Category
Boilers
Boiler fault codes with evidence-led diagnosis.
314 published entries
Brands in boilers
All brands
Published error entries
2971Junkers Bosch 2971 on a gas boiler: water pressure too lowMedium· Junkers810Junkers Bosch 810 on a gas boiler: hot water stays coldMedium· Junkers811Junkers 811 gas boiler: hot water disinfection failedMedium· Junkers9UJunkers 9U on a gas boiler: HCM coding plug fault code 233Medium· JunkersA0Junkers A0 on gas water heater: inlet and outlet sensorsMedium· JunkersA1Junkers A1 on a gas boiler: pump blocked or running on airMedium· JunkersA7Junkers A7 on a gas boiler: hot water temperature sensor faultMedium· JunkersA8Junkers A8 on a gas boiler: EMS or BUS communication faultMedium· JunkersCAJunkers CA gas water heater: water flow above the maximumMedium· JunkersD1Junkers D1 on a gas boiler: return temperature sensor faultMedium· JunkersD3Junkers d3 on a gas boiler: external controller TB1 trippedMedium· JunkersD4Junkers D4 on a gas boiler: water temperature rising too fastMedium· JunkersE2Junkers E2 on a gas boiler: flow temperature sensor faultMedium· JunkersECJunkers EC gas water heater: flame lost while runningMedium· JunkersEFJunkers EF on a gas boiler: boiling detected in the heatingMedium· JunkersFDJunkers FD boiler code: power cut or reset pressed by mistakeMedium· JunkersH07Junkers H07 boiler code: heating water pressure too lowMedium· JunkersH11Junkers H11 on a gas boiler: hot water outlet sensor warningMedium· JunkersF37Lamborghini F37 on a gas boiler: system water pressure is lowMedium· Lamborghini CaloreclimaE515Navien E515 on a tankless water heater: abnormal PCB operationMedium· Navien79Rinnai 79 on a tankless water heater: water leak detectedMedium· RinnaiLCRinnai LC on a tankless water heater: scale build-upMedium· RinnaiF00Saunier Duval F.00 on a gas boiler: flow sensor open circuitMedium· Saunier DuvalF10Saunier Duval F.10 on a gas boiler: flow sensor short circuitMedium· Saunier DuvalF22Saunier Duval F.22 on a gas boiler: low water safety shutdownMedium· Saunier DuvalF23Saunier Duval F.23 on a gas boiler: temperature spread too highMedium· Saunier DuvalF24Saunier Duval F.24 on a gas boiler: temperature rising too fastMedium· Saunier DuvalF49Saunier Duval F.49 on a gas boiler: eBUS connection faultMedium· Saunier DuvalF71Saunier Duval F.71 on a gas boiler: flow sensor reading stuckMedium· Saunier DuvalF72Saunier Duval F72 on a gas boiler: flow/return NTC faultMedium· Saunier DuvalF73Saunier Duval F.73 on a gas boiler: pressure sensor too lowMedium· Saunier DuvalF74Saunier Duval F74 boiler: water pressure sensor wiring faultMedium· Saunier DuvalF83Saunier Duval F.83 on a gas boiler: no sensor temperature riseMedium· Saunier DuvalF84Saunier Duval F84 boiler code: flow and return sensors disagreeMedium· Saunier DuvalErr 10Thermor electric water heater Err 10: display link board faultMedium· ThermorW15Thermor W15 water heater code: date and time not set or lostMedium· ThermorW21Thermor W21 water heater code: air inlet or evaporator sensorMedium· ThermorW23Thermor electric water heater W23: water sensor control faultMedium· ThermorW25Thermor W25 on an Aeromax water heater: compressor supply or operation faultMedium· ThermorW30Thermor W30.1 water heater code: heat pump heating too slowlyMedium· ThermorW7Thermor W7 on a water heater: ACI Hybrid protection circuit faultMedium· ThermorF00Vaillant F.00 on an ecoTEC boiler: flow sensor interruptionMedium· VaillantF01Vaillant F.01 on a gas boiler: return sensor interruptionMedium· VaillantF10Vaillant F.10 on a gas boiler: flow sensor short circuitMedium· VaillantF11Vaillant F.11 on a gas boiler: return sensor short circuitMedium· VaillantF13Vaillant F13 boiler fault: hot water cylinder sensor shortMedium· VaillantF164Vaillant F.164 on a gas water heater: 45 minute run limitMedium· VaillantF168Vaillant F.168 on a gas water heater: water leak sensor faultMedium· Vaillant