Low
CM030 on Baxi 400 Combi 2

This code is simply displaying the current temperature inside your home rather than indicating a fault with your boiler.

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

Current room temperature for 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 thermostat or boiler control panel settingsPress the back or menu button to return to the standard display modeConsult your user manual to adjust the display preferences

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