Low
c 1 05 on Atag S 25CR

Your boiler is currently running an automatic air-purging cycle to remove trapped air from the 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

Venting program active

Engineer required

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

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