Low
S.0 on Vaillant ecoFIT Pure 425

Your boiler is currently in standby mode because it has not been asked to provide any heating 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

Heating mode: No requirement

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 32.
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 settings to ensure a heating schedule is active.Verify that your hot water timer is set to 'on'.Increase the target temperature on your room thermostat to see if the boiler initiates a firing sequence.

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S.1View →S.2View →S.3View →

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