High
F.29 on Vaillant ecoTEC Plus 826

Your boiler has stopped because the flame inside has gone out and it is unable to restart itself.

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

Ignitionandcheckfaults duringoperation–flamehas goneout

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.27View →F.28View →

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