BoilerFaultCodesWhat the manual says
Manufacturer manualCurrent operating mode in the zone (0: Scheduling, 1: Manual, 2: OFF (antifreeze), 3: Temporary)
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.
DIY fix possible
Check your external thermostat or boiler controller settingsAdjust your heating schedule or mode if you wish to change how the boiler is currently operatingPress the reset button only if the boiler has stopped working, though this code should not require a reset
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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.02.55AM001AM010AM011AM012AM014AM015AM016AM018AM019AM024AM027AM036AM037AM040AM091AM101AP073AP079BM000CM030CM190CM210CM280CP000CP020CP210CP230CP470CP480CP490CP780DM001DM002DM005DM009DM019DM029DP430DP440E.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