High
F.20 on Vaillant ecoTEC Plus 610

Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Safetyswitch-off:Overheatingtemperaturereached | Incorrectearthconnectionbetweencableharnessandproduct,floworreturnNTCdefective(looseconnection),blackdischargeviaignitioncable,ignitionplugorignitionelectrode

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.23View →F.24View →

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