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

Shared across the 400 Combi 2 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

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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All 110 fault codes on the 400 Combi 2

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

A.00 .28A.00 .29A.00.34A.02 .37A.02 .45A.02 .46A.02 .48A.02 .49A.02 .54A.02 .76A.02.06A.02.36A.02.55AM001AM010AM011AM012AM014AM015AM016AM018AM019AM024AM027AM036AM037AM040AM091AM101AP073AP079BM000CM120CM190CM210CM280CP000CP020CP210CP230CP470CP480CP490CP780DM001DM002DM005DM009DM019DM029DP430DP440E.00.04E.00.05E.00.16E.00.17E.00.20E.00.21E.01.04E.01.12E.01.17E.01.20E.02 .13E.02 .35E.02 .39E.02 .47E.02.17E.04 .29E.04 .54E.04.01E.04.02E.04.03E.04.08E.04.10E.04.12E.04.13E.04.17E.04.18E.04.23GM001GM002GM003GM004GM007GM008GM012GM013GM044H.00 .81H.00.42H.01.00H.01.05H.01.08H.01.14H.01.18H.01.21H.02 .70H.02.00H.02.02H.02.03H.02.04H.02.05H.02.07H.02.09H.02.10H.03 .54H.03.00H.03.02H.03.05

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