Low
d.22 on Vaillant ecoMAX

Your boiler is simply showing that it has received a request to provide hot water to your taps or shower.

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

Domestic hot water demand

From this model's manual
Verified against the Vaillant Ecomax installation & service manual, page 47.
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

No action is required as this is a normal operating status codeCheck your hot water taps to ensure they are fully closedObserve if the boiler proceeds to heat water as expected

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d.22View →d.23View →

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