Low
d.51 on Vaillant ecoFIT Pure 425

Your boiler is adjusting its fan power settings to maintain a safe and stable flame.

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

d.50View →F.32View →

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