Low
D.22 on Vaillant Turbomax Plus

Your boiler is simply letting you know that you have turned on a hot water tap and it is preparing to heat the water for you.

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 Turbomax Plus installation & service manual, page 39.
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

This is not an error code, but a status notification.No action is required as the boiler is operating exactly as it should.If your water is not getting hot despite this code, check that your tap is fully open and the water pressure is sufficient.

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D.21View →D.23View →

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