Low
D.22 on Vaillant Atmomax

Your boiler is letting you know that a hot water tap is currently turned on or being requested.

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

Hot water demand

DIY fix possible

Check all hot water taps in the property are fully closedEnsure any mixer showers are turned off completelyCheck for any leaking hot water pipes or dripping taps

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