Low
d.22 on Vaillant ecoTEC plus aquaPLUS

Your boiler has detected that a hot water tap is currently turned on or there is a demand 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.

What the manual says

Manufacturer manual

Domestic hot water demand

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual.
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

Check all hot water taps are fully closedEnsure any showers or mixer taps are not leaking or drippingWait for the boiler to finish providing hot water, as this is a status code rather than a fault

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