Medium
d.75 on Vaillant ecoFIT Pure 835

Your boiler has timed out because it is taking too long to heat up your hot water cylinder to the required temperature.

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

Maximum cylinder reheating time

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.22View →F.24View →F.28View →

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