Low
02 on Baxi EcoBlue System

Your boiler is having trouble communicating with the outdoor sensor that measures the air temperature, which may affect how efficiently your heating responds to weather changes.

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

alternates with Outside Temperature (where Sensor fitted)

From this model's manual
Verified against the Baxi Ecoblue 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.

Engineer required

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

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