High
F.29 on Vaillant ecoTEC Pro 30

Your boiler is trying to stay lit but keeps failing, which means it has stopped providing heating and hot water for safety reasons.

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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