Acson Error Codes
Every Acson error code we have catalogued, with what it means on site — 46 codes in total. In R-Pro, tap any code to get the meaning, likely causes and inspection steps, even with no signal in the plant room.
Common Acson codes
| Code | What it means |
|---|---|
| U0 | Insufficient refrigerant |
| U2 | DC voltage out of range |
| U4 | Communication error |
| U7 | Signal transmission error (outdoor PCB) |
| UA | Installation error |
| UF | Communication error (piping/wiring) |
| UH | Anti-freeze function in other room |
| A1 | Indoor PCB error |
| A3 | Water pump error |
| A5 | Anti-freeze protection |
| A6 | Indoor fan motor abnormal |
| C4 | Indoor heat exchanger thermistor fault |
| C9 | Room thermistor fault |
| E1 | Outdoor PCB error |
| E3 | High pressure protection |
| E4 | Low pressure protection |
| E5 | Compressor motor lock |
| E6 | Compressor start-up error |
| E7 | Outdoor DC fan motor lock |
| E8 | AC input overcurrent |
| E9 | EXV error |
| EA | 4-way valve error |
| F3 | Discharge pipe overheat |
| F6 | Heat exchanger overheat |
| H0 | Compressor sensor system abnormality |
| H3 | High pressure switch error |
| H6 | Position sensor abnormality |
| H8 | AC current sensor error |
| H9 | Outdoor air thermistor fault |
| J1 | Pressure sensor error |
| J3 | Compressor discharge pipe thermistor fault |
| J5 | Suction pipe thermistor fault |
| J6 | Outdoor heat exchanger thermistor fault |
| J7 | Subcooling heat exchanger thermistor fault |
| J8 | Liquid pipe thermistor fault |
| J9 | Gas pipe thermistor abnormality |
| LC | Communication error (control/inverter PCB) |
| L1 | Outdoor PCB error |
| L3 | Electrical box temperature rise |
| L4 | Heat sink overheat |
| L5 | IPM/IGBT error |
| L8 | Electrical thermal switch |
| L9 | Stall prevention |
| P1 | Open phase or voltage unbalance |
| P4 | Heat sink thermistor fault |
| PJ | Capacity setting error |
Official Acson source / manual ↗
Frequently asked
What does Acson error code U0 mean?
Acson error code U0 means: Insufficient refrigerant. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code U2 mean?
Acson error code U2 means: DC voltage out of range. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code U4 mean?
Acson error code U4 means: Communication error. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code U7 mean?
Acson error code U7 means: Signal transmission error (outdoor PCB). In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code UA mean?
Acson error code UA means: Installation error. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code UF mean?
Acson error code UF means: Communication error (piping/wiring). In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code UH mean?
Acson error code UH means: Anti-freeze function in other room. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Acson error code A1 mean?
Acson error code A1 means: Indoor PCB error. In R-Pro you also get the likely causes and the inspection steps — offline.
Look up any error code — offline — in R-Pro.
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