Venting Low

Viessmann Venting Fault Code

Also written as VENTING — same fault.

The Viessmann Venting fault code means: your boiler is currently running a routine automated process to clear trapped air from its internal system.. It appears on 5 Viessmann models in our database.

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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Viessmann models that show the Venting fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Viessmann Venting fault code information on this page is sourced and cross-checked against the official Viessmann service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026