Daikin VRV IV+ RYYQ12U7Y1B Series Installer And User Manual page 51

Main code
Master
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
Sub code
Slave 1 Slave 2
Discharge temperature too high
(R21T/R22T):
▪ Stop valve closed
▪ Refrigerant shortage
Compressor casing temperature too
high (R8T/R9T):
▪ Stop valve closed
▪ Refrigerant shortage
▪ Refrigerant overcharge
▪ Stop valve closed
Ambient temperature sensor
malfunction (R1T) - A1P (X18A)
Discharge temperature sensor
malfunction (R21T): open circuit - A1P
(X19A)
Discharge temperature sensor
malfunction (R21T): short circuit - A1P
(X19A)
Discharge temperature sensor
malfunction (R22T): open circuit - A1P
(X19A)
Discharge temperature sensor
malfunction (R22T): short circuit - A1P
(X19A)
Compressor casing temperature
sensor malfunction (R8T): open circuit
- A1P (X19A)
Compressor casing temperature
sensor malfunction (R8T): short circuit
- A1P (X19A)
Compressor casing temperature
sensor malfunction (R9T): open circuit
- A1P (X19A)
Compressor casing temperature
sensor malfunction (R9T): short circuit
- A1P (X19A)
Suction temperature sensor
malfunction (R3T) - A1P (X30A)
De-icing temperature sensor
malfunction (R7T) - A1P (X30A)
Liquid temperature sensor (after
subcool HE) malfunction (R5T) - A1P
(X30A)
Liquid temperature sensor (coil)
malfunction (R4T) - A1P (X30A)
Gas temperature sensor (after subcool
HE) malfunction (R6T) - A1P (X30A)
High pressure sensor malfunction
(S1NPH): open circuit - A1P (X32A)
High pressure sensor malfunction
(S1NPH): short circuit - A1P (X32A)
Low pressure sensor malfunction
(S1NPL): open circuit - A1P (X31A)
Low pressure sensor malfunction
(S1NPL): short circuit - A1P (X31A)
Cause
▪ 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.
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.
10 Troubleshooting
Solution
Installer and user reference guide
51