Low Information
S.22 on Vaillant ecoTEC Plus 836

Your boiler is not broken; it is simply performing a routine preparation step to ensure everything is ready before it begins heating your water.

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

Hotwaterhandlingmode:Pumppre-run

What causes this fault?

This status code appears when the boiler is getting ready to provide hot water. It activates the internal pump for a few moments to ensure there is proper water circulation before the burner fires up. This is a standard safety and efficiency check rather than a mechanical failure.

DIY fix possible

No action is required.Wait approximately 60 seconds for the boiler to complete its cycle and start providing hot water.

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Related fault codes

S.20View →S.24View →

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