Grant Aerona fault codes
What each code means, from Grant Aerona's own service literature, and which UK models it applies to.
Grant Aerona heat pumps
P01 (P1)Water flow protection5 modelsP02 (P2)High pressure protection (HP1)5 modelsP03 (P3)Low pressure protection5 modelsP04 (P4)Condenser overheat protection5 modelsP05 (P5)Discharge temperature protection5 modelsP08 (P8)Middle pressure protection5 modelsP11DC fan 1 failure5 modelsP12DC fan 2 failure5 modelsP134-way valve fault5 modelsP14Refrigerant leakage detected5 modelsP21DC water pump abnormal5 modelsP25Outlet pressure sensor failure5 modelsE02 (E2)Discharge temperature sensor (TP) failure5 modelsE03 (E3)Coil temperature sensor (T3) failure5 modelsE04 (E4)Ambient temperature sensor (T4) failure5 modelsE05 (E5)Liquid pipe temperature sensor (T5) failure5 modelsE06 (E6)Return air temperature sensor (TH) failure5 modelsE07 (E7)Water tank temperature sensor (TW) failure5 modelsE08 (E8)Outlet water temperature sensor (TA) failure5 modelsE09 (E9)Outlet water temperature sensor (TB) failure5 modelsE10Hydraulic ↔ refrigerant PCB communication failure5 modelsE13Discharge pressure sensor fault5 modelsE14Low pressure sensor (LPS) failure5 modelsE15DC bus voltage too lowE16DC bus voltage too highE18IPM module abnormalE20Compressor failed to startE21Compressor phase lossE23Compressor over-currentE26Compressor out of stepE29IPM module temperature too highE34AC input voltage abnormal5 modelsE57Gas sensor offline5 modelsE58Gas sensor fault5 models
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