Low
d.50 on Vaillant ecoFIT Pure 425

Your boiler is displaying an internal message regarding how slowly the fan is spinning, which usually means the system is attempting to calibrate itself but may need a professional adjustment.

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.

What the manual says

Manufacturer manual

Correction of the minimum fan speed

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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F.32View →d.51View →

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