Low
S.01 on Vaillant Turbomax Plus 828

Your boiler is currently preparing its internal fan to start the heating process and this is a normal status message rather than an actual error.

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

Fan running (heating operation)

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 38.
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 that your room thermostat or programmer is calling for heatWait 2-3 minutes to see if the status changes to a heating sequenceEnsure there is a demand for heating and that radiator valves are open

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