Medium
d.75 on Vaillant ecoFIT Pure 412

Your boiler has stopped trying to heat your hot water tank because it has taken too long to reach the desired temperature, likely due to a system efficiency issue or a blockage.

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.75View →d.77View →

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