Low
d.50 on Vaillant ecoFIT Pure 435

Your boiler is notifying you that it has automatically adjusted the fan's minimum power level to ensure the system continues to run reliably.

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 minimum 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 →d.51View →

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