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.

Technical description

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

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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Related fault codes

F.22View →F.24View →

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