Carrier Pro-Dialog Control
60 fault codes documented
A1-01 — Maintenance alert: service number nn
The scheduled preventive maintenance date has passed. This is a reminder to perform necessary servicing.
CT-01 — Contactor stuck, circuit A
A contactor for compressor A1 is stuck, preventing the compressor from shutting down. This could lead to damage. Ventilation and EXV control are maintained, but a second critical fault could cause shutdown.
CT-02 — Contactor stuck, circuit B
A contactor for compressor B1 is stuck, preventing the compressor from shutting down. This could lead to damage. Ventilation and EXV control are maintained, but a second critical fault could cause shutdown.
CT-03 — Contactor stuck, circuit C
A contactor for compressor C1 is stuck, preventing the compressor from shutting down. This could lead to damage. Ventilation and EXV control are maintained, but a second critical fault could cause shutdown.
Co-a1 — Communication loss with compressor A1 board
Communication has been lost with the control board for compressor A1. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-a2 — Communication loss with compressor A2 board
Communication has been lost with the control board for compressor A2. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-a3 — Communication loss with compressor A3 board
Communication has been lost with the control board for compressor A3. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-a4 — Communication loss with compressor A4 board
Communication has been lost with the control board for compressor A4. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-b1 — Communication loss with compressor B1 board
Communication has been lost with the control board for compressor B1. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-b2 — Communication loss with compressor B2 board
Communication has been lost with the control board for compressor B2. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-b3 — Communication loss with compressor B3 board
Communication has been lost with the control board for compressor B3. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-b4 — Communication loss with compressor B4 board
Communication has been lost with the control board for compressor B4. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-c1 — Communication loss with compressor C1 board
Communication has been lost with the control board for compressor C1. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-c2 — Communication loss with compressor C2 board
Communication has been lost with the control board for compressor C2. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-c3 — Communication loss with compressor C3 board
Communication has been lost with the control board for compressor C3. This could be due to a bus fault or a defective slave board. The compressor is shut down.
Co-c4 — Communication loss with compressor C4 board
Communication has been lost with the control board for compressor C4. This could be due to a bus fault or a defective slave board. The compressor is shut down.
P-91 — Free cooling valve position incorrect for circuit A
The 3-way valve for free cooling in circuit A has not reached its correct position within the expected time. The unit will shut down.
P-92 — Free cooling valve position incorrect for circuit B
The 3-way valve for free cooling in circuit B has not reached its correct position within the expected time. The unit will shut down.
P-93 — Free cooling valve position incorrect for circuit C
The 3-way valve for free cooling in circuit C has not reached its correct position within the expected time. The unit will shut down.
P-94 — Operating fault in free cooling, circuit A
There is an operating fault in the free cooling mode for circuit A. The refrigerant pump may not have started correctly or has cavitated. Free cooling mode for this circuit will stop.
P-95 — Operating fault in free cooling, circuit B
There is an operating fault in the free cooling mode for circuit B. The refrigerant pump may not have started correctly or has cavitated. Free cooling mode for this circuit will stop.
P-96 — Operating fault in free cooling, circuit C
There is an operating fault in the free cooling mode for circuit C. The refrigerant pump may not have started correctly or has cavitated. Free cooling mode for this circuit will stop.
P-97 — Reversed entering/leaving water sensors
The water sensors for entering and leaving the heat exchanger appear to be reversed or one may be defective. The unit will be stopped.
Pr-01 — Discharge pressure transducer fault, circuit A
The discharge pressure transducer for circuit A is faulty or has an installation issue. The circuit will be shut down.
Pr-02 — Discharge pressure transducer fault, circuit B
The discharge pressure transducer for circuit B is faulty or has an installation issue. The circuit will be shut down.
Pr-03 — Discharge pressure transducer fault, circuit C
The discharge pressure transducer for circuit C is faulty or has an installation issue. The circuit will be shut down.
Pr-04 — Suction pressure transducer fault, circuit A
The suction pressure transducer for circuit A is faulty or has an installation issue. The circuit will be shut down.
Pr-05 — Suction pressure transducer fault, circuit B
The suction pressure transducer for circuit B is faulty or has an installation issue. The circuit will be shut down.
Pr-06 — Suction pressure transducer fault, circuit C
The suction pressure transducer for circuit C is faulty or has an installation issue. The circuit will be shut down.
Pr-07 — Heat reclaim pressure sensor, circuit A
The pressure sensor for the heat reclaim in circuit A is faulty. The heat reclaim mode for this circuit will be stopped.
Pr-08 — Heat reclaim pressure sensor, circuit B
The pressure sensor for the heat reclaim in circuit B is faulty. The heat reclaim mode for this circuit will be stopped.
Pr-16 — Suction pressure sensor, free cooling refrigerant pump, circuit A
The suction pressure sensor for the free cooling refrigerant pump in circuit A is faulty. The free cooling mode will be stopped.
Pr-17 — Discharge pressure sensor, free cooling refrigerant pump, circuit A
The discharge pressure sensor for the free cooling refrigerant pump in circuit A is faulty. The free cooling mode will be stopped.
Pr-18 — Suction pressure sensor, free cooling refrigerant pump, circuit B
The suction pressure sensor for the free cooling refrigerant pump in circuit B is faulty. The free cooling mode will be stopped.
Pr-19 — Discharge pressure sensor, free cooling refrigerant pump, circuit B
The discharge pressure sensor for the free cooling refrigerant pump in circuit B is faulty. The free cooling mode will be stopped.
Pr-20 — Suction pressure sensor, free cooling refrigerant pump, circuit C
The suction pressure sensor for the free cooling refrigerant pump in circuit C is faulty. The free cooling mode will be stopped.
Pr-21 — Discharge pressure sensor, free cooling refrigerant pump, circuit C
The discharge pressure sensor for the free cooling refrigerant pump in circuit C is faulty. The free cooling mode will be stopped.
V0-xx — Variable speed controller fault, circuit A
There is a fault or alert from the variable speed controller for circuit A. The motor speed will be reduced. The circuit will shut down.
V1-xx — Variable speed controller fault, circuit B
There is a fault or alert from the variable speed controller for circuit B. The motor speed will be reduced. The circuit will shut down.
V2-xx — Variable speed controller fault, circuit C
There is a fault or alert from the variable speed controller for circuit C. The motor speed will be reduced. The circuit will shut down.
XX-01 — Compressor motor temperature too high
The motor temperature for a compressor (e.g., B1) is excessively high. The compressor will be shut down.
XX-02 — Compressor crankcase heater fault
The crankcase heater for a compressor (e.g., B1) is defective or there is a wiring fault. The compressor will be shut down.
XX-03 — Compressor high pressure switch fault
The high-pressure switch for a compressor (e.g., B1) has activated, likely due to low condenser flow, a blocked valve, fan issues, or high entering air/water temperature. The compressor will be shut down.
XX-04 — PTC temperature probe out of range
The PTC temperature probe for a compressor motor (e.g., B1) is reporting an out-of-range value, indicating a defective probe. The compressor will be shut down.
XX-05 — Compressor board power supply disconnected
The power supply to the compressor board (e.g., for B1) has been disconnected or is unstable. The compressor is shut down.
XX-06 — Compressor board and contactor power supply drop
There has been a sudden drop in the power supply to both the compressor board and contactor (e.g., for B1). This can cause damage. The compressor is shut down.
th-01 — Sensor fault, fluid entering water heat exchanger
The temperature sensor for the fluid entering the water heat exchanger is faulty. The unit will shut down until the sensor is repaired or replaced.
th-02 — Sensor fault, fluid leaving water heat exchanger
The temperature sensor for the fluid leaving the water heat exchanger is faulty. The unit will shut down until the sensor is repaired or replaced.
th-03 — Defrost fault, circuit A
A defrosting issue has been detected in circuit A. The circuit will shut down if the unit is in heating mode.
th-04 — Defrost fault, circuit B
A defrosting issue has been detected in circuit B. The circuit will shut down if the unit is in heating mode.
th-08 — Heat reclaim condenser inlet sensor fault
The temperature sensor for the heat reclaim condenser inlet is faulty. The heat reclaim mode will be stopped.
th-09 — Heat reclaim condenser outlet sensor fault
The temperature sensor for the heat reclaim condenser outlet is faulty. The heat reclaim mode will be stopped.
th-10 — Outside temperature sensor fault
The sensor measuring the outside temperature is faulty. The unit will shut down until the sensor is repaired or replaced.
th-11 — CHWS fluid sensor fault (master/slave)
The CHWS (Chilled Water Supply) fluid sensor in the master/slave configuration is faulty. The master/slave mode will be stopped.
th-12 — Suction sensor fault, circuit A
The suction sensor for circuit A is faulty. The circuit will be shut down.
th-13 — Suction sensor fault, circuit B
The suction sensor for circuit B is faulty. The circuit will be shut down.
th-14 — Suction sensor fault, circuit C
The suction sensor for circuit C is faulty. The circuit will be shut down.
th-18 — Condenser subcooling liquid sensor fault, circuit A
The condenser subcooling liquid sensor for circuit A is faulty. The heat reclaim mode for this circuit will be stopped.
th-19 — Condenser subcooling liquid sensor fault, circuit B
The condenser subcooling liquid sensor for circuit B is faulty. The heat reclaim mode for this circuit will be stopped.
th-21 — Room temperature sensor fault
The sensor measuring the room temperature is faulty. Set-point control by the thermostat will be stopped.