Low
d.50 on Vaillant Home System

Your boiler is adjusting the lowest speed of the internal fan to ensure it runs efficiently at low power levels.

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: 0 to 3000 rpm. Fan speed=Display value x 10

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.33View →d.34View →

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