Low
A xx on Atag Q 25S

Your boiler is currently performing a routine 17-minute process to safely remove trapped air from the system, so no action is required on your part.

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

Automatic de-aeration/venting programm in progress (takes 17 minutes).

Engineer required

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

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