Low
180 on Atag iS System

Your boiler is simply finishing a standard maintenance test and is returning to its normal operating mode.

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

No error — briefly visible when leaving chimney sweep function

Shared across the iS System range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 up to 2 minutes for the code to disappear automaticallyEnsure no buttons are being held downCheck that the display returns to showing the temperature or 'OK' status

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All 18 fault codes on the iS System

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

102040506178105110111117118119129133151154181

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