Daikin VRV IV+ - Page 155

24 | Troubleshooting
Installer and user reference guide
155
REYQ8~20+REMQ5U7Y1B
VRV IV+ heat recovery
4P561154-1A – 2020.10
Main code Sub code Cause Solution
Master Slave 1 Slave 2
Low pressure malfunction:
▪ Stop valve closed
▪ Refrigerant shortage
▪ Indoor unit malfunction
▪ 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.
Electronic expansion valve
malfunction (upper heat
exchanger) (Y1E) – main PCB
(X21A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (lower heat
exchanger) (Y3E) – main PCB
(X23A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (subcool heat
exchanger) (Y2E) – main PCB
(X22A)
Check connection on PCB or
actuator
Electronic expansion valve
malfunction (receiver gas) (Y4E)
– main PCB (X25A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (inverter cooling)
(Y5E) – sub PCB (X8A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (auto charge) (Y6E)
- sub PCB (X10A)
Check connection on PCB or
actuator.
Discharge temperature too high
(R21T/R22T) – main PCB
(X19A):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Open stop valves.
▪ Check refrigerant amount
+recharge unit.
Compressor casing
temperature too high (R15T) –
main PCB (X19A):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Open stop valves.
▪ Check refrigerant amount
+recharge unit.
▪ Refrigerant overcharge
▪ Stop valve closed
▪ Check refrigerant amount
+recharge unit.
▪ Open stop valves.
Ambient temperature sensor
malfunction (R1T) – main PCB
(X18A)
Check connection on PCB or
actuator.