Low
d.51 on Vaillant ecoFIT pure

Your boiler is notifying you that it has adjusted its fan speed settings to ensure the gas and air mixture remains at the correct level for efficient operation.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Correction of the maximum 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 →

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