Daikin RDXYQ5T8V1B Installer And User Manual page 128

22 | Troubleshooting
Main code Sub code
Installer and user reference guide
128
Cause
Low pressure malfunction:
▪ Stop valve closed
▪ Refrigerant shortage
▪ Indoor unit malfunction
Electronic expansion valve malfunction
(subcool)
Compressor unit: (Y1E) - A1P (X21A)
Electronic expansion valve malfunction
(main)
Heat exchanger unit: (Y1E) - A1P (X7A)
Discharge temperature too high:
▪ Stop valve closed
▪ Refrigerant shortage
Compressor unit: (R21T) - A1P (X29A)
▪ Refrigerant overcharge
▪ Stop valve closed
Ambient temperature sensor
malfunction
Heat exchanger unit: (R1T) - A1P (X16A)
Discharge temperature sensor
malfunction
Compressor unit: (R21T): open circuit -
A1P (X29A)
Discharge temperature sensor
malfunction
Compressor unit: (R21T): short circuit -
A1P (X29A)
Heat exchanger gas sensor malfunction
Heat exchanger unit: (R2T) - A1P (X18A)
Suction temperature sensor
malfunction
Compressor unit: (R3T) - A1P (X30A)
Suction temperature sensor
malfunction
Compressor unit: (R7T) - A1P (X30A)
De-icing temperature sensor
malfunction
Heat exchanger unit: (R3T) - A1P (X17A)
Solution
▪ Open stop valves.
▪ Check refrigerant amount+recharge
unit.
▪ Check the user interface's display or
transmission wiring between the
outdoor unit and the indoor unit.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
▪ Open stop valves.
▪ Check refrigerant amount+recharge
unit.
▪ Check refrigerant amount+recharge
unit.
▪ Open stop valves.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
Check connection on PCB or actuator
RKXYQ5T8+8T7Y1B + RDXYQ5T8+8T7V1B
VRV IV heat pump for indoor installation
4P499898-1B – 2021.12