Low
02 on Baxi 124 Combi

Your boiler is struggling to read the outdoor temperature, which may cause it to run less efficiently or use the wrong settings for the weather.

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

Outside Temperature (where Sensor fitted)

From this model's manual
Verified against the Baxi 124 Combi Combi 2 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.

Engineer required

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

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