High
F.29 on Vaillant ecoTEC plus Regular

Your boiler is trying to stay lit but failing, which means it has stopped producing heat and hot water as a safety precaution.

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

Failure during operation: Re-ignition unsuccessful

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.28View →F.27View →

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