Low
S.14 on Vaillant Thermocompact

Your boiler is operating normally and is currently in the process of firing up to provide heat or 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

Burner ignited (hot water operation)

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.

What causes this fault?

This is a normal operational status and does not indicate a breakdown or a malfunction. It occurs when the boiler has successfully confirmed the presence of a flame and is currently burning gas to heat your home or water. You will see this code every time the boiler starts up correctly and begins its heating cycle.

DIY fix possible

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

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