Low
S.109 on Vaillant ecoFIT Pure 418

Your boiler has entered a temporary sleep mode and is simply waiting for a signal from your heating controls to turn back 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

Product's standby mode activated

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 33.
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

Check your room thermostat or programmer to ensure it is set to 'ON' and calling for heatTurn the temperature dial on the front of the boiler up to ensure it is not set to offWait a few minutes to see if the boiler restarts automatically once the controls signal a demand for heat

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Related fault codes

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