Low
d.05 on Vaillant ecoFIT Pure 412

This code is not a fault; it is simply a status message indicating the boiler is calculating the water temperature required to heat your home.

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

Determined heating flow set target temperature

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.00View →d.01View →

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