Low
S.108 on Vaillant Home System

Your boiler is briefly clearing out the air inside to ensure a safe burn before it starts the heating process.

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

Purging the combustion chamber, fan in operation

DIY fix possible

Wait for up to 15 minutes as this is a normal part of the boiler's startup routineCheck if the display changes to a different code after the fan stopsEnsure there is credit on your gas meter if you have a prepay system

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S.04View →

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