Low
CM210 on Baxi 400 Combi 2

Your boiler is simply displaying the current temperature from an outdoor sensor and is not indicating a fault with your heating system.

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 in the zone °C

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 56.
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

Check your boiler control panel display settings.Press the reset or back button to return to the main home screen.Refer to your user manual to toggle the display view if you prefer to see time or pressure instead of the outdoor temperature.

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