Low
D.50 on Vaillant Atmomax

Your boiler is providing a diagnostic message about an internal fan speed setting rather than a breakdown code, often appearing during initial setup or after maintenance.

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

Offset for minimum 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.51View →F.32View →

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