Low
D.7 on Vaillant Atmomax

Your boiler is displaying an information code rather than a fault, indicating the current target temperature for the pre-heated hot water function.

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

Warm start temperature target value

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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

Check if the 'Warm Start' feature (pre-heat) is turned on via the right-hand control knob.Adjust the hot water temperature dial to your preferred setting.If you wish to save energy, turn the hot water dial fully left until it clicks to disable this feature.

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