Medium
d.40 on Vaillant ecoFIT Pure 412

Your boiler is reporting an issue with the temperature of the water currently flowing through your heating system, often caused by a sensor reading or a circulation problem.

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

Heating flow temperature

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.20View →F.22View →d.41View →

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