Low
d.66 on Vaillant ecoFIT Pure 830

Your boiler is simply letting you know that the 'warm start' feature is currently active, which keeps a small amount of water pre-heated so you get hot water faster when you turn the tap on.

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.

What the manual says

Manufacturer manual

Activation of the warm start function for hot water

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

This is a status message, not a fault, so no repair is required.If you wish to turn this feature off to save energy, navigate to the hot water settings on your boiler display.Locate the 'Warmstart' or 'Comfort' mode setting and select 'Off'.

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