BoilerFaultCodesBaxi CM120 Fault Code
The Baxi CM120 fault code means: this code is simply an information message indicating the current status of your heating timer or thermostat settings, not a system fault.. It appears on 1 Baxi model in our database.
Technical description: Current operating mode in the zone (0: Scheduling, 1: Manual, 2: OFF (antifreeze), 3: Temporary)
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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Baxi models that show the CM120 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi CM120 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026