BoilerFaultCodesBaxi 4 flashes red Fault Code
Also written as 4FLASHESRED — same fault.
The Baxi 4 flashes red fault code means: your boiler's fan, which safely pushes exhaust gases out of the flue, is not spinning at the correct speed or has stopped working entirely.. It appears on 4 Baxi models in our database.
Technical description: Fan fault: Fan calibration error, Fan failure
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Baxi models that show the 4 flashes red fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi 4 flashes red fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
- Baxi 613 Heat manual (PDF)
- Baxi 800 Heat (range) manual (PDF)
- Baxi EcoBlue Advance Heat manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026