DIAGNOSTIC CODES
No.
1
2
3
4
5
6
Description
If outdoor unit detects the high pressure switch is cut off for 3-sec
successively, high pressure protection will occur. All the loads
(except the 4-way valve in heating mode) will be switched off.
In this case, all the buttons and remote control signals except
ON/OFF button will be disabled and system won't be recovered
automatically. Switch off the unit or re-energize the unit after
cutting off power to eliminate this protection.
If indoor unit detects the evaporator temperature is lower than
protective temperate value after the unit has been running for a
period of time under cooling or dry mode, the unit will report this fault,
in which case the compressor and outdoor fan motor will be stopped.
The unit will not run until evaporator temperature is higher than
the protective temp. value and the compressor is stopped for 3-min.
If outdoor unit detects low-pressure switch is open during ON or
standby state within 30-sec successively the unit will report a low
pressure protection. If the fault occurs 3 times successively within
30-min, the unit will not recover automatically.
If the unit reports low refrigerant level within 10-min after turning on
the unit, the unit will stop operation. If the fault occurs successively
3 times, the unit cannot be recovered automatically.
If the unit enters refrigerant recovery mode through special
operation, E3 will be displayed. After exiting refrigerant recovery
mode, the code will disappear.
If outdoor unit detects the discharge temperature is higher than
protective temperature value, the unit will report high discharge
temperature protection. If the protection occurs over 6 times, the
unit cannot be recovered automatically. Switch off the unit or
re-energize the unit after cutting off power to reset this protection.
If the outdoor unit does not receive data from indoor unit,
communication malfunction will be reported. If there is
communication abnormality between display board and indoor
unit, communication malfunction will be reported.
If the indoor unit does not receive signal from indoor fan motor
for 30-sec successively when the fan motor is operating, indoor
fan motor malfunction will be reported. In this case, the unit can
automatically resume operation after stopping. If the malfunction
occurs 6 times within one hour, the unit cannot be recovered
automatically. Switch off the unit or re-energize the unit after
cutting off power to eliminate this malfunction.
Error
Code
E1
E2
E3
E4
E6
E8
Malfunction
Name
High Pressure
Protection
Indoor Coil
Freeze
Protection
Low Pressure
Protection
Low
Refrigerant
Protection
Refrigerant
Recycling
Mode
Compressor
High Discharge
Temperature
Protection
Communication
Malfunction
Origin of
Malfunction
High Pressure
Switch
Indoor
Evaporator
Temperature
Sensor
Low Pressure
Switch
Compressor
Discharge
Temperature
Communication
Failure Between
Indoor and
Outdoor Main
Board
Indoor
Fan Motor
Error Codes
The U-Match System has on board diagnostics. The indoor unit and Tether Controller will display
error codes. The following is a summary of the codes with explanation:
31
