Low
d.31 on Vaillant ecoFIT Pure 412

Your boiler is simply displaying a setting configuration for its internal water-refilling feature rather than indicating a breakdown or 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)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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