Low
d.31 on Vaillant ecoFIT Pure 418

Your boiler is currently set to a specific mode for how it refills with water, and this code is simply an information setting rather than a breakdown.

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

Automatic filling device (0=Manual, 1=Semi-automatic, 2=Automatic)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
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

Press the 'Menu' button on the control panelUse the arrow keys to navigate to the 'Live Monitor' or 'Diagnostic' settingsIdentify if the setting matches your preferred filling method (usually manual for most UK homes)

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