Low
S.03 on Vaillant ecoFIT Pure 835

Your boiler is currently in the process of attempting to light the flame to heat your home.

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: Burner ignition

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

Wait a few minutes to see if the boiler completes the startup process automaticallyCheck that your external heating controls, such as your room thermostat, are set to 'On' and calling for heatEnsure your gas supply is active and that other gas appliances in the home are working correctly

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