Low
S.25 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently cooling down its internal components after heating up your hot water tank.

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 and water pump over run (store charging)

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 normal operational status message, not a fault.Wait for the 'S' code to disappear once the cooling cycle finishes.Ensure your room thermostat is calling for heat if you want the radiators to come on next.

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