BoilerFaultCodesWhat the manual says
Manufacturer manualNo water hardness
Shared across the 800 System 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 if your external water softener is turned on and has saltPress the 'Reset' button on the front of the boilerConsult your water softener manual to ensure the communication cable is plugged into the boiler link
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Related fault codes
All 75 fault codes on the 800 System 2
Seeing a different code? Every code this model can display, in one place.
254A.00.34A.02.06A.02.18A.02.36A.02.37A.02.45A.02.46A.02.48A.02.49A.02.54A.02.55A.02.76E.00 .04E.00 .05E.00 .06E.00 .07E.00 .16E.00 .17E.00.20E.00.21E.01.04E.01.12E.01.17E.01.20E.02.13E.02.15E.02.17E.02.35E.02.47E.04.00E.04.01E.04.02E.04.03E.04.07E.04.08E.04.09E.04.10E.04.11E.04.12E.04.13E.04.14E.04.15E.04.17E.04.18E.04.19E.04.20E.04.21E.04.23E.04.24E.04.54H.00.42H.01 .00H.01 .05H.01 .08H.01 .14H.01 .18H.01 .21H.02 .00H.02 .02H.02 .03H.02 .04H.02 .05H.02 .07H.02 .09H.02 .10H.02 .12H.02 .70H.03 .00H.03 .01H.03 .02H.03 .05H.03 .17H.03 .54