Low
S.10 on Vaillant Home System

Your boiler is currently working correctly and is simply indicating that it has received a signal to start heating up your hot water cylinder.

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

Hot water handling mode: Requirement

DIY fix possible

No action is required as this is a normal status message rather than a fault code.Wait for the boiler to finish the heating cycle, after which the code will change.Ensure your hot water cylinder thermostat is set to your preferred temperature.

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Related fault codes

S.20View →S.24View →

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