Low
d.66 on Vaillant ecoFIT Pure 412

Your boiler is simply indicating that the 'warm start' feature is currently active, which keeps a small amount of water pre-heated so your hot water arrives at the tap more quickly.

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

Activation of the warm start function for hot water

DIY fix possible

This is a status message, not a fault code.If you wish to save energy, access the boiler menu.Locate the 'Warmstart' setting and switch it to 'Off'.

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