Boiler Fault Codes

Vaillant ecoTec exclusive Green iQ combi boiler error codes

Code Meaning Vaillant ecoTec exclusive Green iQ combi boiler error codes F.00 Interruption: Flow sensor NTC plug not plugged in or has come loose, multiple plug on the PCB not plugged in correctly, interruption in cable harness, NTC defective F.01 Interruption: Return sensor F.02 Interruption: DHW outlet sensor F.03 Interruption: Cylinder sensor F.10 Short circuit: …

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Vaillant CI-SI Boiler Error Codes

Fault Codes Fault Description Possible Causes Fault Code F1 Ignition Failure Insufficient Inlet Working Gas Pressure At The Appliance Flue Problem Spark Generation Issue Incorrect Gas Valve Adjustment (Minimum Burner Pressure Set Too Low) Flame Rectification Issue Combustion Issue (Poor Flame Picture) Software Error On The Main PCB Or The User Interface PCB Fault Code F2 Air Fault Fan Fault Fan …

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Worcester Bosch Greenstar I System / Combi Boiler Error Codes

Worcester Bosch Greenstar I System / Combi Boiler Error Codes Fault Description System Behaviour 226 Service tool has been connected in the blocking error history menu FD 231 The power has been interrupted during a lockout C7 214 Fan does not run during the start up phase – fan harness connector needs checking C6 215 …

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Worcester Bosch CDi Classic Regular Boiler Error Codes

Worcester Bosch CDi Classic Regular Boiler Error Codes Fault Description System Behaviour B1 Code plug not detected C6 Fan speed too low E2 Central heating (CH) flow negative thermistor coefficient (NTC) sensor defective E9 Safety temperature limiter in central heating (CH) flow has tripped EA Flame not detected F0 Internal error F7 Flame detected even …

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Worcester Bosch  Greenstar 25/30 Si Combi Boiler Error Codes

Worcester Bosch  Greenstar 25/30 Si Combi Boiler Error Codes Fault Description System Behaviour T1 Ignition test – checking the igniter spark T2 Fan test – checking the basic fan T3 Pump test – checking the basic pump T4 Three way valve test T6 Ionisation oscillator test 9A 362 error – incorrect HCM fitted 9U 233 …

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Worcester Bosch CDI Highflow Combi Boiler Error Codes

Worcester Bosch CDI Highflow Combi Boiler Error Codes Fault Description System Behaviour A1 Pump dry run detection or pump is running in air the system pressure needs checking A5 Tank negative thermistor coefficient (NTC) defect A7 Domestic hot water (DHW) negative thermistor coefficient (NTC) defect A8 Energy Management System (EMS) communication error B1 Code plug …

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Vaillant EcoTEC Gas Boiler Diagnostic codes

Vaillant EcoTEC Gas Boiler Error Codes Fault Code Possible Cause D.0 Heating part load error D.1 Water pump overrun – time for heat mode D.2 Max burner anti-cycling period at 20c flow temperature D.3 Hot water flow temperature reading D.4 Current temperature for warm stat sensor D.5 Set value of flow temperature or target value …

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Vaillant EcoTEC Plus Gas Boiler (Program Mode Codes)

Vaillant EcoTEC Plus Gas Boiler (Program Mode Codes)   Display Meaning P.00 Bleeding test program. The heating circuit and hot water circuit (combination boiler only) is bled via the automatic air vent (the cap on the automatic air vent must be loosened). P.01 Test program where the appliance is operated in full load after successful …

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Vaillant EcoTEC Plus Regular Gas Boiler (Diagnostic Codes)

Vaillant EcoTEC Plus Regular Gas Boiler Error Codes (Diagnostic Codes) D.0 Heating part load error D.1 Water pump overrun – time for heat mode D.2 Max burner anti-cycling period at 20c flow temperature D.3 Hot water flow temperature reading D.4 Current temperature for warm stat sensor D.7 Warm start temperature target value D.8 External controls …

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Vaillant EcoTEC Plus Regular Gas Boiler Error Codes (Status Codes)

Vaillant EcoTEC Plus Regular Gas Boiler Error Codes Fault Code Possible Cause S.20 Warnstar demand S.21 Fan running S.22 Pump running S.23 Ignition sequence S.24 Burner ignited S.25 Fan and water pump running S.26 Fan overrun S.27 Pump overrun S.28 Anti-cycling mode S.30 No heating demand from external controls S.31 Central heating thermostat knob turned …

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