Medium
S.46 on Vaillant Atmomax

Your boiler is struggling to maintain a steady flame when running at its lowest power setting, which may cause it to stop working unexpectedly.

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

Comfort safety mode flame loss at minimum load

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.28View →F.29View →S.41View →

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