Low
S.109 on Vaillant ecoFIT Pure 825

Your boiler is currently in a temporary standby state and is not actively heating, often because the system has been switched off at the controls or is waiting for a signal from your thermostat.

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 smart controller to ensure it is calling for heatEnsure the boiler's on/off switch on the front panel is set to the 'on' positionCheck that your heating timer or programmer is currently set to an 'on' period

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