All fault codes

Fujitsu Waterstage fault codes

What each code means, from Fujitsu Waterstage's own service literature, and which UK models it applies to.

Fujitsu Waterstage heat pumps

30Flow sensor mixing circuit4 models 83BSB short circuit4 models 212Internal communication failure4 models 441BX31 no function4 models 442BX24 no function4 models 443BX33 no function4 models 444BX34 no function4 models 516Heat pump missing4 models 11Serial communication error1 model 23Combination error1 model 32UART communications error4 models 42Hydraulic unit heat exchanger thermistor error4 models 62Outdoor unit main PCB error1 model 63Inverter error1 model 71Discharge thermistor error1 model 72Compressor thermistor error1 model 73Heat exchanger thermistor (outlet) error1 model 74Outdoor thermistor error1 model 77Heat sink thermistor error (PFC)4 models 78Expansion valve thermistor error1 model 84Current sensor error1 model 86Pressure sensor error / Pressure switch error1 model 94Current trip (permanent stoppage)1 model 95Detection of compressor position error (permanent stoppage)1 model 97Outdoor unit fan motor error1 model A1Discharge temperature protection (permanent stoppage)1 model A3Compressor temperature protection (permanent stoppage)1 model A5Low pressure abnormal4 models ACOutdoor unit radiator temperature error4 models 1/1Communication error between hydraulic unit and outdoor unit 2/3Connection forbidden (series error)3 models 3/1Indoor unit power supply abnormal3 models 3/2Serial communication error between controller PCB and interface PCB 4/1Heat pump capacity signal error (open or short)4/2Hydraulic indoor unit heat exchanger thermistor error 6/1Outdoor unit power supply abnormal3 models 6/2Outdoor unit main PCB error3 models 6/3Inverter error 6/4Active filter error 6/5Outdoor unit IPM error3 models 6/7Outdoor unit power short interruption error (protective operation)3 models 6/8Outdoor unit magnetic relay error3 models 7/1Discharge thermistor error 7/2Compressor thermistor error 7/3Heat exchanger thermistor (outlet/intermediate) error 7/4Outdoor thermistor error 7/7Outdoor unit heat sink temperature thermistor error 7/8Expansion valve thermistor error 8/4Current sensor error3 models 8/6Pressure sensor error / pressure switch error 9/4Current trip 9/5Detection of compressor position error / compressor start-up error 9/7Outdoor unit fan motor 1 error 9/8Outdoor unit fan motor 2 error3 models 10/1Discharge temperature protection 10/3Compressor temperature protection 10/4Outdoor unit pressure error3 models 10/5Low pressure abnormal 10/9Current overload error3 models cont. 1s/1sPump-down operation (not a fault)3 models cont. on / offDefrosting (not a fault)3 models 1 flashSerial forward transfer error 2 flashesDischarge thermistor error 3 flashesPressure sensor error 4 flashesHeat-exchange thermistor (outlet) error 6 flashesExpansion valve thermistor error 7 flashesOutdoor temperature thermistor error 8 flashesCompressor thermistor error 9 flashesHeat sink thermistor error 11 flashesDischarge temperature protection (permanent stoppage)12 flashesCompressor temperature protection (permanent stoppage)13 flashesCurrent trip (permanent stoppage)14 flashesDetection of compressor position error (permanent stoppage) — 3-phase outdoor only 15 flashesCompressor start-up error (permanent stoppage)16 flashesFan motor (1) error (permanent stoppage)17 flashesFan motor (2) error (permanent stoppage)18 flashesInverter error 20 flashesLow pressure abnormal 23 flashesDischarge pressure sensor error3 models 24 flashesSuction pressure sensor error3 models

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