Daikin VRV IV RKXYQ5T8Y1B Series Installation And Operation Manual page 40

19 Troubleshooting
Main code
▪ No power is supplied to the compressor unit.
▪ Transmission wiring malfunction
▪ System mismatch. Wrong type of indoor units combined
(R410A, R407C, RA, etc). Indoor unit malfunction
▪ Heat exchanger unit malfunction
▪ Improper type of indoor units are connected.
▪ Mismatch of compressor unit and heat exchanger unit.
▪ The stop valves of the compressor unit are left closed.
▪ The piping and wiring of the specified indoor unit or heat
exchanger unit are not connected correctly to the
compressor unit.
In case of 8 HP:
Main code Sub code
Installation and operation manual
40
Cause
Cause
▪ Heat exchanger fan malfunction.
▪ Drain pump feedback contact is open.
Earth leakage detector activated
Compressor unit: (T1A) - A1P (X101A)
No earth leakage detector detected
Compressor unit: (T1A) - A1P (X101A)
High pressure switch was activated
Compressor unit: (S1PH) - A1P (X4A)
▪ Refrigerant overcharge
▪ Stop valve closed
Stop valve closed (liquid)
▪ Refrigerant overcharge
▪ Stop valve closed
Low pressure malfunction:
▪ Stop valve closed
▪ Refrigerant shortage
▪ Indoor unit malfunction
Electronic expansion valve malfunction (subcool)
Compressor unit: (Y1E) - A1P (X21A)
Electronic expansion valve malfunction (main)
Heat exchanger unit: (Y1E) - A1P (X7A)
Discharge temperature too high:
▪ Stop valve closed
▪ Refrigerant shortage
Compressor unit: (R21T) - A1P (X29A)
▪ Refrigerant overcharge
▪ Stop valve closed
Ambient temperature sensor malfunction
Heat exchanger unit: (R1T) - A1P (X16A)
Discharge temperature sensor malfunction
Compressor unit: (R21T): open circuit - A1P
(X29A)
Discharge temperature sensor malfunction
Compressor unit: (R21T): short circuit - A1P
(X29A)
Solution
▪ Check if all units are powered on.
▪ Check the transmission wiring.
▪ Check if other indoor units have malfunction and confirm
indoor unit mix is allowed.
▪ Check the transmission wiring to the heat exchanger unit.
▪ Check the type of indoor units that are currently
connected. If they are not proper, replace them with
proper ones.
▪ Check if the compressor unit and heat exchanger unit are
compatible.
▪ Open the stop valves on both the gas and liquid side.
▪ Confirm that the piping and wiring of the specified indoor
unit or heat exchanger unit are connected correctly to the
compressor unit.
Solution
In the heat exchanger unit:
▪ Check connection on PCB: A1P (X15A)
▪ Check connection on terminal block (X2M)
▪ Check the fan connectors.
Restart the unit. If the problem reoccurs, contact
your dealer.
Replace the earth leakage detector.
Check stop valve situation or abnormalities in
(field) piping or airflow over air cooled coil.
▪ Check refrigerant amount+recharge unit.
▪ Open stop valves
Open liquid stop valve.
▪ Check refrigerant amount+recharge unit.
▪ Open stop valves.
▪ Open stop valves.
▪ Check refrigerant amount+recharge unit.
▪ Check the user
transmission wiring between the outdoor unit
and the indoor unit.
Check connection on PCB or actuator.
Check connection on PCB or actuator.
▪ 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.
VRV IV compressor unit for indoor installation
interface's display or
RKXYQ5T8 + RKXYQ8T7Y1B
4P499900-1A – 2020.10