8 Troubleshooting
Installation and operation manual
22
5TMV1B
VRV IV-S system air conditioner
4P399985-1B – 2015.06
8
Troubleshooting
8.1
Solving problems based on error
codes
In case of a displayed malfunction code, perform correcting actions
as explained in the malfunction code table.
After correcting the abnormality, press BS3 to reset the malfunction
code and retry operation.
INFORMATION
If a malfunction occurs, the error code is displayed on the
user interface of the indoor unit.
8.1.1
Error codes: Overview
Main code
Cause
Solution
▪ The stop valve of an outdoor unit is left closed.
▪ Refrigerant overcharge
▪ Open the stop valve on both the gas and liquid side.
▪ Recalculate the required amount of refrigerant from the
piping length and correct the refrigerant charge level by
recovering any excessive refrigerant with a refrigerant
recovery machine.
▪ The stop valve of an outdoor unit is left closed.
▪ Insufficient refrigerant
▪ Open the stop valve on both the gas and liquid side.
▪ Check if the additional refrigerant charge has been
finished correctly. Recalculate the required amount of
refrigerant from the piping length and add an adequate
amount of refrigerant.
Electronic expansion valve malfunction
(Y1E) - A1P (X21A)
(Y3E) - A1P (X22A)
Check connection on PCB or actuator.
▪ The stop valve of an outdoor unit is left closed.
▪ Insufficient refrigerant
▪ Open the stop valve on both the gas and liquid side.
▪ Check if the additional refrigerant charge has been
finished correctly. Recalculate the required amount of
refrigerant from the piping length and add an adequate
amount of refrigerant.
Refrigerant overcharge
Recalculate the required amount of refrigerant from the
piping length and correct the refrigerant charge level by
recovering any excessive refrigerant with a refrigerant
recovery machine.
Ambient temperature sensor malfunction (R1T) - A1P
(X11A)
Check connection on PCB or actuator.
Discharge temperature sensor malfunction (R2T): open
circuit / short circuit - A1P (X12A)
Check connection on PCB or actuator.
Suction temperature sensor malfunction
(R3T) - A1P (X12A)
(R5T) - A1P (X12A)
Check connection on PCB or actuator.
Liquid temperature sensor (coil) malfunction (R4T) - A1P
(X12A)
Check connection on PCB or actuator.
Liquid temperature sensor (after subcool HE) malfunction
(R7T) - A1P (X13A)
Check connection on PCB or actuator.
Gas temperature sensor (after subcool HE) malfunction
(R6T) - A1P (X13A)
Check connection on PCB or actuator.
High pressure sensor malfunction (S1NPH): open circuit /
short circuit - A1P (X17A)
Check connection on PCB or actuator.
Low pressure sensor malfunction (S1NPL): open circuit /
short circuit - A1P (X18A)
Check connection on PCB or actuator.
Transmission outdoor unit - inverter: INV1 / FAN1
transmission trouble
Check connection.
INV1 unbalanced power supply voltage
Check if power supply is within range.
Insufficient supply voltage
Check if the supply voltage is supplied properly.
Malfunction code: System test run not yet executed (system
operation not possible)
Execute system test run.
No power is supplied to the outdoor unit.
Check if the power wiring for the outdoor unit is connected
correctly.
Faulty wiring to Q1/Q2
Check Q1/Q2 wiring.