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.

Technical description

Fan running (heating operation)

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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Related fault codes

S.02View →S.03View →S.04View →

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