Baxi Fan On Fault Code
Also written as FANON — same fault.
The Baxi Fan On fault code means: your boiler is operating normally, and this indicator light simply shows that the internal fan is running as expected to vent the system.. It appears on 3 Baxi models in our database.
Technical description: Indicator light - Check if fan and pressure switch plug is connected and if there is mains at the fan connection
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Baxi models that show the Fan On fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi Fan On 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