Low
S.03 on Vaillant ecoTEC Plus 826

Your boiler is currently in the process of attempting to light the burner to start heating 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: Ignition

From this model's manual
Verified against the Vaillant Ecotec Plus 826 installation & service manual, page 47.
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 successfully finishes its ignition sequence.Ensure your thermostat or timer is calling for heat.Check that your gas supply is turned on if you have recently had other gas work done.

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