Low
d.31 on Vaillant ecoFIT pure

Your boiler is notifying you of its current setting for filling itself with water, which is an status update 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.

Technical description

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

DIY fix possible

No action is usually required as this is an information code.If you wish to change how the boiler fills, consult the user manual to toggle between manual and automatic modes.Check your water pressure gauge to ensure it is between 1.0 and 1.5 bar.

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