Specifications

48
the unit configuration for digital control, A1.TY Compressor
A1 Digital?
→(Configuration Mode→UNIT) = NO.
If this condition is encountered, check the following items:
• Check for a wiring error.
• Check for a faulty communication bus, or no connection
to the AUX Board.
• Check the AUX Board
• If the unit it is configured for digital control, A1.TY
Compressor A1 Digital?
→(Configuration Mode→UNIT)
is YES, but the unit is not a Digital Capacity machine,
(no digital compressor or AUX Board), this alarm will be
generated.
T176 (4 to 20 mA Reset Input Failure)
— This alert indi-
cates a problem has been detected with reset 4 to 20 mA input.
The input value is either less than 2 mA or greater than 22 mA.
The reset function will be disabled when this occurs.
T177 (4 to 20 mA Demand Limit Input Failure)
— This
alert indicates a problem has been detected with demand limit
4 to 20 mA input. The input value is either less than 2 mA or
greater than 22 mA. The reset function will be disabled when
this occurs.
T200 (Cooler Flow Interlock Contacts Failed to Close at
Start-Up Alert) — This alert indicates the cooler flow switch
interlock 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 start-up. If the unit is equipped with
dual pumps, the second pump will be started and time allowed
to prove flow before the unit is alarmed. The cooler flow/cooler
pump interlock contacts failed to close at start-up alert is gener-
ated and the chiller is not allowed to start.
If this condition is encountered, check the following items:
• Check the chilled water flow switch for proper operation.
• Check the flow switch cable for power and control.
• Check the chilled water loop to be sure that it is com-
pletely filled with water, and all air has been purged.
• Check the chilled water pump interlock circuit for proper
operation.
• Check the pump electrical circuit for power.
• Check the pump circuit breaker.
• Check the pump contactor for proper operation.
• Check the chilled water pump for proper operation.
Look for overload trips.
• Check the chilled water strainer for a restriction.
• Check to be sure that all isolation valves are open com-
pletely.
P201 (Cooler Flow/Interlock Contacts Opened During Nor-
mal Operation Pre-alarm)
T201 (Cooler Flow/Interlock Contacts Opened During Nor-
mal Operation Alert) — This alert will be generated for the
appropriate pump if the chilled water flow switch opens for at
least three (3) seconds after initially being closed, and an P201
- Cooler Flow/Interlock Contacts Opened During Normal Op-
eration Alarm will be generated and the machine will stop. If
available, the other pump will be started. If flow is proven, the
machine will be allowed to restart. If after 5 minutes, the cool-
er flow switch/interlock contacts do not close, the alarm will
change to a T201 - Cooler Flow/Interlock Contacts Opened
During Normal Operation Alert. When this alert is generated
the chiller is shut down.
If this condition is encountered, check the following items:
• Check the chilled water flow switch for proper operation.
• Check the flow switch cable for power and control.
• Check the chilled water loop to be sure that it is
completely filled with water, and all air has been purged.
• Check the chilled water pump interlock circuit for proper
operation.
• Check the pump electrical circuit for power.
• Check the pump circuit breaker.
• Check the pump contactor for proper operation.
• Check the chilled water pump for proper operation.
Look for overload trips.
• Check the chilled water strainer for a restriction.
• Check to be sure that all isolation valves are open
completely.
A202 (Cooler Pump Interlock Closed When Pump Is Off
Alarm) — This alarm will be generated if the unit is config-
ured for CPC=ON Cooler Pump Control, (Configura-
tion
→OPT1) without a call for the Chilled Water Pump,
C.LWP=OFF (Outputs
→GEN.O) and the chilled water switch
is closed, FLOW=ON Cooler Flow Switch (Inputs
→GEN.I)
for 5 minutes. When this alarm is generated the chiller is not al-
lowed to start.
If this condition is encountered, check the following items:
• Check for a wiring error for the chilled water flow
switch, the chilled water flow switch's connection to the
MBB or a wiring error to the chilled water pump.
• Check to see if the chilled water pump control has been
manually bypassed.
• Check for a faulty or grounded chilled water flow switch.
• Check chilled water pump contactor for welded contacts.
T203 (Loss of Communication with the Slave Chiller Alert)
— This alert will be generated if Dual Chiller Control is en-
abled, LLEN=ENBL Lead/Lag Chiller Enable (Configura-
tion
→RSET), the chiller has been configured to be the Master
Chiller MSSL=MAST Master/Slave Select (Configura-
tion
→RSET) and it has not established or lost communication
with the Slave Chiller. When this alert is generated the dual
chiller control will be disabled and the unit will operate in
stand-alone mode.
If this condition is encountered, check the following items:
• Check the communication wiring between the two chill-
ers is proper and is not grounded.
• Check to be sure that both the Master and Slave Chillers
are on the same bus, CCNB CCN Bus Number (Config-
uration
→CCN).
• Check to be sure that the slave chiller address CCNA
CCN Address (Configuration
→CCN) matches what is
programmed in the master chiller's configuration for
slave address. SLVA Slave Address (Configura-
tion
→RSET).
• Check for power at the slave chiller. If power is not pres-
ent, this alarm will be generated.
• Check for a faulty master or slave MBB. If CCN com-
munications is not working, this alarm will be generated.
T204 (Loss of Communication with the Master Chiller
Alert) — This alert will be generated if Dual Chiller Control is
enabled, LLEN=ENBL Lead/Lag Chiller Enable (Configura-
tion
→RSET), the chiller has been configured to be the Slave
Chiller MSSL=SLVE Master/Slave Select (Configura-
tion
→RSET) and it has not established or lost communication
with the Master Chiller. When this alert is generated the dual
chiller control will be disabled and the unit will operate in
stand-alone mode.
If this condition is encountered, check the following items:
• Check the communication wiring between the two chill-
ers is proper and is not grounded.
• Check to be sure that both the master and slave chillers
are on the same bus, CCNB CCN Bus Number (Config-
uration
→CCN).
• Check to be sure that the slave chiller address CCNA
CCN Address (Configuration
→CCN) matches what is
programmed in the master chiller's configuration for
slave address. SLVA Slave Address (Configura-
tion
→RSET).
• Check for power at the master chiller. If power is not
present, this alarm will be generated.