Medium
d.50 on Vaillant ecoFIT Pure 835

Your boiler is warning you that its internal fan is struggling to run at the necessary low speed required for efficient and safe operation.

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

Correction of the minimum fan speed

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 →d.51View →

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