -500 39.2 49 58.4 — 10.1 7.0 2.5 — 7.0 — 9.8 16.7

035

460-3-60 -600 17.5 24.2 28.6 — 4.6 2.9 1.8 — 3.1 — 4.4 7.6
230-3-50 -800 49.9 49.9 49.9 — 7.6 4.6 2.5 — 4.8 — 6.1 10.4

380/415-3-50 -900 29 29 29 — 4.6 3.7 1.8 — 2.9 — 3.7 6.4

575-3-60 -100 19.9 19.9 22.7 — 3.6 2.3 1.8 — 2.5 — 3.6 6.0
380-3-60 -200 31.7 31.7 36.1 — 5.5 3.5 1.8 — 3.7 — 5.4 9.1
230-3-60 -400 44 44 52.6 — 9.1 5.8 2.5 — 6.2 — 8.9 15.1

040

208/230-3-60 -500 49 49 58.4 — 10.1 7.0 2.5 — 7.0 — 9.8 16.7

460-3-60 -600 24.2 24.2 28.6 — 4.6 2.9 1.8 — 3.1 — 4.4 7.6
230-3-50 -800 40.9 40.9 40.9 40.9 — 4.6 2.5 — 4.8 — 6.1 10.4

042

380/415-3-50 -900 23.8 23.8 23.8 23.8 — 3.7 1.8 — 2.9 — 3.7 6.4

575-3-60 -100 15.5 19.9 15.5 19.9 — 2.3 1.8 — 2.5 — 3.6 6.0
380-3-60 -200 24.2 31.7 24.2 31.7 — 3.5 1.8 — 3.7 — 5.4 9.1
230-3-60 -400 37.1 44 37.1 44 — 5.8 2.5 — 6.2 — 8.9 15.1

208/230-3-60 -500 41.2 49 41.2 49 — 7.0 2.5 — 7.0 — 9.8 16.7

045

460-3-60 -600 19.2 24.2 19.2 24.2 — 2.9 1.8 — 3.1 — 4.4 7.6
230-3-50 -800 49.9 49.9 49.9 49.9 — 4.6 2.5 — 4.8 — 6.1 10.4

380/415-3-50-90029292929— 3.7 1.8 — 2.9 — 3.7 6.4

575-3-60 -100 19.9 19.9 19.9 19.9 — 2.3 1.8 — 2.5 — 3.6 6.0
380-3-60 -200 31.7 31.7 31.7 31.7 — 3.5 1.8 — 3.7 — 5.4 9.1
230-3-60 -400 44 44 44 44 — 5.8 2.5 — 6.2 — 8.9 15.1

050

208/230-3-60-50049494949— 7.0 2.5 — 7.0 — 9.8 16.7

460-3-60 -600 24.2 24.2 24.2 24.2 — 2.9 1.8 — 3.1 — 4.4 7.6
575-3-60 -100 22.7 22.7 22.7 22.7 — 2.3 1.8 — 2.5 — 3.6 6.0
380-3-60 -200 36.1 36.1 36.1 36.1 — 3.5 1.8 — 3.7 — 5.4 9.1
230-3-60 -400 52.6 52.6 52.6 52.6 — 5.8 2.5 — 6.2 — 8.9 15.1

055

208/230-3-60 -500 58.4 58.4 58.4 58.4 — 7.0 2.5 — 7.0 — 9.8 16.7

460-3-60 -600 28.6 28.6 28.6 28.6 — 2.9 1.8 — 3.1 — 4.4 7.6

VOLTAGE

SERIES

OVERLOAD

RELAY (CA1)

SETTING FOR

COMPRESSOR

A1

OVERLOAD

RELAY (CA2)

SETTING FOR

COMPRESSOR

A2

OVERLOAD

RELAY (CB1)

SETTING FOR

COMPRESSOR

B1

OVERLOAD

RELAY (CB2)

SETTING FOR

COMPRESSOR

B2

MANUAL

STARTER

FOR FANS

FC-HS/LS

MANUAL

STARTER

SETTING

FOR

FC-A1/A2

MANUAL
STARTER
SETTING
FOR CHC
(Heaters)

MANUAL STARTER

SETTINGS FOR

PUMP OPTIONS

(Model Number

Position 9)

A/F B/G C/H D/J E/K

90

APPENDIX C

Building Interface —

faced with multi-vendor control systems through 3 levels of
inter-operability using BAClink, DataPort™, or DataLink™
controls. BAClink controls function as a gateway between a
SCN and a BACnet™ system to facilitate the passing of data
from the SCN to BACnet. The Sterlco DataPort control is an
interface device that allows other HVAC control systems to
“read only” values in system elements connected to a SCN

The 30RAN chiller can be inter-

DataPort, DataLink, BAClink Object Definition

communication bus. The Sterlco DataLink control is an inter­face device that allows other HVAC control systems to read
and change (“read/write”) values in system elements connected
to a SCN bus. Both DataPort and DataLink controls request
data from a specified SCN system element and translate this
data into ASCII characters off network. Information fr om the
30RAN chiller control to support interface are listed in the
following tables.

SCN TABLE

NAME

A_UNIT

CIRCADIO

CIRCA_AN

CIRCBDIO

CIRCB_AN

LEGEND

Not Available

NA —

Read Only

RO —

Read/Write

RW —

DESCRIPTION STATUS UNITS POINT DataPort DataLink BAClink

GENERAL PARAMETERS
Control Mode
Occupied
SCN Chiller
Low Sound Active
Alarm State
Active Demand Limit
Override Modes In Effect
Percent Total Capacity
Requested Stage
Active Setpoint
Control Point
Entering Fluid Temp
Leaving Fluid Temp
Emergency Stop
Minutes Left for Start
PUMPS
Cooler Pump Relay 1
Cooler Pump Relay 2
Cooler Pump 1 Interlock
Cooler Pump 2 Interlock
Cooler Flow Switch
Lead Pump
Rotate Cooler Pumps Now

Heat/Cool Select
CIRC. A DISCRETE OUTPUTS

Compressor A1 Relay
Compressor A2 Relay
Minimum Load Valve Relay

CIRC. A DISCRETE INPUTS
Compressor A1 Feedback
Compressor A2 Feedback

CIRCUIT A ANALOG VALUES
Percent Total Capacity
Percent Available Cap.
Discharge Pressure
Suction Pressure
Calculated HP Setpoint A
Saturated Condensing Tmp
Saturated Suction Temp
Compr Return Gas Temp
Suction Superheat Temp

CIRC. B DISCRETE OUTPUTS
Compressor B1 Relay
Compressor B2 Relay
Minimum Load Valve Relay

CIRC. B DISCRETE INPUTS
Compressor B1 Feedback
Compressor B2 Feedback

CIRCUIT B ANALOG VALUES
Percent Total Capacity
Percent Available Cap.
Discharge Pressure
Suction Pressure
Calculated HP Setpoint B
Saturated Condensing Tmp
Saturated Suction Temp
Compr Return Gas Temp
Suction Superheat Temp

(Modes 0-9)

No/Yes

Start/Stop

No/Yes

Normal/Alert/Alarm

0 to 100

No/Yes

0 to 100

–20 to 70 (–28.8 to 21.1)
–20 to 70 (–28.8 to 21.1)

0 to 99

snnn.n
snnn.n

Enable/Emstop

00:00 to 15:00

Off/On

Off/On
Open/Close
Open/Close

Off/On

0, 1, 2

No/Yes

Heat/Cool

Off/On

Off/On

Off/On

Off/On

Off/On

0 to 100
0 to 100

nnn.n
nnn.n

nnn.n
snnn.n
snnn.n
snnn.n
snnn.n

Off/On
Off/On
Off/On

Off/On
Off/On

0 to 100
0 to 100

nnn.n

nnn.n

nnn.n
snnn.n
snnn.n
snnn.n
snnn.n

STAT

OCC
CHIL_S_S
LSACTIVE

%

%

°F (°C)
°F (°C)
°F (°C)
°F (°C)

Minutes

%

%
PSIG (KPA)
PSIG (KPA)

°F (°C)
°F (°C)
°F (°C)
°F (°C)

dF (dC)

%

%
PSIG (KPA)
PSIG (KPA)

°F (°C)
°F (°C)
°F (°C)
°F (°C)

dF (dC)

NOTE: In order to write to any point with DataLink or BAClink con­trols, the machine must be configured for SCN control. CTRL

Control Method

to 3 = SCN Control.

ALM

DEM_LIM

MODE

CAP_T

STAGE

SP

CTRL_PNT

EWT

LWT

EMSTOP

MIN_LEFT

COOLPMP1
COOLPMP2

PMP1_FBK
PMP2_FBK

COOLFLOW

LEADPUMP
ROT_PU MP

HC_SEL

K_A1_RLY
K_A2_RLY

MLV_RLY

K_A1_FBK
K_A2_FBK

CAPA_T
CAPA_A

DP_A

SP_A

HSP_A

TMP_SCTA

TMP_SSTA

TMP_RGTA

SH_A

K_B1_RLY
K_B2_RLY

MLV_RLY

K_B1_FBK
K_B2_FBK

CAPB_T

CAPB_A

DP_B

SP_B

HSP_B
TMP_SCTB
TMP_SSTB

TMP_RGTB

SH_B

(Configuration mode, sub-mode OPT2) must be set

RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO

RO
RO
RO
RO
RO
RO
RO

RO

RO
RO
RO

RO
RO

RO
RO
RO
RO
RO
RO
RO
RO
RO

RO
RO
RO

RO
RO

RO
RO
RO
RO
RO
RO
RO
RO
RO

RO
RO

RW

RO
RO

RW

RO
RO
RO
RO

RW

RO
RO

RW

RO

RO
RO
RO
RO
RO
RO
RO

RO

RO
RO
RO

RO
RO

RO
RO
RO
RO
RO
RO
RO
RO
RO

RO
RO
RO

RO
RO

RO
RO
RO
RO
RO
RO
RO
RO
RO

RO
RO

RW

NA
RO

RW

NA
RO
NA
NA

RW

RO
RO

RW

NA

NA
NA
NA
NA
NA
NA
NA

NA

RO
RO
NA

NA
NA

RO
RO
RO
RO
NA
RO
RO
NA
RO

RO
RO
NA

NA
NA

RO
RO
RO
RO
NA
RO
RO
NA
RO

91

DataPort, DataLink, BAClink Object Definition (cont)

SCN TABLE

NAME

FA NS
Fan 1 Relay
Fan 2 Relay
Cooler/Pump Heater

DESCRIPTION STATUS UNITS POINT DataPort DataLink BAClink

Off/On
Off/On
Off/On

FAN _1
FAN _2

COOL_HTR

RO
RO
RO

RO
RO
RO

UNIT ANALOG VALUES
Cooler Entering Fluid
Cooler Leaving Fluid
Lead/Lag Fluid

snnn.n
snnn.n
snnn.n

°F (°C)
°F (°C)
°F (°C)

COOL_EWT

COOL_LWT

DUAL_LWT

RO
RO
RO

RO
RO
RO

TEMPERTURE RESET

OPTIONS

4-20 mA Reset Signal
Outside Air Temperature
Space Temperature

DEMAND LIMIT
4-20 mA Demand Signal
Demand Limit Switch 1
Demand Limit Switch 2
SCN Loadshed Signal

MISCELLANEOUS
Heat Request
Dual Setpoint Switch
Cooler LWT Setpoint
Ice Done

nn.n
snnn.n
snnn.n

nn.n
Off/On
Off/On

0, 1, 2

Off/On
Off/On
snnn.n
Off/On

ma

°F (°C)
°F (°C)

ma

°F (°C)

RST_MA

OAT
SPT

LMT_MA
DMD_SW1
DMD_SW2

DL_STAT

HEAT_REQ

DUAL_IN

LWT _SP

ICE_DONE

RO
RO
RO

RO
RO
RO
RO

RO
RO
RO
RO

RO
RW
RW

RO

RO

RO

RO

RO

RO

RO

RO

COOLING
Cooling Setpoint 1
Cooling Setpoint 2
Ice Setpoint

SETPOINT

RAMP LOADING
Cooling Ramp Loading

Brine Freeze Point
Timed Override Hours

Period 1 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 2 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 3 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 4 DOW (MTWTFSSH)
Occupied Time

OCCPC01S

Unoccupied Time
Period 5 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 6 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 7 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time
Period 8 DOW (MTWTFSSH)
Occupied Time
Unoccupied Time

LEGEND NOTE: In order to write to any point with DataLink or BAClink con-

Not Available

NA —

Read Only

RO —

Read/Write

RW —

–20 to 70 (–28.8 to 21.1)
–20 to 70 (–28.8 to 21.1)

–20 to 32 (–28.8 to 0.0)

0.2 to 2.0 (0.1 to 1.1)

–20 to 34 (–28.8 to 1.1)

0

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

00000000

00:00
00:00

°F (°C)
°F (°C)
°F (°C)

dF (dC)

°F (°C)

Hours OVR-EXT

trols, the machine must be configured for SCN control. CTRL

Control Method

CSP1
CSP2
CSP3

CRAMP

BRN_FRZ

DOW1

OCCTOD1

UNOCTOD1

DOW2

OCCTOD2

UNOCTOD2

DOW3

OCCTOD3

UNOCTOD3

DOW4

OCCTOD4

UNOCTOD4

DOW5

OCCTOD5

UNOCTOD5

DOW6

OCCTOD6

UNOCTOD6

DOW7

OCCTOD7

UNOCTOD7

DOW8

OCCTOD8

UNOCTOD8

NA
NA
NA

NA

NA
NA

NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA

RW
RW
RW

RW

RW
RW

RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW

(Configuration mode, sub-mode OPT2) must be set

to 3 = SCN Control.

RO
RO
NA

RO
RO
NA

RO
NA
NA

RO
NA
NA
RO

NA
NA
NA
NA

RW

NA
NA

NA

NA

RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW

Copyright 2003 Sterling

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 2
Ta b 5 c

PC 903 Catalog No. 533-00047 Printed in U.S.A. Form 30RA-2T Pg 92 1-03 Replaces: 30RA-1T

START-UP CHECKLIST FOR 30RA LIQUID CHILLER

(Remove and use for Job File)

I. Project Information

JOB NAME ______________________________________________________________________________

ADDRESS _______________________________________________________________________________

CITY ____________________________________________ STATE _______________ ZIP______________

INSTALLING CONTRACTOR ________________________________________________________________

SALES OFFICE ___________________________________________________________________________

START-UP PERFORMED BY ________________________________________________________________

Design Information

CAPACITY CEAT EWT LWT FLUID TYPE FLOW RATE P.D.

UNIT MODEL ______________________________ SERIAL ________________________________

II. Preliminary Equipment Check

IS THERE ANY PHYSICAL DAMAGE?



YES



NO

DESCRIPTION ____________________________________________________________________________

________________________________________________________________________________________

1. UNIT IS INSTALLED LEVEL AS PER THE INSTALLATION INSTRUCTIONS.

2. POWER SUPPLY AGREES WITH THE UNIT NAMEPLATE.

3. ELECTRICAL POWER WIRING IS INSTALLED PROPERLY.

4. UNIT IS PROPERLY GROUNDED.

5. ELECTRICAL CIRCUIT PROTECTION HAS BEEN SIZED AND INSTALLED PROPERLY.

6. ALL TERMINALS ARE TIGHT.

7. ALL PLUG ASSEMBLIES ARE TIGHT.

8. ALL CABLES AND THERMISTORS HAVE BEEN INSPECTED FOR CROSSED WIRES.

9. ALL THERMISTORS ARE FULLY INSERTED INTO WELLS.



















YES

YES

YES

YES

YES

YES

YES

YES

YES



















NO

NO

NO

NO

NO

NO

NO

NO

NO

Chilled Water System Check

1. ALL CHILLED WATER VALVES ARE OPEN.

2. ALL PIPING IS CONNECTED PROPERLY.





YES

YES





NO

NO

3. ALL AIR HAS BEEN PURGED FROM THE SYSTEM.

4. CHILLED WATER PUMP IS OPERATING WITH THE CORRECT ROTATION.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 2
Ta b 5 c

PC 903 Catalog No. 533-00047 Printed in U.S.A. Form 30RA-2T Pg CL-1 1-03 Replaces: 30RA-1T





YES

YES





NO

NO

5. CHILLED WATER PUMP STARTER INTERLOCKED WITH CHILLER.



YES



NO

6. CHILLED WATER FLOW SWITCH IS OPERATIONAL.

7. WATER LOOP VOLUME GREATER THAN MINIMUM REQUIREMENTS. (See Table 40).

8. PROPER LOOP FREEZE PROTECTION PROVIDED TO _____ °F (°C).
ANTIFREEZE TYPE _____________________ CONCENTRATION __________%.
IF OUTDOOR AMBIENT IS BELOW 32 F (0° C) THEN ITEMS 9-11 HAVE TO BE
COMPLETED TO PROVIDE COOLER FREEZE PROTECTION TO –20 F (–29 C). (REFER
TO WINTER SHUTDOWN FOR PROPER COOLER WINTERIZATION PROCEDURE.)

9. OUTDOOR PIPING WRAPPED WITH ELECTRIC HEATER TAPE,
INSULATED AND OPERATIONAL.

10. COOLER HEATERS INSTALLED AND OPERATIONAL.

11. CHILLED WATER PUMP CONTROLLED BY CHILLER.

III. Unit Start-Up

1. COMPRESSOR OIL LEVEL IS CORRECT.

2. VERIFY COMPRESSOR MOUNTING BOLT TORQUE IS 10-14 FT-LB. (13.5-18.9 N-M).

3. LEAK CHECK UNIT. LOCATE, REPAIR AND REPORT ANY REFRIGERANT LEAKS.

4. VOLTAGE IS WITHIN UNIT NAMEPLATE RANGE.





















YES

YES

YES

YES

YES

YES

YES

YES

YES

YES





















NO

NO

NO

NO

NO

NO

NO

NO

NO

NO

5. CONTROL TRANSFORMER PRIMARY CONNECTION SET FOR PROPER VOLTAGE.

6. CONTROL TRANSFORMER SECONDARY VOLTAGE =

7. CHECK VOLTAGE IMBALANCE: A-B A-C B-C

AVERAGE VOLTAGE = (A-B + A-C + B-C)/3
MAXIMUM DEVIATION FROM AVERAGE VOLTAGE =
VOLTAGE IMBALANCE = ____________% (MAX. DEVIATION/AVERAGE VOLTAGE) X 100
VOLTAGE IMBALANCE LESS THAN 2%.
(DO NOT START CHILLER IF VOLTAGE IMBALANCE IS GREATER THAN 2%.
CONTACT LOCAL UTILITY FOR ASSISTANCE.)

8. VERIFY COOLER FLOW RATE.

PRESSURE ENTERING COOLER ________ psig (kPa)
PRESSURE LEAVING COOLER ________ psig (kPa)
COOLER PRESSURE DROP ________ psig (kPa)
Psig X 2.31 ft./psi = ________ ft of water
kPa X 0.334 m/psi ________ m of water
COOLER FLOW RATE ________ gpm (l/s) (See Cooler Pressure

Drop Curves from
Installation, Start-up and
Service Instructions)

Start and Operate Machine. Complete the Following:

1. COMPLETE COMPONENT TEST.









YES

YES

YES

YES









NO

NO

NO

NO

2. CHECK REFRIGERANT AND OIL CHARGE.

3. RECORD COMPRESSOR MOTOR CURRENT.

4. RECORD CONFIGURATION SETTINGS.

5. RECORD OPERATING TEMPERATURES AND PRESSURES.









YES

YES

YES









NO

NO

NO

NO

YES

6. PROVIDE OPERATING INSTRUCTIONS TO OWNER’S PERSONNEL. Instruction Time ________ hours.

CL-2

OPERATING DATA:

RECORD THE FOLLOWING INFORMATION FROM THE PRESSURES AND TEMPERATURES MODES WHEN
MACHINE IS IN A STABLE OPERATING CONDITION:

PRESSURE/TEMPERATURE

CIRCUIT A CIRCUIT B

DISCHARGE PRESSURE DP.A DP.B

SUCTION PRESSURE SP.A SP.B

SATURATED CONDENSING TEMP SCT.A SCT.B

SATURATED SUCTION TEMP SST.A SST.B

LIQUID LINE TEMPERATURE*

DISCHARGE LINE TEMPERATURE*

RETURN GAS TEMPERATURE*

*Readings taken with a digital thermometer.

COOLER EWT EWT

COOLER LWT LWT

OUTDOOR-AIR TEMPERATURE OAT

CONTROL POINT CTPT

PERCENT TOTAL CAPACITY CAP

LEAD/LAG LEAVING FLUID DLWT (Dual Chiller Control Only)

Compressor Running Current —

All readings taken at full load.

COMPRESSOR MOTOR CURRENT L1 L2 L3

COMPRESSOR A1

COMPRESSOR A2

COMPRESSOR B1

COMPRESSOR B2

CONDENSER FAN MOTOR CURRENT L1 L2 L3

FAN MOTOR 1

FAN MOTOR 2

FAN MOTOR 3

FAN MOTOR 4

COOLER PUMP MOTOR CURRENT L1 L2 L3

COOLER PUMP 1

COOLER PUMP 2

CL-3

Record Software Versions
MODE — RUN STATUS

SUB-MODE ITEM DISPLAY ITEM

VERS MBB CESR-131279- _ _-_ _

MARQ CESR-131171- _ _-_ _
EMM CESR-131174- _ _-_ _
NAVI CESR-131227- _ _-_ _

(PRESS ENTER & ESCAPE SIMULTANEOUSLY TO OBTAIN
SOFTWARE VERSIONS)

COMMENTS:

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

EXPANSION

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

SIGNATURES:

START-UP CUSTOMER
TECHNICIAN _____________________________ REPRESENTATIVE _____________________________

DATE ___________________________________ DATE ________________________________________

CL-4

III. Unit Start-Up (cont)

RECORD CONFIGURATION SETTINGS

UNIT (Configuration Settings)

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

UNIT UNIT CONFIGURATION

SZA.1 XX COMPRESSOR A1 SIZE
SZA.2 XX COMPRESSOR A2 SIZE
SZB.1 XX COMPRESSOR B1 SIZE
SZB.2 XX COMPRESSOR B2 SIZE

SH.SP XX.X ∆F SUPERHEAT SETPOINT

REFG X REFRIGERANT
FAN .S X FAN S TAG I N G SELECT

PRESS ESCAPE KEY TO DISPLAY ‘UNIT’. PRESS DOWN ARROW KEY TO DISPLAY ‘OPT1’.
PRESS ENTER KEY. RECORD CONFIGURATION INFORMATION BELOW:

OPTIONS1 (Options Configuration)

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

OPT1 UNIT OPTIONS 1 HARDWARE

FLUD X COOLER FLUID

MLV.S YES/NO MINIMUM LOAD VALVE SELECT
MMR.S YES/NO MOTORMASTER SELECT
RG.EN ENBL/DSBL RETURN GAS SENSOR ENABLE

CPC ON/OFF COOLER PUMP CONTROL
PM1E YES/NO COOLER PUMP 1 ENABLE
PM2E YES/NO COOLER PUMP 2 ENABLE

PM.P.S YES/NO COOLER PMP PERIODIC STRT

PM.SL X COOLER PUMP SELECT
PM.DY XX MIN COOLER PUMP SHUTDOWN DLY

PM.DT XXXX HRS PUMP CHANGEOVER HOURS

ROT.P YES/NO ROTATE COOLER PUMPS NOW

EMM YES/NO EMM MODULE INSTALLED

CL-5

III. Unit Start-Up (cont)

PRESS ESCAPE KEY TO DISPLAY ‘OPT1’. PRESS DOWN ARROW KEY TO DISPLAY ‘OPT2’.
PRESS ENTER KEY.

RECORD CONFIGURATION INFORMATION BELOW.

OPTIONS2 (Options Configuration)

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

OPT2 UNIT OPTIONS 2 CONTROLS

CTRL X CONTROL METHOD

SCNA XXX SCN ADDRESS
SCNB XXX SCN BUS NUMBER

BAUD X SCN BAUD RATE
LOAD X LOADING SEQUENCE SELECT

LLCS X LEAD/LAG CIRCUIT SELECT

LCWT XX.X ∆F HIGH LCW ALERT LIMIT

DELY XX MINUTES OFF TIME
ICE.M ENBL/DSBL ICE MODE ENABLE
CLS.C ENBL/DSBL CLOSE CONTROL SELECT

LS.MD X LOW SOUND MODE SELECT

LS.ST 00:00 LOW SOUND START TIME
LS.ND 00:00 LOW SOUND END TIME

LS.LT XXX % LOW SOUND CAPACITY LIMIT

RSET (Reset Configuration Settings)

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

RSET RESET COOL TEMP

CRST X COOLING RESET TYPE

MA.DG XX.X °F 4-20 - DEGREES RESET
RM.NO XXX.X °F REMOTE - NO RESET TEMP

RM.F XXX.X °F REMOTE - FULL RESET TEMP

RM.DG XX.X °F REMOTE - DEGREES RESET

RT.NO XXX.X °F RETURN - NO RESET TEMP

RT.F XXX.X °F RETURN - FULL RESET TEMP
RT.DG XX.X °F RETURN - DEGREES RESET
DMDC X DEMAND LIMIT SELECT

DM20 XXX % DEMAND LIMIT AT 20 MA

SHNM XXX LOADSHED GROUP NUMBER

SHDL XXX % LOADSHED DEMAND DELTA
SHTM XXX MAXIMUM LOADSHED TIME

DLS1 XXX % DEMAND LIMIT SWITCH 1
DLS2 XXX % DEMAND LIMIT SWITCH 2
LLEN ENBL/DSBL LEAD/LAG CHILLER ENABLE

MSSL SLVE/MAST MASTER/SLAVE SELECT

SLVA XXX SLAVE ADDRESS

LLBL X LEAD/LAG BALANCE SELECT
LLBD XXX LEAD/LAG BALANCE DELTA
LLDY XXX LAG START DELAY

PARA YES/NO PARALLEL CONFIGURATION

CL-6

III. Unit Start-Up (cont)

PRESS ESCAPE KEY TO DISPLAY ‘RSET’. PRESS DOWN ARROW KEY TO DISPLAY ‘SLCT’.
PRESS ENTER KEY.

RECORD CONFIGURATION INFORMATION BELOW:

SLCT (Setpoint and Ramp Load Configuration)

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

SLCT SETPOINT AND RAMP LOAD

CLSP X COOLING SETPOINT SELECT

RL.S ENBL/DSBL RAMP LOAD SELECT
CRMP X.X COOLING RAMP LOADING
SCHD XX SCHEDULE NUMBER

Z.GN X.X DEADBAND MULTIPLIER

PRESS ESCAPE KEY SEVERAL TIMES TO GET TO THE MODE LEVEL (BLANK DISPLAY). USE THE
ARROW KEYS TO SCROLL TO THE SET POINT LED. PRESS ENTER TO DISPLAY SETPOINTS.
RECORD CONFIGURATION INFORMATION BELOW:

SETPOINT

SUBMODE ITEM DISPLAY DESCRIPTION VALUE

COOL COOLING SETPOINTS

CSP.1 XXX.X °F COOLING SETPOINT 1
CSP.2 XXX.X °F COOLING SETPOINT 2
CSP.3 XXX.X °F ICE SETPOINT

HEAD PRESSURE SETPOINTS

HEAD

FRZ

HD.P.A XXX.X °F CALCULATED HP SETPOINT A
HD.P.B XXX.X °F CALCULATED HP SETPOINT B

BRINE FREEZE SETPOINT

BR.FZ XXX.X °F BRINE FREEZE POINT

CL-7

III. Unit Start-Up (cont)

COMPONENT TEST

USE ESCAPE/ARROW KEYS TO ILLUMINATE CONFIGURATION LED. PRESS ENTER TO DISPLAY ‘DISP’.
PRESS ENTER AGAIN TO DISPLAY ‘TEST’ FOLLOWED BY ‘OFF’. PRESS ENTER TO STOP DISPLAY AT
‘OFF’ AND ENTER AGAIN SO ‘OFF’ DISPLAY FLASHES. ‘PA S S ’ AND ‘WORD’ WILL FLASH IF PASSWORD
NEEDS TO BE ENTERED. PRESS ENTER TO DISPLAY PASSWORD FIELD AND USE THE ENTER KEY FOR
EACH OF THE FOUR PASSWORD DIGITS. USE ARROW KEYS IF PASSWORD IS OTHER THAN STANDARD.
AT FLASHING ‘OFF’ DISPLAY, PRESS THE UP ARROW KEY TO DISPLAY ‘ON’ AND PRESS ENTER. ALL LED
SEGMENTS AND MODE LEDS WILL LIGHT UP. PRESS ESCAPE TO STOP THE TEST. PRESS ESCAPE TO
RETURN TO THE ‘DISP’ DISPLAY. PRESS THE ESCAPE KEY AGAIN AND USE THE ARROW KEYS TO ILLU­MINATE THE SERVICE TEST LED. PRESS ENTER TO DISPLAY ‘TEST’. PRESS ENTER TO STOP DISPLAY
AT ‘OFF’ AND ENTER AGAIN SO ‘OFF’ FLASHES. PRESS THE UP ARROW KEY AND ENTER TO ENABLE
THE MANUAL MODE. PRESS ESCAPE AND DISPLAY NOW SAYS ‘TEST’ ‘ON’. REFER TO THE TABLE
BELOW.

Service Test Mode and Sub-Mode Directory

SUB-MODE

TEST

OUTS

CMPA

KEYPAD

ENTRY

ENTER

ENTER

ENTER

ITEM DISPLAY

ON/OFF SERVICE TEST MODE To Enable Service Test Mode,

OUTPUTS AND PUMPS

FAN1 ON/OFF FAN 1 RELAY

FAN2 ON/OFF FAN 2 RELAY

CLP.1 ON/OFF COOLER PUMP 1 RELAY

CLP.2 ON/OFF COOLER PUMP 2 RELAY

CL.HT ON/OFF COOLER/PUMP HEATER

RMT.A ON/OFF REMOTE ALARM RELAY

CIRCUIT A COMPRESSOR TEST

CC.A1 ON/OFF COMPRESSOR A1 RELAY

CC.A2 ON/OFF COMPRESSOR A2 RELAY

ITEM

EXPANSION

COMMENT

move Enable/Off/Remote
Contact switch to OFF. Change
TEST to ON. Move switch to
ENABLE.

SIZES 010-018,
Condenser fan at low speed
SIZES 022-030
Condenser fan A1 energized
SIZES 032-055,
Condenser fan A2 energized

SIZES 022-030,
Condenser fan A2 energized
SIZES 032-040,
Condenser fan B1 at high speed
SIZES 042-055,
Condenser fan B2 energized

Completed

(Yes/No)

MLV ON/OFF MINIMUM LOAD VALVE RELAY

CIRCUIT B COMPRESSOR TEST

ENTER

CMPB

NOTE: If the unit has a single circuit, the Circuit B items will not appear in the display, except the ability to configure circuit B will be displayed.

Copyright 2003 Sterling

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 2
Ta b 5 c

PC 903 Catalog No. 533-00047 Printed in U.S.A. Form 30RA-2T Pg CL-8 1-03 Replaces: 30RA-1T

CC.B1 ON/OFF COMPRESSOR B1 RELAY See Note

CC.B2 ON/OFF COMPRESSOR B2 RELAY See Note

MLV ON/OFF MINIMUM LOAD VALVE RELAY See Note

CUT ALONG DOTTED LINE CUT ALONG DOTTED LINE

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - -