Medium
S.57 on Vaillant Atmomax

Your boiler is temporarily pausing operation because it has detected a potential issue with the burner flame not settling properly during its warm-up phase.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Waiting period comfort safety mode

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.27View →F.28View →F.29View →

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