Baxi SF Fault Code
The Baxi SF fault code means: your boiler is currently running a brief self-diagnostic calibration test, which is a normal process after recent adjustments or a power cycle.. It appears on 1 Baxi model in our database.
Technical description: Calibration Mode active (alternating with current boiler temperature)
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 SF fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi SF 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