High
S.13 on Vaillant Turbomax Plus 824/828E

Your boiler is currently trying to light the flame to heat your water, but it has not yet confirmed that the flame has successfully started.

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

Ignition sequence (hot water operation)

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.29View →

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