ACSON Air Conditioner Error Codes

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Error Codes for Wall-Mounted Inverter Units

Error codes are displayed as indicated below, accompanied by a long beep.

Error Codes and Solutions

Error Code	Solution
E1	Loose/short-circuited ambient air sensor contact. Check the room sensor connection/replace the room sensor.
E2	Open indoor coil sensor contact. Check the indoor coil sensor connection/replace the indoor coil sensor.
E3	Open outdoor coil sensor contact. Check the outdoor coil sensor connection/replace the outdoor coil sensor.
E4	Compressor overload protection/indoor or outdoor coil sensor short-circuited. If running amperage is too high, replace the compressor; otherwise, replace the coil sensor.
E5	Gas leakage. Check for leaks, repair, and recharge refrigerant.
E6	Pump failure. Clear blockages in the drainage pipe. If the pump is not working, replace it.
E7	Outdoor coil sensor present (MS model). Remove the outdoor coil sensor.
E8	Hardware error (touch switch pin short-circuited). Check the condition of the touch switch pin.
E9	No feedback from the indoor fan. Check the indoor fan motor/its wiring.
EE	EEPROM defrosting.

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Error Codes for G18 and GS02 – Inverter Models

Error Code	Issue
00	Normal operation.
U0	Insufficient gas.
U2	DC voltage out of range.
U4	Communication error.
U7	Signal transmission error (on outdoor unit PCB).
UA	Installation error.
UF	Communication error (indoor and outdoor), piping, or wiring issue.
OH	Anti-freeze function active in another room.
A1	Indoor PCB error.
A3	Water pump error.
A5	Anti-freeze activation.
A6	Abnormal indoor fan motor.
C4	Indoor heat exchanger thermistor short/open.
C9	Indoor ambient thermistor short/open.
E1	Outdoor PCB error.
E3	High-pressure protection.
E4	Low-pressure protection.
E5	Compressor motor lock.
E6	Compressor startup error.
E7	Outdoor DC fan motor lock.

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Multi-Compressors with Sequential Controller

Error Code	Issue
E01	Manual reset required (possible causes).
E02	Compressor 1 high temperature (overload).
E03	Compressor 2 high temperature (overload).
E04	Compressor 3 high temperature (overload).
E05	Compressor 4 high temperature (overload).
E06	Compressor 1 high-pressure trip/open contact.
E07	Compressor 2 high-pressure trip/open contact.
E08	Compressor 3 high-pressure trip/open contact.
E09	Compressor 4 high-pressure trip/open contact.
E10	Compressor 1 trip/low refrigerant level/abnormal outdoor unit.
E11	Compressor 2 trip/low refrigerant level/abnormal outdoor unit.
E12	Compressor 3 trip/low refrigerant level/abnormal outdoor unit.
E13	Compressor 4 trip/low refrigerant level/abnormal outdoor unit.
E14	Room sensor short-circuited.
E15	Room sensor open.

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Error Diagnosis via Wired Controller

Error Code	Meaning
F3	Broken sensor (indoor outlet coil).
F4	Broken sensor (indoor return air).
F5	Broken sensor (indoor supply air).
F6	Communication failure between indoor unit and controller.
F7	Ambient temperature exceeds the limit.
F8	4WV malfunction.
F9	Refrigerant leakage.
FA	Controller storage failure.
FC	Indoor and outdoor communication failure.

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R410A Multi-Digital Scroll System (MDS-B Series)

Error Code	Meaning
EC00	00## indoor unit communication.
EC01	01# indoor unit communication failure.
ER48	Digital compressor overload.
ER49	Fix 1 compressor overload.
ER50	Fix 2 compressor overload.
ER51	Fix 3 compressor overload.
ER52	Discharge pressure too high.
ER53	Suction pressure too low.
ER54	Outdoor unit IC error.
ER55	System error.