Low
S.15 on Vaillant aquaPLUS

Your boiler is briefly continuing to run the fan and pump after you have finished using hot water to safely cool down the internal components.

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 and water pump over run (hot water operation)

DIY fix possible

No action is required as this is a normal operating status and not a fault.Wait for the 'S' code to disappear once the cooling cycle is complete.Ensure your taps are fully turned off.

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Related fault codes

S.05View →S.14View →S.25View →

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