Low
d.31 on Vaillant ecoFIT Pure 425

Your boiler is currently telling you how it is set to refill its water pressure, rather than indicating a breakdown or a dangerous fault.

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 or 'i' button to exit the diagnostic modeIf you want to change the filling mode, refer to the user manual to toggle between 0, 1, or 2Monitor your water pressure gauge to ensure it stays between 1.0 and 1.5 bar

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