Low
D.22 on Vaillant Combi Compact 242EB

Your boiler is simply indicating that it is currently processing a request for hot water.

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 that your hot water taps are fully closedMonitor the display to see if the code changes once the tap is turned offEnsure there are no dripping taps or leaks in your hot water pipework

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