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.

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

Warm start temperature target value

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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