Low
S.11 on Vaillant Home System

Your boiler is currently preparing itself for a hot water demand by clearing the internal combustion chamber with the fan.

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: Advance fan operation

DIY fix possible

Check if your hot water timer or thermostat is activeMonitor the display to see if it changes to a heating or hot water code (starting with S.2 or S.4)No action is required as this is a normal operational status message, not a fault

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Related fault codes

S.10View →S.14View →S.24View →

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