Low
105 on Atag iR15

Your boiler is currently running a brief internal safety check to clear out trapped air after the electricity was recently interrupted or 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 (runs approx. 7 mins.)

From this model's manual
Verified against the Atag/Atag Ir Regular 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 for approximately 7 minutes for the automatic venting program to finish running.Do not turn off or reset the boiler while this cycle is in progress.Once the timer completes, the boiler should return to normal operation automatically.

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All 15 fault codes on the iR15

Seeing a different code? Every code this model can display, in one place.

1020405061110111119129133151154180181

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