Low
d.43 on Vaillant ecoFIT Pure 412

Your boiler is simply showing you a setting related to how it calculates the water temperature needed to heat your home based on the outside temperature.

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

Heating curve

Engineer required

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

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Related fault codes

d.45View →

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