Low
c 1 05 on Atag A200

Your boiler is currently running an automated process to remove trapped air from the system, which is a normal self-maintenance cycle and not a breakdown.

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.

What the manual says

Manufacturer manual

7 minute de-aeration cycle begins (appears the moment the pressure exceedes 1.3 bar)

From this model's manual
Verified against the Atag A200 System installation & service manual, page 36.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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