Low
d.31 on Vaillant ecoFIT Pure 835

Your boiler is notifying you of its current automatic filling system setting rather than indicating a breakdown or safety failure.

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

Identify if you want the boiler to top itself up or if you prefer to do it manuallyAccess the installer level menu (code 96) to adjust the setting if desiredPress the 'Back' or 'Menu' button to clear the status display

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Related fault codes

F.22View →F.24View →

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