What the manual says
Manufacturer manualPrimary operating mode (0: Programming, 1: Manual, 2: Antifreeze/Holiday)
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
Locate the mode selector or dial on the front control panel.Switch the setting from 'Programming' or 'Holiday' back to the 'Winter' or 'Summer' operating position.Check if the display returns to normal and the boiler fires up.
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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.02.55AM001AM010AM011AM012AM014AM015AM016AM018AM019AM024AM027AM036AM037AM040AM091AM101AP073AP079BM000CM030CM120CM190CM210CM280CP000CP020CP210CP230CP470CP480CP490CP780DM001DM002DM005DM019DM029DP430DP440E.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