Low
D.25 on Vaillant Atmomax

Your boiler is currently heating your hot water because it has received a signal from your external thermostat or controller.

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

Hot water activation via ebus control

DIY fix possible

Check your thermostat settings to see if hot water is scheduled to be onLower the hot water temperature on your external control to see if the code disappearsNo action is required if your hot water is working as intended

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