Low
S.31 on Vaillant ecoFIT Pure 830

Your boiler is currently in standby mode because it has not been asked to provide heating or hot water, often because it is set to summer mode or the room thermostat is satisfied.

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

No heating demand: Summer mode, eBUS controller, waiting period

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 the heating is turned onVerify that the boiler's mode is set to 'Winter' or 'Combi' if you require heatingIncrease the desired room temperature on your thermostat to see if the boiler initiates a firing sequence

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S.30View →S.32View →

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