Lessar Error Codes
Every Lessar error code we have catalogued, with what it means on site — 30 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 Lessar codes
- E0 — Flow sensor issue / short circuit
- E1 — Wrong phase rotation / 3-phase sequence error
- E2 — Indoor/outdoor communication line error
- E3 — Direct water temp sensor issue
- E4 — Shell-and-tube HX sensor fault
- E5 — Condenser pipe A sensor malfunction
- E6 — Condenser pipe B sensor malfunction
- E7 — Outdoor temp sensor failure
| Code | What it means |
|---|---|
| E0 | Flow sensor issue / short circuit |
| E1 | Wrong phase rotation / 3-phase sequence error |
| E2 | Indoor/outdoor communication line error |
| E3 | Direct water temp sensor issue |
| E4 | Shell-and-tube HX sensor fault |
| E5 | Condenser pipe A sensor malfunction |
| E6 | Condenser pipe B sensor malfunction |
| E7 | Outdoor temp sensor failure |
| E8 | Compressor discharge sensor issue |
| E9 | Duct temp sensor (system A) fault |
| EA | Master/slave comm failure |
| P0 | Compressor A temp/pressure out of range |
| P1 | Compressor A pressure below limit |
| P2 | Compressor B temp/pressure exceeds limit |
| P3 | Compressor B pressure dropping |
| P4 | System A overcurrent |
| P5 | System B overcurrent / voltage fluctuation |
| P6 | Condensation temp increased (A) |
| P7 | Condensation temp increased (B) |
| P8 | Compressor temp rising (overheat) |
| P9 | Anti-cold wind protection (heating) |
| Pb | Frost protection (auto-defrost) |
| EC | Refrigerant leak detection |
| EE | Water level alarm (cassette/ducted) |
| Ed | Outdoor fault protection lockout |
| F1 | Room temp sensor fault (indoor) |
| F2 | Evaporator sensor fault |
| F3 | Condenser sensor fault |
| F4 | Outdoor ambient sensor fault |
| F5 | Compressor discharge sensor (inverter) |
Official Lessar source / manual ↗
Frequently asked
What does Lessar error code E0 mean?
Lessar error code E0 means: Flow sensor issue / short circuit. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E1 mean?
Lessar error code E1 means: Wrong phase rotation / 3-phase sequence error. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E2 mean?
Lessar error code E2 means: Indoor/outdoor communication line error. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E3 mean?
Lessar error code E3 means: Direct water temp sensor issue. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E4 mean?
Lessar error code E4 means: Shell-and-tube HX sensor fault. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E5 mean?
Lessar error code E5 means: Condenser pipe A sensor malfunction. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E6 mean?
Lessar error code E6 means: Condenser pipe B sensor malfunction. In R-Pro you also get the likely causes and the inspection steps — offline.
What does Lessar error code E7 mean?
Lessar error code E7 means: Outdoor temp sensor failure. 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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