Low
d.50 on Vaillant ecoFIT Pure 418

Your boiler's computer is making small internal adjustments to how the fan runs to ensure it stays efficient and safe.

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.

DIY fix possible

No action is required as this is an automatic internal calibration.Monitor the boiler to see if the code clears itself after a short period.If the code persists and prevents the boiler from firing, try a simple reset.

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