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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.

30 codes
CodeWhat it means
E0Flow sensor issue / short circuit
E1Wrong phase rotation / 3-phase sequence error
E2Indoor/outdoor communication line error
E3Direct water temp sensor issue
E4Shell-and-tube HX sensor fault
E5Condenser pipe A sensor malfunction
E6Condenser pipe B sensor malfunction
E7Outdoor temp sensor failure
E8Compressor discharge sensor issue
E9Duct temp sensor (system A) fault
EAMaster/slave comm failure
P0Compressor A temp/pressure out of range
P1Compressor A pressure below limit
P2Compressor B temp/pressure exceeds limit
P3Compressor B pressure dropping
P4System A overcurrent
P5System B overcurrent / voltage fluctuation
P6Condensation temp increased (A)
P7Condensation temp increased (B)
P8Compressor temp rising (overheat)
P9Anti-cold wind protection (heating)
PbFrost protection (auto-defrost)
ECRefrigerant leak detection
EEWater level alarm (cassette/ducted)
EdOutdoor fault protection lockout
F1Room temp sensor fault (indoor)
F2Evaporator sensor fault
F3Condenser sensor fault
F4Outdoor ambient sensor fault
F5Compressor discharge sensor (inverter)

Official Lessar source / manual ↗

Look up any error code — offline — in R-Pro.

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