Daikin VRV IV Installer And User Reference Manual page 143

Main code
Master
RXMLQ8 + RXYLQ10~14T7Y1B*
VRV IV system air conditioner
4P543427-1A – 2020.10
Sub code
Slave 1 Slave 2
Cause
Low pressure malfunction:
▪ Stop valve closed
▪ Refrigerant shortage
▪ Indoor unit malfunction
Electronic expansion valve
malfunction (subcool) (Y2E) -
A1P (X21A)
Electronic expansion valve
malfunction (main) (Y1E) - A1P
(X23A)
Electronic expansion valve
malfunction (storage vessel)
(Y3E) - A1P (X22A)
Discharge temperature too
high (R21T/R22T):
▪ Stop valve closed
▪ Refrigerant shortage
Compressor casing
temperature too high (R8T):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Refrigerant overcharge
▪ Stop valve closed
Ambient temperature sensor
malfunction (R1T) - A1P
(X18A)
24 Troubleshooting
|
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
▪ 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.
Installer and user reference guide
143