Daikin VRV 5 Series Installation And Operation Manual page 50

21 Troubleshooting
Main Sub code
code
Master Slave 1
Installation and operation manual
50
Cause
Low pressure malfunction:
▪ Stop valve closed
▪ Refrigerant shortage
▪ Indoor unit malfunction
Electronic expansion valve malfunction
(upper heat exchanger) (Y1E) – main PCB
(X21A)
Electronic expansion valve malfunction
(inverter cooling) (Y5E) – main PCB (X23A)
Electronic expansion valve malfunction
(lower heat exchanger) (Y3E) – main PCB
(X22A)
Electronic expansion valve malfunction
(receiver gas) (Y4E) – main PCB (X25A)
Electronic expansion valve malfunction
(subcool heat exchanger) (Y2E) – main PCB
(X26A)
Discharge temperature too high (R21T) –
main PCB (X33A):
▪ Stop valve closed
▪ Refrigerant shortage
Compressor casing temperature too high
(R15T) – main PCB (X33A):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Refrigerant overcharge
▪ Stop valve closed
Ambient temperature sensor malfunction
(R1T) – main PCB (X18A)
Discharge temperature sensor malfunction
(R21T): open circuit – main PCB (X33A)
Discharge temperature sensor malfunction
(R21T): short circuit - main PCB (X33A)
Compressor casing temperature sensor
malfunction (R15T): open circuit - main PCB
(X33A)
Compressor casing temperature sensor
malfunction (R15T): short circuit - main PCB
(X33A)
Suction compressor temperature sensor
(R12T) – sub PCB (X35A)
Suction temperature sensor (R10T) – main
PCB (X29A)
Heat exchanger deicer temperature sensor
(R11T) – sub PCB (X35A)
Upper heat exchanger – gas - temperature
sensor (R8T) – main PCB (X29A)
Lower heat exchanger – gas - temperature
sensor (R9T) main PCB (X29A)
Liquid main - temperature sensor (R3T) –
main PCB (X30A)
Subcool heat exchanger – liquid -
temperature sensor (R7T) - main PCB
(X30A)
Subcool heat exchanger – liquid -
temperature sensor (R16T) - main PCB
(X35A)
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.
Check connection on PCB or actuator
Check connection on PCB or actuator.
Check connection on PCB or actuator.
▪ Open stop valves.
▪ Check refrigerant amount+recharge unit.
▪ 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.
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.
(a) (b)
SVEO SVS
REMA5+REYA8~20A7Y1B
VRV 5 heat recovery
4P684060-1 – 2022.02