Baxi Boiler On light Fault Code
Also written as BOILERONLIGHT — same fault.
The Baxi Boiler On light fault code means: your boiler is working normally and is currently receiving a signal to provide heating or hot water.. It appears on 2 Baxi models in our database.
Technical description: Indicates boiler is operational or calling for heat
DIY fix possible
Check your room thermostat is set to the desired temperatureEnsure your programmer or timer is set to an 'on' periodNo action is required if your radiators or water are heating up as expected
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Gas Safe Register →Baxi models that show the Boiler On light fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi Boiler On light 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 27 April 2026