Medium
S.26 on Vaillant Atmomax

Your boiler is staying in a cooling-down phase for the hot water system because it thinks the fan or air pressure sensor has not switched off yet.

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

DHW mode – fan overrun

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.32View →

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