Low
S.22 on Vaillant ecoTEC plus Regular

Your boiler is currently moving water through the system to prepare for heating or to cool itself down after use.

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

Hotwaterhandlingmode:Pumppre-run

From this model's manual
Verified against the Vaillant Ecotec Plus Regular 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.

What causes this fault?

This is a normal operational status rather than a fault, occurring when the boiler's internal pump circulates water around your radiators or cylinder. It most commonly happens during a 'pre-run' to ensure everything is safe before the burner ignites, or as an 'overrun' to dissipate heat after the heating has turned off.

DIY fix possible

Wait for 5-10 minutes as the boiler is likely just finishing a cycleCheck that your room thermostat is set to your desired temperatureEnsure there is water pressure in the system if you have a gauge visible

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