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19
6.4 - Alarm codes
Alarm
No.
Alarm
code
Alarm description
Reset type
Probable cause
Action taken by the control
Thermistor faults
1
th-01 Sensor fault, fluid entering water heat
exchanger
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
2
th-02 Sensor fault, fluid leaving water heat
exchanger
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
3
th-03 Defrost sensor fault, circuit A
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
4
th-04 Defrost sensor fault, second coil
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
5
th-10 Outside temperature sensor fault
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
6
th-11 CHWS fluid sensor fault (master/slave) Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
The master/slave mode is
stopped
7
th-12 Suction sensor fault
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
8
th-24 Economiser sensor fault
Automatic when the temperature
measured by the sensor returns to normal
Defective thermistor
Unit is shut down
Pressure transducer faults
9
Pr-01 Discharge pressure transducer fault
Automatic when the voltage transmitted
by the sensor returns to normal
Defective transducer or connection
fault
Unit is shut down
10
Pr-04 Suction pressure transducer fault
Automatic when the voltage transmitted
by the sensor returns to normal
Defective transducer or connection
fault
Unit is shut down
11
Pr-13 Economiser pressure transducer fault Automatic when the voltage transmitted
by the sensor returns to normal
Defective transducer or connection
fault
Unit is shut down
12
Pr-24 Water pump pressure transducer fault Automatic when the voltage transmitted
by the sensor returns to normal
Defective transducer or connection
fault
Unit is shut down
Communication fault
13
Co-E1 Communication loss with the EXV
board
Automatic when communication is
re-established
Installation bus fault or defective
slave board
Unit is shut down
14
Co-O1 Communication loss with PD-AUX
board No.1
Automatic when communication is
re-established
Installation bus fault or defective
slave board
Unit with optional water pressure
sensors, unit is shut down.
15
Co-O2 Communication loss with PD-AUX
board No. 2
Automatic when communication is
re-established
Installation bus fault or defective
slave board
None
16
A1-01 CP A1 fault: Kriwan electrical
protection open
Manual
Compressor overheating
Compressor is shut down
17
A2-01 CP A2 fault: Kriwan electrical
protection open
Manual
Compressor overheating
Compressor is shut down
Process faults
18
P-01 Water heat exchanger frost protection. Automatic if the same alarm has not tripped
during the last 24 hours, otherwise manual.
Water flow rate too low or defective
thermistor
Unit is shut down
19
P-05 Low suction temperature.
Automatic when the temperature returns to
normal, and if this alarm has not appeared
during the last 24 hours, otherwise manual.
Pressure sensor defective, EXV
blocked or low refrigerant charge
Unit is shut down
20
P-08
High superheat
Automatic when the temperature returns to
normal, and if this alarm has not appeared
during the last 24 hours, otherwise manual.
Pressure sensor defective, EXV
blocked or low refrigerant charge
Unit is shut down
21
P-11 Low superheat
Automatic when the temperature returns to
normal, and if this alarm has not appeared
during the last 24 hours, otherwise manual.
Pressure sensor defective, EXV
blocked or low refrigerant charge
Unit is shut down
22
P-14 Water flow control and customer
interlock fault
Automatic if the unit is in manual
shut-down status, otherwise manual.
Heat exchanger pump defect or
water flow switch fault
Unit is shut down, if the alarm
occurs in defrost mode, if not
the unit remains on.
23
P-16
Compressor A1 not started or no
pressure increase registered
Manual
Connection problem
Compressor is shut down
24
P-17
Compressor A2 not started or no
pressure increase registered
Manual
Connection problem
Compressor is shut down
25
P-29
Communication loss with the System
Manager
Automatic when communication is
re-established
CCN installation bus defective
Unit goes into autonomous
mode
26
P-30
Communicaiton loss between master
and slave
Automatic when communication is
re-established
CCN installation bus defective
Unit goes into autonomous
mode
27
P-31
CCN emergency stop
Manual
Network command
Unit is shut down
28
P-32 Fault water pump 1
Manual
Pump overheating or poor pump
connection
Unit is completely stopped if
there is no emergency pump
29
P-37
Repeated high pressure unloading
Automatic
Transducer defective or fan circuit fault None
30
P-40
Repeated low suction temperature
unloading
Manual
Pressure sensor defective or
refrigerant charge too low
Unit is shut down
31
P-43
Heat exchanger temperature too low,
less than 8°C, prevents unit start-up
Automatic when the temperature detected
returns to normal
Operating compressor protection
out of range or pressure sensor fault
The unit cannot start
32
P-50
Refrigerant leak
Automatic when the concentration returns
to a lower value than the normal threshold
Refrigerant leak or volatile
components present in the machine
atmosphere
None
33
P-63
High pressure fault
Manual
Fan fault
Unit is shut down
34
P-97
Reversed entering/leaving water sensors Manual
Sensor defective, sensors reversed Unit is shut down
35
MC-nn Master chiller configuration error
Automatic when the master configuration
returns to normal or when the unit is no
longer in master/slave mode
Master/slave configuration error
Master/slave mode is stopped
36
FC-nO No factory configuration
Automatic if the configuration is entered
Unit size has not been configured
Unit is shut down