Low
S.24 on Vaillant Turbomax Plus 828

Your boiler is briefly firing up to pre-heat its internal water supply so that you get hot water more quickly when you turn the tap on.

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

Burner ignited (warm start)

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 38.
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

Locate the right-hand control knob on the boiler fasciaTurn the knob fully anticlockwise to the 'Off' position to disable the pre-heat featureObserve if the 'S.24' code disappears and only returns when hot water is requested

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