Low
Venting on Viessmann Vitodens 100-W / 200-W

Your boiler is currently running a routine automated process to clear trapped air from its internal system.

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

Whilst venting is in progress (weather-compensated control unit)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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