Daikin VRV IV - Page 143

24 | Troubleshooting
Installer and user reference guide
143
RXMLQ8 + RXYLQ10~14T7Y1B*
VRV IV system air conditioner
4P543427-1A – 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 (subcool) (Y2E) -
A1P (X21A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (main) (Y1E) - A1P
(X23A)
Check connection on PCB or
actuator.
Electronic expansion valve
malfunction (storage vessel)
(Y3E) - A1P (X22A)
Check connection on PCB or
actuator
Discharge temperature too
high (R21T/R22T):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Open stop valves.
▪ Check refrigerant amount
+recharge unit.
Compressor casing
temperature too high (R8T):
▪ 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) - A1P
(X18A)
Check connection on PCB or
actuator.