Low
S.01 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently preparing to provide heating and is going through its normal start-up sequence.

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 Ecotec Plus Aquaplus 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

No action is required as this is a status message rather than a fault.Ensure your thermostat is calling for heat.Wait a few minutes for the boiler to complete its cycle and begin heating your radiators.

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Related fault codes

S.02View →S.03View →S.04View →

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