Low
S.14 on Vaillant ecoTEC exclusive Combi

Your boiler is operating normally and is currently heating up water for your taps or shower.

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: Burner on

From this model's manual
Verified against the Vaillant Ecotec Exclusive Combi installation & service manual, page 41.
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 code appears when the boiler's internal burner has successfully ignited and is currently generating heat for your radiators or hot water. It is not a fault, but rather a status message indicating that the system is working exactly as intended. You will see this whenever the thermostat or a hot tap calls for energy.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.13View →S.15View →

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