Low
S.24 on Vaillant ecoTEC plus Regular

Your boiler is currently firing up and heating normally; this is a status update rather than a fault code.

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

DHWmode:Burneron

From this model's manual
Verified against the Vaillant Ecotec Plus Regular installation & service manual, page 32.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This status occurs when the boiler has successfully completed its ignition sequence and the burner is now actively heating your water. It is a sign that the internal gas valve has opened and the spark electrode has ignited the fuel to provide heat for your radiators or hot water tank. This is part of the boiler's normal operation and indicates the system is working exactly as it should.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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