Low
d.45 on Vaillant ecoFIT Pure 412

Your boiler is displaying a background setting related to how it calculates the water temperature, but this is an information display for an engineer rather than a functional 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

Value for the base point of the heating curve

Engineer required

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

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