Medium
d.75 on Vaillant ecoFIT pure

Your boiler has taken longer than expected to heat up your hot water tank, so it has timed out for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

DIY fix possible

Check that your hot water cylinder thermostat is not set to an unusually high temperatureEnsure all valves on the pipework leading to your hot water tank are fully openRestart the boiler to see if the message clears and heating resumes

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Related fault codes

F.22View →F.24View →

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