Operating & Maintenance Manual
Group: Chiller
Part Number: 10000199900
Date: Sept 2010
Supercedes: July 2010
OM 1051-2
Pathfinder™ Air-Cooled Chillers
AWS 150A through AWS 530A (Includes Optional Compressor VFD Models)
50/60 Hertz,
R-134a
Software Version: 2507500205
© 2010 McQuay International
Table of Contents
INTRODUCTION ........................................................3
OPERATING LIMITS: ...............................................4
E
CONOMIZER CONTROL
L
IQUID INJECTION
L
IQUID LINE SOLENOID VALVE
C
APACITY OVERRIDES – LIMITS OF OPERATION
........................................... 42
.................................................... 42
............................... 43
...... 43
CONTROLLER FEATURES .....................................4
GENERAL DESCRIPTION........................................5
C
ONTROL PANEL LAYOUT
P
OWER PANEL LAYOUT
E
CONOMIZER COMPONENTS
CONTROLLER DESCRIPTION ...............................9
H
ARDWARE STRUCTURE
S
YSTEM ARCHITECTURE
SEQUENCE OF OPERATION ................................11
CONTROLLER OPERATION.................................15
S
ETPOINTS
UNIT FUNCTIONS....................................................22
C
ALCULATIONS
U
NIT AVAILABILITY
U
NIT MODE SELECTION
U
NIT CONTROL STATES
U
NIT STATUS
I
CE MODE START DELAY
E
VAPORATOR PUMP CONTROL
N
OISE REDUCTION
L
EAVING WATER TEMPERATURE
U
NIT CAPACITY CONTROL
U
NIT CAPACITY OVERRIDES
CIRCUIT FUNCTIONS ............................................34
................................................................18
.........................................................22
............................................................24
....................................................25
..........................................5
..............................................6
.......................................7
.............................................9
...........................................10
.................................................22
............................................23
............................................23
..........................................24
.................................25
(LWT) R
........................................28
.....................................30
ESET
.......26
ALARMS AND EVENTS ......................................... 44
S
IGNALING ALARMS
C
LEARING ALARMS/FAULTS
D
ESCRIPTION OF ALARMS
A
LARM LISTING
U
NIT FAULTS
U
NIT WARNINGS
C
IRCUIT FAULTS
C
IRCUIT PROBLEMS
A
LARM LOGGING
E
VENT LOG
.............................................................. 55
................................................ 44
.................................... 44
........................................ 45
....................................................... 45
........................................................... 47
...................................................... 48
...................................................... 49
................................................. 54
..................................................... 55
USING THE CONTROLLER.................................. 56
N
AVIGATING
OPTIONAL REMOTE USER INTERFACE ......... 61
............................................................ 57
OPTIONAL COMPRESSOR VFD.......................... 63
F
AULTS AND MINOR FAULTS/ALARMS
C
LEARING
N
AVIGATING
OPTIONAL POWER FACTOR CORRECTION
CAPACITORS........................................................... 67
START-UP AND SHUTDOWN ............................... 68
T
EMPORARY SHUTDOWN
E
XTENDED (SEASONAL) SHUTDOWN
FIELD WIRING DIAGRAM ................................... 71
VFD F
VFD F
AULTS
.......................................... 63
AULT CODES
......................................... 68
.................... 63
............................ 63
....................... 69
C
ALCULATIONS
C
IRCUIT CONTROL LOGIC
C
IRCUIT STATUS
C
OMPRESSOR CONTROL
C
ONDENSER FAN CONTROL
F
AN CONTROL WITHOUT
F
AN CONTROL WITH
EXV C
ONTROL
.........................................................34
.........................................35
.......................................................36
............................................37
......................................38
VFD ..................................38
VFD.........................................40
.........................................................40
Modbus
Manufactured in an ISO Certified Facility
SYSTEM MAINTENANCE ..................................... 73
P
REVENTATIVE MAINTENANCE SCHEDULE
APPENDIX ................................................................ 78
D
EFINITIONS
............................................................ 78
.............. 77
Unit controllers are LONM
optional LONW
ORKS
ARK
certified with an
communications module
2010 McQuay International. Information covers the McQuay International products at the time of publication and we reserve the right to make
changes in design and construction at anytime without notice. The following are trademarks or registered trademarks of their respective
companies: BACnet from ASHRAE; LONM
from McQuay International; Excel from Microsoft Corp.
2 OM 1051-2
ARK and LONWORKS
from Echelon Corporation; McQuay, MicroTech III, Guardister, and Open Choice
Introduction
This manual provides setup, operating, troubleshooting and maintenance information for the
Daiken McQuay Pathfinder chillers.
Dangers indicate a hazardous situation which will result in death or serious injury if not avoided.
Warnings indicate potentially hazardous situations, which can result in property damage, severe
Cautions indicate potentially hazardous situations, which can result in personal injury or equipment
Software Version:
The unit software and BSP (Board Support Package) versions can be viewed using the
keypad/display. From the Main Menu, turn the knob to the right until you reach the About Chiller
menu and press Enter (the knob). The software version is displayed as "App Version =". Scroll
down in this menu (turn knob to the right), the BSP version will also be displayed ("BSP
Version=").
H
AZARD IDENTIFICATION INFORMATION
!
DANGER
!
WARNING
personal injury, or death if not avoided.
!
CAUTION
damage if not avoided.
• App Version 2507500205 for units with or without the optional compressor VFDs
!
WARNING
Electric shock hazard: can cause personal injury or equipment damage. This equipment must
be properly grounded. Connections to, and service of, the MicroTech III control panel must be
performed only by personnel who are knowledgeable in the operation of this equipment .
!
CAUTION
Static sensitive components. A static discharge while handling electronic circuit boards can
cause damage to the components. Discharge any static electrical charge by touching the bare
metal inside the control panel before performing any service work. Never unplug any cables,
circuit board terminal blocks, or power plugs while power is applied to the panel.
NOTICE
This equipment generates, uses, and can radiate radio frequency energy and, if not
installed and used in accordance with this instruction manual, can cause interference to
radio communications. Operation of this equipment in a residential area can cause
harmful interference, in which case the user will be required to correct the interference at
the user’s own expense. McQuay International Corporation disclaims any liability
resulting from any interference or for the correction thereof.
OM 1051-2 3
Operating Limits:
• Maximum standby ambient temperature, 130°F (55°C)
• Maximum operating ambient temperature is 115°F (46°C), or 125°F (52°C) with the addition
of the optional high ambient package
• Minimum operating ambient temperature (standard), 35°F (2°C)
• Minimum operating ambient temperature (with optional low-ambient control), 0°F (-18°C)
• Leaving chilled water temperature, 39.2°F to 59.0°F (4.0°C to 15.0°C)
• Leaving chilled fluid temperatures with glycol, 24.8°F to 59.0°F (-4.0°C to 15.0°C). Normal
unloading.
• Leaving temperature in ICE mode, 17.6°F to 39.2°F (-8.0°C to 4°C). No unloading.
• Operating Delta-T range, 6°F to 16°F (3.3°C to 8.9°C)
• Maximum operating inlet fluid temperature, 76°F (24°C)
• Maximum non-operating inlet fluid temperature, 100°F (38°C)
Controller Features
Readout of the following temperature and pressure readings:
• Entering and leaving chilled water temperature
• Saturated evaporator refrigerant temperature and pressure
• Saturated condenser temperature and pressure
• Outside air temperature
• Suction and discharge line temperatures − calculated superheat for discharge and suction
lines
• Oil pressure
Automatic control of primary and standby chilled water pumps. The control will start one of the
pumps (based on lowest run-hours) when the unit is enabled to run (not necessarily running on a
call for cooling) and when the water temperature reaches a point of freeze possibility.
Two levels of security protection against unauthorized changing of setpoints and other control
parameters.
Warning and fault diagnostics to inform operators of warning and fault conditions in plain
language. All events and alarms are time and date-stamped for identification of when the fault
condition occurred.
Twenty-five previous alarms are available.
Remote input signals for chilled water reset, demand limiting, and unit enable.
Test mode allows the service technician to manually control the controllers’ outputs and can be
useful for system checkout.
Building Automation System (BAS) communication capability via LonTalk, Modbus, or
BACnet standard protocols for all BAS manufacturers-simplified with McQuay’s Open
Choices feature.
Pressure transducers for direct reading of system pressures. Preemptive control of low evaporator
pressure conditions and high discharge temperature and pressure to take corrective action prior to
a fault trip.
4 OM 1051-2
General Description
Switch
Switch
The control panel is located on the front of the unit at the compressor end. There are three doors. The
control panel is behind to left-hand door. The power panel is behind the middle and right-hand doors.
General Description
The MicroTech III control system consists of a microprocessor-based controller and a number of extension
modules, which vary depending on the unit size and conformation. The control system provides the
monitoring and control functions required for the controlled, efficient operation of the chiller.
The operator can monitor all critical operating conditions by using the screen located on the main controller.
In addition to providing all normal operating controls, the MicroTech III control system will take corrective
action if the chiller is operating outside of its normal design conditions. If a fault condition develops, the
controller will shut a compressor, or the entire unit, down and activate an alarm output.
The system is password protected and only allows access by authorized personnel. Except that some basic
information is viewable and alarms can be cleared without a password. No settings can be changed.
Additional information about the Daikin McQuay Pathfinder Chiller is available in Catalog 600 and IM
997, which can be found on www.mcquay.com.
Control Panel Layout
Figure 1, Control Panel Components, Three-Circuit Unit, w/o VFD
Controller
Fuse
Emergency
Switch
Relay
Control
Circuit
Breaker
Unit On/Off
Circuit #1
Pumpdown
Circuit #2
Pumpdown
Switch
Circuit #3
Pumpdown
Switch
Alarm & Limit
Extension
Module
MicroTech III
Main
Controller
Fan Control
Extension
Modules
Emergency
Switch
Located on
Front Door
OM 1051-2 5
NOTES:
Fan
Circuit Breaker
s
1 per Fan
,
Circuit #
1
Circuit Breaker
Circuit Breaker
1. The Emergency Switch Relay de-energizes all circuit’s control power when activated, causing an
immediate compressor and fan shutdown. The red emergency button switch is located on the
front of the control panel door.
2. The control power transformer is located in the power panel adjacent to the control panel.
3. Additional extension (aka expansion) modules are located elsewhere on the chiller.
4. See the VFD section for a description of the panel used with the VFD option as it is considerably
different from the standard panel.
Power Panel Layout
The power panel is at the front of the unit, behind the two doors to the right.
Figure 2, Power Panel, Three-Circuit Units, w/o VFD
Fan Contactors
Fan Contactors
1 per Fan, Circuit #2
Fan Contactors
1 per Fan, Circuit #3
Compressor #1
Circuit Breaker
Single Point
Disconnect Switch with
Compressor #3
Compressor #2
6 OM 1051-2
Line/120V
Transformer
Incoming Power
Connections
NOTE: See the VFD section of this manual for a description of the power used with the VFD option
as it is considerably different from the standard panel.
Economizer Components
The chiller may or may not have economizers depending on design capacity
requirements. An economizer is a well-proven device to increase a refrigerant circuit’s
capacity and efficiency.
Figure 3, Economizer Components
Brazed-plate
Heat Exchanger
Gas to Comp.
Interstage
Liquid from
Condenser
TXV LLSV
Warm liquid from the condenser is fed into the economizer where it is cooled by flashing off
liquid also from the condenser. The flash gas is piped to a compressor interstage point.
Lowering the liquid refrigerant temperature to the evaporator decreases its enthalpy (heat
content) and results in a greater amount of heat absorption from the chilled water.
OM 1051-2 7
Liquid Feed
to
Economizer
Liquid Feed
to
Evaporator
Figure 4, Piping Schematic with Economizer Circuit, One Circuit Shown
Figure 5, Piping Schematic without Economizer Circuit, One Circuit Shown
8 OM 1051-2
Controller Description
Hardware Structure
The MicroTech III control system for Pathfinder chillers consists of a main unit controller with a
number of extension input/output I/O modules attached depending on the chiller size and
configuration.
One of the optional BAS communication modules may be included.
An optional Remote Operator Interface panel may be included, connected with up to nine
Pathfinder units.
The MicroTech III controllers used on Pathfinder chillers are not interchangeable with previous
MicroTech II controllers.
MicroTech III unit controller
Remote Operator Interface
BACnet/
MSTP
Communication
MODbus LON
BACnet/IP
Extension I/O Modules
OM 1051-2 9
System Architecture
The overall controls architecture uses the following:
• One MicroTech III main controller
• I/O extension modules (sometimes referred to as “controllers”) as needed depending
on the configuration of the unit
• Optional BAS interface as selected
Figure 6, System Architecture
BAS Interface
(BACnet, Lon,
Modbus)
MicroTech III Main Controller
Peripheral Bus
I/O Extension
Alarm/Limiting
I/O Extension
Compressor 1
I/O Extension
Compressor 2
I/O Extension
Compressor 3
I/O Extension
Fans Circuit 1
and 2
I/O Extension
EXV 1
I/O Extension
EXV 2
I/O Extension
EXV 3
I/O Extension
Fans Circuit 3
I/O Extension
Fans Circuit 3
and 4
I/O Extension
Fans Circuit 4
I/O Extension
Compressor 4
I/O Extension
EXV 4
10 OM 1051-2
Sequence of Operation
Figure 7, Unit Sequence of Operation (see Figure 9 for circuit sequence of operation)
Unit power up
Unit in Off state
Is unit enabled?
Yes
Is low ambient lockout
active?
No
Evaporator pump output on
AWS Chiller Sequence of Operation in Cool Mode
The chiller may be disabled via the unit switch, the remote switch, the keypad
enable setting, or the BAS network. In addition, the chiller will be disabled if all
No
circuits are disabled, or if there is a unit alarm. If the chiller is disabled, the unit
status display will reflect this and also show why it is disabled.
If the unit switch is off, the unit status will be Off:Unit Switch. If the chiller is
disabled due to network command, the unit status will be Off:BAS Disable. When
Yes
the remote switch is open, the unit status will be Off:Remote Switch. When a unit
alarm is active, the unit status will be Off:Unit Alarm. In cases where no circuits
are enabled, the unit status will be Off:All Cir Disabled. If the unit is disabled via
the Chiller Enable set point, the unit status will be Off:Keypad Disable.
Low ambient lockout will prevent the chiller from starting even if it is otherwise
enabled. When this lockout is active, the unit status will be Off:Low OAT Lock.
If the chiller is enabled, then the unit will be in the Auto state and the evaporator
water pump output will be activated.
No
Is flow present?
Yes
Wait for chilled water loop to
recirculate.
Keep pump output on while
chiller is enabled and either
running or ready to run.
Is there enough load to
start chiller?
Yes
The chiller will then wait for the flow switch to close, during which time the unit
status will be Auto:Wait for flow.
After establishing flow, the chiller will wait some time to allow the chilled water loop
to recirculate for an accurate reading of the leaving water temperature. The unit
status during this time is Auto:Evap Recirc.
No
The chiller is now ready to start if enough load is present. If the LWT is not higher
than the Active Setpoint plus the Start Up Delta T, the unit status will be Auto:Wait
for load.
If the LWT is higher than the Active Setpoint plus the Start Up Delta T, the unit
status will be Auto. A circuit can start at this time.
OM 1051-2 11
12 OM 1051-2
OM 1051-2 13
Figure 8, Circuit Sequence of Operation
Unit power up
Circuit is in Off state
Is circuit is enabled to
start?
Yes
Are compressor cycle
timers active?
No
Is compressor oil sump
ready?
No
AWS Sequence of Operation - Circuits
When the circuit is in the Off state the EXV is closed, compressor is off, and all fans
are off.
The circuit must be enabled before it can run. It may be disabled for several
reasons. When the circuit switch is off, the status will be Off:Circuit Switch.
If the BAS has disabled the circuit, the status will be Off:BAS Disable. If the circuit
Yes
has an active stop alarm then the status will be Off:Cir Alarm. If the circuit has
been disabled via the circuit mode set point, the status will be Off:Cir Mode
Disable.
No
A minimum time must pass between the previous start and stop of a compressor
and the next start. If this time has not passed, a cycle timer will be active and the
circuit status will be Off:Cycle Timer.
If the compressor is not ready due to refrigerant in the oil, the circuit cannot start.
The circuit status will be Off:Refr In Oil.
Yes
Circuit is ready to start
Is circuit commanded to
start?
Yes
Run circuit
Is circuit commanded to
shut down?
Yes
Pumpdown circuit
No
No
If the compressor is ready to start when needed, the circuit status will be
Off:Ready.
When the circuit begins to run, the compressor will be started and the EXV, fans,
and other devices will be controlled as needed. The normal circuit status at this
time will be Run.
When the circuit is commanded to shut down, a normal shut down of the circuit will
be performed. The circuit status during this time will be Run:Pumpdown. After
the shut down is completed, the circuit status will normally be Off:Cycle Timer
initially.
14 OM 1051-2
Controller Operation
MicroTech III Inputs/Outputs
I/O for the unit control and for circuits one and two are found on CP1.
The chiller may be equipped with two or three compressors.
Analog Inputs
# Description Signal Source Expected Range
AI1 Evaporator Entering Water Temp NTC Thermister (10K@25°C) -50°C – 120°C
AI2 Evaporator Leaving Water Temp NTC Thermister (10K@25°C) -50°C – 120°C
AI3 Evaporator #1 Leaving Water Temp (*) NTC Thermister (10K@25°C) -50°C – 120°C
X1 Evaporator #2 Leaving Water Temp (*) NTC Thermister (10K@25°C) -50°C – 120°C
X2 Outside Ambient Temperature NTC Thermister (10K@25°C) -50°C – 120°C
X4 LWT Reset 4-20 mA Current 1 to 23 mA
*Evaporator #1 LWT and Evaporator #2 LWT will only be used when unit is configured with
four circuits
Analog Outputs
# Description Output Signal Range
X5 Fan VFD #1 0-10VDC 0 to 100% (1000 steps resolution)
X6 Fan VFD #2 0-10VDC 0 to 100% (1000 steps resolution)
X7 Fan VFD #3 0-10VDC 0 to 100% (1000 steps resolution)
X8 Fan VFD #4 0-10VDC 0 to 100% (1000 steps resolution)
Digital Inputs
# Description Signal Off Signal On
DI1 Unit PVM Fault No Fault
DI2 Evaporator Flow Switch No Flow Flow
DI3 Double Setpoint/ Mode Switch Cool mode Ice mode
DI4 Remote Switch Remote off Remote on
DI5 Unit Switch Unit off Unit on
DI6 Emergency Stop Unit off/rapid stop Unit on
Digital Outputs
# Description Output OFF Output ON
DO1 Evaporator Water Pump Pump Off Pump On
Alarm Active
DO2 Unit Alarm Alarm not Active
DO3 Circuit #1 Fan Step #1 Fan Off Fan On
DO4 Circuit #1 Fan Step #2 Fan Off Fan On
DO5 Circuit #1 Fan Step #3 Fan Off Fan On
DO6 Circuit #1 Fan Step #4 Fan Off Fan On
DO7 Circuit #2 Fan Step #1 Fan Off Fan On
DO8 Circuit #2 Fan Step #2 Fan Off Fan On
DO9 Circuit #2 Fan Step #3 Fan Off Fan On
DO10 Circuit #2 Fan Step #4 Fan Off Fan On
(Flashing= circuit
alarm)
OM 1051-2 15
Expansion I/O Compressor #1 to #3
Analog Inputs
# Description Signal Source Expected Range
X1 Discharge Temperature NTC Thermister (10K@25°C) -50°C – 125°C
X2 Evaporator Pressure Ratiometric 0.5-4.5 Vdc -100 kPa to 700 kPa
X3 Oil Pressure Ratiometric 0.5-4.5 Vdc 0 kPa to 3000 kPa
X4 Condenser Pressure Ratiometric 0.5-4.5 Vdc 0 kPa to 3000 kPa
X7 Motor Temperature See note below
Note: European chillers will have the PTC thermistor in the compressor motor connected
to this input. X7 is configured as an NTC 10k input for European chillers.
Analog Outputs
# Description Output Signal Range
Not Needed
Digital Inputs
# Description Signal Off Signal On
X6 Starter Fault Fault No fault
X7 Motor Protection See note below
DI1 High Pressure Switch Fault No fault
Note: US chillers will use the motor protection board connected to this input. X7 is
configured as a digital input for US chillers.
Digital Outputs
Europe Configuration
# Description Output Off Output On
DO1 Start Compressor Compressor Off Compressor On
DO2 Economizer Solenoid Closed Solenoid Open
DO3 Non-modulating Slide Load/Unload Solenoid Closed Solenoid Open
DO4 Liquid Injection Solenoid Closed Solenoid Open
DO5 Modulating Slide Load Solenoid Closed Solenoid Open
DO6 Modulating Slide Unload Solenoid Closed Solenoid Open
X5 Modulating Slide “turbo” Solenoid Closed Solenoid Open
U.S. Configuration
# Description Output Off Output On
DO1 Start Compressor Compressor Off Compressor On
DO2 Economizer Solenoid Closed Solenoid Open
DO3 Non-modulating Slide Load Solenoid Closed Solenoid Open
DO4 Non-modulating Slide Unload Solenoid Closed Solenoid Open
DO5 Modulating Slide Load Solenoid Closed Solenoid Open
DO6 Modulating Slide Unload Solenoid Closed Solenoid Open
X5 Modulating Slide ‘Turbo’ Solenoid Closed Solenoid Open
X8 Liquid Injection Solenoid Closed Solenoid Open
16 OM 1051-2
I/O EXV Circuit #1 to #3
Analog Inputs
# Description Signal Source Expected Range
X2 Suction Temperature NTC Thermister 10K@25°C) -50°C – 120°C
X3 Slide Position LVDT 4 to 20 mA 0% to 100%
Analog Outputs
# Description Output Signal Range
Not Needed
Digital Inputs
# Description Signal Off Signal On
DI1 Low Pressure switch Fault No fault
Digital Outputs
# Description Output Off Output On
DO1 Liquid Line Solenoid Closed Solenoid Open
Stepper Motor Output
# Description
M1+
M1-
M2+
M2-
EXV Stepper Coil 1
EXV Stepper Coil 2
Extension I/O Fan Module Circuit #1 & 2
Digital Inputs
# Description Output Off Output On
DI1 PVM/GFP Circuit #1 Fault No fault
DI2 PVM/GFP Circuit #2 Fault No fault
Digital Outputs
# Description Output Off Output On
DO1 Circuit #1 Fan Step #5 Fan Off Fan On
DO2 Circuit #1 Fan Step #6 Fan Off Fan On
DO3 Circuit #2 Fan Step #5 Fan Off Fan On
DO4 Circuit #2 Fan Step #6 Fan Off Fan On
Extension I/O Fan Module Circuit #3
Digital Outputs
# Description Output Off Output On
DO1 Circuit #3 Fan Step #5 Fan Off Fan On
DO2 Circuit #3 Fan Step #6 Fan Off Fan On
Extension I/O Unit Alarm & Limiting
Analog Inputs
# Description Signal Source Range
X3 Demand Limit 4-20 mA 1 to 23 mA
X4 Unit Current 4-20 mA 1 to 23 mA
Analog Outputs
# Description Output Signal Range
Not Needed
OM 1051-2 17
Digital Inputs
# Description Signal Off Signal On
X1 External Alarm/Event
X2 Current Limit Enable No Limiting Limiting
X5 Circuit Switch #1 Circuit Off Circuit On
X6 Circuit Switch #2 Circuit Off Circuit On
X7 Circuit Switch #3 Circuit Off Circuit On
External Device
Failure
External Device OK
Digital Outputs
# Description Output Off Output On
DO1 Evaporator Water Pump #2 Pump Off Pump On
DO2 Open
DO3 Circuit #1 Alarm No Alarm Alarm
DO4 Circuit #2 Alarm No Alarm Alarm
DO5 Circuit #3 Alarm No Alarm Alarm
Setpoints
The following parameters are remembered during power off, are factory set to the Default value,
and can be adjusted to any value in the Range column.
Read and write access to these setpoint is determined by the Global HMI (Human Machine
Interface) Standard Specification.
Table 1, Setpoint Default and Range
Description Default Range
Unit
Manufacturing Location
Frequency
Voltage
Unit Enable
Unit Status after Power
Failure
Not Selected
60 Hz
460 V
Enable
Not Selected, Europe, USA
50, 60
230, 380, 400, 460, 575
Disable, Enable
Enable Disable, Enable
Control source Local Local, Network
Available Modes Cool
Cool LWT 1
Cool LWT 2
Cool LWT 1 with Glycol
Cool LWT 2 with Glycol
Ice LWT
7.0°C (44.6°F)
7.0°C (44.6°F)
7.0°C (44.6°F)
7.0°C (44.6°F)
-4.0°C (24.8°F)
4.0°C to 15.0°C (39.2°F to 59.0°F)
4.0°C to 15.0°C (39.2°F to 59.0°F)
-4.0°C to 15.0°C (24.8°F to 59.0°F)
-4.0°C to 15.0°C (24.8°F to 59.0°F)
Cool, Cool w/Glycol
Cool/Ice w/Glycol, Ice, Test
-8.0°C to 4.0°C (17.6°F to 39.2°F)
Startup Delta T 2.7 deg C (4.9 deg F) 0 to 5.0 deg C (0 to 9.0 deg F)
Shut Down Delta T 1.5 deg C (2.7 deg F) 0 to 1.7 deg C (0 to 3.1 deg F)
Stage Up Delta T 0.5 deg C (0.9 deg F) 0 to 1.7 deg C (0 to 3.1 deg F)
Stage Down Delta T 0.7 deg C (1.3 deg F) 0 to 1.7 deg C (0 to 3.1 deg F)
Max Pulldown
1.7 deg C/min
(3.1 deg F/min)
0.3 to 2.7 deg C/min
(0.5 to 4.9 deg F/min)
Continued next page.
Description Default Range
Nominal Evap Delta T 2 Cir 5.6 deg C (10.1 deg F) 3.3 to 8.9 deg C (5.9 to 16.0 deg F)
Nominal Evap Delta T 3 Cir 5.6 deg C (10.1 deg F) 3.3 to 10 deg C (5.9 to 18.0 deg F)
Variable Evap Flow No No, Yes
18 OM 1051-2
Evap Recirc Timer 30 sec 0 to 300 seconds
Pump Control #1 Only
#1 Only, #2 Only, Auto,
#1 Primary, #2 Primary
LWT Reset Type None None, 4-20mA, OAT
Max Reset 5.0 deg C (9.0 deg F) 0 to 10.0 deg C (0 to 18.0 deg F)
Start Reset Delta T 5.0 deg C (9.0 deg F) 0 to 10.0 deg C (0 to 18.0 deg F)
Max Reset OAT
Start Reset OAT
15.5°C (59.9°F)
23.8°C (74.8°F)
10.0°C to 30.0°C (50°F to 86.0 °F)
10.0°C to 30.0°C (50°F to 86.0 °F)
Soft Load Off Off, On
Begin Capacity Limit 40% 20-100%
Soft Load Ramp 20 min 1-60 minutes
Demand Limit Off Off, On
Current @ 20mA 800 A 0 to 2000 A
Current limit Setpoint 800 A 0 to 2000 A
# of Circuits 2 2, 3
Ice Delay Timer 12 hrs 1-23 hours
Clear Ice Timer No No, Yes
PVM Multi Point Single Point, Multi Point , None(SSS)
Noise Reduction Disabled Disabled, Enabled
Noise Reduction Start Time 21:00 18:00 – 23:59
Noise Reduction End Time 6:00 5:00 – 9:59
Noise Reduction Offset 5.0 deg C (9.0 deg F) 0 to 14.0 deg C (0 to 25.2 deg F)
Evap LWT Sensor Offset 0 deg C (0 deg F) -5.0 to 5.0 deg C (-9.0 to 9.0 deg F)
Evap EWT Sensor Offset 0 deg C (0 deg F) -5.0 to 5.0 deg C (-9.0 to 9.0 deg F)
OAT Sensor Offset 0 deg C (0 deg F) -5.0 to 5.0 deg C (-9.0 to 9.0 deg F)
Compressors-Global
Start-start timer 20 min 15-60 minutes
Stop-start timer 5 min 3-20 minutes
Pumpdown Pressure 100 kPa (14.5 psi) 70 to 280 kPa (10.2 to 40.6 psi)
Pumpdown Time Limit 120 sec 0 to 180 sec
Light Load Stage Down 40% 26 to 50%
High Load Stage Up 80% 50 to 100%
Stage Up Time 5 min 0 to 60 min
Stage Down Time 3 min 3 to 30 min
Stage Delay Clear No No, Yes
Soft Load Off Off, On
Max # Comps Running 2 2,3
Sequence # Cir 1 1 1-3
Sequence # Cir 2 1 1-3
Sequence # Cir 3 1 1-3
Liquid Injection Activation
85.0°C (185.0°F)
50.0°C to 110.0°C (122.0°C to 230.0°F)
Liq. Line Solenoid Valves No No, Yes
Slide Position Sensors Yes No, Yes
Continued next page.
OM 1051-2 19
Description Default Range
Alarm Limits
Low Pressure-Unload 160 kPa (23 psi) 160 kPa to 310 kPa (23 psi to 48 psi)
Low Pressure-Hold 180 kPa (26 psi) 180 kPa to 310 kPa (26 psi to 48 psi)
Low Press-Unload w/ Glycol 160 kPa (23 psi) 0 kPa to 310 kPa (0 psi to 48 psi)
Low Press-Hold w/Glycol 180 kPa (26 psi) 0 kPa to 310 kPa (0 psi to 48 psi)
High Oil Press Diff Delay 30 sec 10-180 sec
High Oil Press Differential 250 kPa (36 psi) 0 to 415 kPa (0 to 60 psi)
High Discharge Temperature 110.0°C (230.0°F) 65.0 to 110.0 °C (149.0 to 230.0°F)
High Cond Pressure Delay 5 sec 0 to 30 sec
Low Pressure Ratio Delay 90 sec 0 to 180 sec
Start Time Limit 60 sec 20 to 180 sec
Evap. Water Freeze
Evap. Water Freeze w/ Glycol
2.2°C (36.0°F)
2.2°C (36.0°F)
1.1°C to 6.0°C (34.0°F to 42.8°F)
-18.0°C to 6.0°C (-0.4°F to 42.8°F)
Evaporator Flow Proof 15 sec 5 to 15 sec
Recirculate Timeout 3 min 1 to 10 min
Low OAT Lockout
Low OAT Lockout/with
Fan VFD
12.0°C (53.6°F)
12.0°C (53.6°F)
2.0°C to 15.0°C (35.6°F to 59.0°F)
-23.0°C to 15.0°C (-9.4°F to 59.0°F)
The following setpoints exist individually for each circuit:
Description
Default Range
Circuit mode Enable Disable, enable, test
Compressor Size for Non-VFD HSA204
Compressor Size for VFD HSV204
HSA192, HSA204, HSA215
HSA232, HSA241, HSA263
HSV204, HSV215
HSV232, HSV241, HSV263
Economizer (VFD Only) With With, Without
Capacity Control Auto Auto, Manual
Manual Capacity See Note 1 0 to 100%
Clear Cycle Timers No No, Yes
EXV control Auto Auto, manual
Service Pumpdown No No, Yes
Economizer Enable Capacity
(VFD Model Only)
40% 40 to 75%
Evap pressure Sensor offset 0 kPa (0 psi) -100 to 100 kPa (-14.5 to 14.5 psi)
Cond pressure Sensor offset 0 kPa (0 psi) -100 to 100 kPa (-14.5 to 14.5 psi)
Oil pressure Sensor Offset 0 kPa (0 psi) -100 to 100 kPa (-14.5 to 14.5 psi)
Suction temp Sensor Offset 0 deg C (0 deg F) -5.0 to 5.0 deg C (-9.0 to 9.0 deg F)
Discharge temp offset 0 deg C (0 deg F) -5.0 to 5.0 deg C (-9.0 to 9.0 deg F)
Slide sensor mA @ minimum
Slide sensor mA @ maximum
4 mA 4 to 22 mA
20 mA 4 to 22 mA
Fans
Fan VFD enable Enable Disable, Enable
Number of fans 5 5 to 12
Saturated Condenser Temp
Target Min
Saturated Condenser Temp
Target Max
32.0°C (89.6°F)
43.0°C (109.4°F)
20.0°C to 50.0°C (68.0°F to
122.0°F)
32.0°C to 50.0°C (89.6°F to
122.0°F)
Continued next page.
20 OM 1051-2
Description Default Range
Fan Stage 0 Up Deadband 2.5 deg C (4.5 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 1 Up Deadband 2.5 deg C (4.5 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 2 Up Deadband 4.0 deg C (7.2 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 3 Up Deadband 5.0 deg C (9.0 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 4 Up Deadband 4.0 deg C (7.2 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 5 to 12
Up Deadband
4.0 deg C (7.2 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 1 Down Deadband 10.0 deg C (18.0 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 2 Down Deadband 4.0 deg C (7.2 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 3 Down Deadband 3.5 deg C (6.3 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 4 Down Deadband 3.0 deg C (5.4 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 5 Down Deadband 2.5 deg C (4.5 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan Stage 6 to 12
Down Deadband
2.5 deg C (4.5 deg F) 1.0 to 10.0 deg C (1.8 to 18 deg F)
Fan VFD Max Speed 100% 90 to 110%
Fan VFD Min Speed 25% 20 to 60%
Dynamic Default Values
The fan staging dead bands have different default values based on the VFD enable setpoint.
When the VFD enable setpoint is changed, a set of default values for the fan staging dead bands
is loaded as follows:
Fan VFD is Enabled
Setpoint
Default
loaded (oF)
Stage 0 On Deadband 4.5 Stage 0 On Deadband 7.2
Stage 1 On Deadband 4.5 Stage 1 On Deadband 9.0
Stage 2 On Deadband 7.2 Stage 2 On Deadband 9.9
Stage 3 On Deadband 9.0 Stage 3 On Deadband 10.8
Stage 4 On Deadband 7.2 Stage 4 On Deadband 11.7
Stage 5 On Deadband 7.2 Stage 5 On Deadband 11.7
Stage 2 Off Deadband 7.2 Stage 2 Off Deadband 18
Stage 3 Off Deadband 6.3 Stage 3 Off Deadband 14.4
Stage 4 Off Deadband 5.4 Stage 4 Off Deadband 9.9
Stage 5 Off Deadband 4.5 Stage 5 Off Deadband 7.2
Stage 6 Off Deadband 4.5 Stage 6 Off Deadband 7.2
The low pressure settings have different default values based on the Manufacturing Location
setpoint. When the manufacturing location is configured, the default values for these setting are
loaded as shown below:
US Chiller
Setpoint Default loaded
Low Evap Press.Unload 160 kPa (23.2 psi) Low Evap Press. Unload 160 kPa (23.2 psi)
Low Evap Press.-Hold 180 kPa (26.1 psi) Low Evap Pressure-Hold 180 kPa (26.1 psi)
Fan VFD is Disabled
Setpoint
Default
loaded (oF)
European Chiller
Setpoint Default loaded
OM 1051-2 21
Unit Functions
Calculations
EWT Slope
EWT slope is calculated such that the slope represents the change in EWT over a time frame
of one minute.
Pulldown Rate
The slope value calculated above will be a negative value as the water temperature is
dropping. A pulldown rate is calculated by inverting the slope value and limiting to a
minimum value of 0°C/min.
Unit Availability
The unit is available to start if the following conditions are true:
1. Unit switch is closed
2. If unit mode is ice and the ice timer has timed out.
3. No unit alarms exist
4. Emergency stop input is closed
5. At least one circuit is enabled
6. Unit enable setpoint is Enable
7. If remote control is connected and remote unit switch is closed
8. If Control Source = Network, BAS Enable = True
Enabling and disabling the chiller is accomplished using setpoints and inputs to the chiller.
The unit switch, remote switch input, and Unit Enable Setpoint all are required to be on for
the unit to be enabled when the control source is set to local. The same is true if the control
source is set to network, with the additional requirement that the BAS request must be on.
Unit is enabled according to the following table.
NOTE: An x indicates that the value is ignored.
Table 2, Enable Combinations
Unit
Switch
Off x x x x Off
x x Off x x Off
x x x Off x Off
On Local On On x On
x Network x x Off Off
On Network On On On On
Control
Source
Setpoint
Remote
Switch Input
Unit Enable
Setpoint
BAS
Request
Unit
Enable
All of the methods for disabling the chiller, discussed in this section, will cause a normal
shutdown (pumpdown) of any running circuits.
When the controller is powered up, the Unit Enable Setpoint will be initialized to ‘Disable’ if
the Unit Enable Init Setpoint is set to ‘Disable’.
.
22 OM 1051-2
Unit Mode Selection
The operating mode of the unit is determined by setpoints and inputs to the chiller. The
Available Modes Setpoint determines what modes of operation can be used. This setpoint
also determines whether the unit is configured for glycol use. The Control Source Setpoint
determines where a command to change modes will come from. A digital input switches
between cool mode and ice mode if they are available and the control source is set to local.
The BAS mode request switches between cool mode and ice mode if they are both available
and the control source is set to network.
The Available Modes Setpoint must only be changed when the unit switch is off. This is to
avoid changing modes of operation inadvertently while the chiller is running.
Unit Mode is set according to the following table.
Table 3, Mode Combinations
Control Source
Setpoint
x x x Cool Cool
x x x Cool w/Glycol Cool
Local Off x Cool/Ice w/Glycol Cool
Local On x Cool/Ice w/Glycol Ice
Network x Cool Cool/Ice w/Glycol Cool
Network x Ice Cool/Ice w/Glycol Ice
x x x Ice w/Glycol Ice
x x x Test Test
Notes
1. “x” Indicates that the value is ignored.
2. If the Available Modes Setpoint is set to an option ‘w/Glycol’, then glycol operation should be
enabled for the unit. Glycol operation should only be disabled when the Available Modes
Setpoint is set to ‘Cool’.
Mode
Input
BAS
Request
Available Modes
Setpoint
Unit Mode
Glycol Configuration
If the Available Modes Setpoint is set to an option w/Glycol, then glycol operation is
enabled for the unit. Glycol operation must be disabled only when the Available Modes
Setpoint is set to Cool.
Unit Control States
The unit will always be in one of three states:
• Off – Unit is not enabled to run.
• Auto – Unit is enabled to run.
• Pumpdown – Unit is doing a normal shutdown.
Off. The unit should be in the Off state if any of the following are true:
• A unit alarm is active
• All circuits are unavailable to start (cannot start even after cycle timers have expired)
• The unit mode is ice, all circuits are off, and the ice mode delay is active
• Manufacturing Location is not set
• Either manufacturing location or number of circuits have been changed and controller
has not been rebooted
Auto. The unit should be in the Auto state if all of the following are true:
• Manufacturing location is set and controller has been rebooted
• Unit enabled based on settings and switches
• If unit mode is ice, the ice timer has expired
• No unit alarms are active
• At least one circuit is enabled and available to start
OM 1051-2 23
Pumpdown. The unit should be in Pumpdown until all running compressors finish
pumping down if any of the following are true:
• Unit is disabled via settings and/or inputs in section Unit Availability.
• Unit pumpdown alarm is triggered
Unit Status
The displayed unit status is determined by the conditions in the following table:
Table 4, Unit Status
Enum
0 Auto Unit State = Auto
1 Off: Ice Mode Tmr
2 Off: OAT Lockout Unit State = Off and Low OAT Lockout is active
3 Off: All Cir Disabled Unit State = Off and all compressors unavailable
4 Off: Unit Alarm Unit State = Off and Unit Alarm active
5 Off: Keypad Disable Unit State = Off and Unit Enable Setpoint = Disable
6 Off: Remote Sw Unit State = Off and Remote Switch is open
7 Off: BAS Disable
8 Off: Unit Sw Unit State = Off and Unit Switch = Disable
9 Off: Test Mode Unit State = Off and Unit Mode = Test
10 Auto: Noise Reduction Unit State = Auto and Noise Reduction is active
11 Auto: Wait for Load
12 Auto: Evap Recirc Unit State = Auto and Evaporator State = Start
13 Auto: Wait for flow
14 Auto: Pumpdn Unit State = Pumpdown
15 Auto: Max Pulldn
16 Auto: Unit Cap Limit
17 Auto: Current Limit
18 Off. Cfg Chg, Rst Ctlr
19 Off Mfg Loc Not Set Mfg Location is not set
Status Conditions
Unit State = Off, Unit Mode = Ice, and Ice Delay =
Active
Unit State = Off, Control Source = Network, and BAS
Enable = false
Unit State = Auto, no circuits running, and LWT is
less than the active setpoint + startup delta
Unit State = Auto, Evaporator State = Start, and Flow
Switch is open
Unit State = Auto, max pulldown rate has been met or
exceeded
Unit State = Auto, unit capacity limit has been met or
exceeded
Unit State = Auto, unit current limit has been met or
exceeded
Unit configuration setpoint has changed, and reboot
of controller is required
Ice Mode Start Delay
Compressor Staging in Ice Mode
The first compressor will start when evaporator LWT is higher than the target plus the
Startup Delta T setpoint.
When at least one compressor is running, the other compressors will start only when
evaporator LWT is higher than the target plus the Stage Up Delta T setpoint.
All compressors will be staged off when evaporator LWT is less than the target.
Stage Up Delay
A fixed stage up delay of one minute between compressor starts is used in this mode.
When at least one compressor is running, the other compressors will start as quickly as
possible with respect to the stage up delay.
An adjustable start-to-start ice delay timer will limit the frequency with which the chiller
may start in Ice mode. The timer starts when the first compressor starts while the unit is
in ice mode. While this timer is active, the chiller cannot restart in Ice mode. The time
delay is user adjustable.
24 OM 1051-2
The ice delay timer may be manually cleared to force a restart in ice mode. A setpoint
specifically for clearing the ice mode delay is available. In addition, cycling the power to
the controller will clear the ice delay timer.
Evaporator Pump Control
State
Three evaporator pump control states for control of the evaporator pumps:
• Off - No pump on.
• Start – Pump is on, water loop is being recirculated. Recirc timer runnning
• Run – Pump is on, water loop has been recirculated. Recirc timer has timed out
Off The control state is Off when all of the following are true:
• Unit state is Off
• LWT is higher than the Evap Freeze setpoint or LWT sensor fault is active
• EWT is higher than the Evap Freeze setpoint or EWT sensor fault is active
Start. The control state is Start when any of the following are true:
• The unit state is auto
• LWT is less than the Evap Freeze setpoint and LWT sensor fault isn’t active
• EWT is less than the Evap Freeze setpoint and EWT sensor fault isn’t active
Run. The control state is Run when
• The flow switch input has been closed for a time greater than the Evaporator
Recirculate setpoint.
• The flow switch fault is not active
Pump Selection
The pump output used is determined by the Evap Pump Control setpoint. This setting
allows the following configurations:
• #1 only – Pump 1 will always be used
• #2 only – Pump 2 will always be used
• Auto – The primary pump is the one with the least run hours, the other is used as
a backup
• #1 Primary – Pump 1 is used normally, with pump 2 as a backup
• #2 Primary – Pump 2 is used normally, with pump 1 as a backup
Primary/Standby Pump Staging
The standby pump will be on if either of the following are true:
• Pump state is Run and the flow switch is open for Evap Proof Time/2
• Pump start is start and Recirculate timeout has expired.
Auto Control
If auto pump control is selected, the primary/standby logic above is still used. When the
evaporator is not in the run state, the run hours of the pumps will be compared. The
pump with the least hours will be designated as the primary at this time.
Noise Reduction
Noise Reduction is an operating mode designed to reduce unit sound levels by decreasing
compressor and fan operating time. It is used during the night when the cooling load is
usually reduced and the ambient temperature is lower.
Noise Reduction always requires the Noise Reduction setpoint to be set to ‘enable’. If it
is set to ‘disable’, it will not activate for any reason.
Assuming this functionality is enabled, there are two ways it can become active:
OM 1051-2 25
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