Low
105 on Atag iR Regular

Your boiler is currently running an automatic air-purging sequence to clear air from the system following a power cut or being switched back on.

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

Venting program active when power turned on or interrupted

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

DIY fix possible

Wait approximately 7 to 10 minutes for the automatic venting process to complete.Check that your radiators are bled and the system pressure is between 1.0 and 1.5 bar.Ensure the boiler power supply is stable and not being interrupted by a loose plug or tripped fuse.

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