BoilerFaultCodesBaxi 109 Fault Code
The Baxi 109 fault code means: your boiler is struggling to move water around the system properly before it starts the main heating process, usually due to a blockage or a pump issue.. It appears on 10 Baxi models in our database.
Technical description: Pre-circulation fault
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 109 fault code
Click a model for the full fault code list and model-specific repair notes.
- 124 Combi Repair: £150-£350
- 200 / 400 Combi Repair: £150-300
- 600 Combi (range) Repair: £150-£350
- 624 Combi Repair: £150-£350
- EcoBlue Repair: £150-300
- Ecoblue Advance Combi Repair: £150-300
- EcoBlue Advance Heat Repair: £150-£350
- EcoBlue Heat Repair: £150-300
- EcoBlue Plus Combi Repair: £150-£350
- EcoBlue System Repair: £150-350
Source
Baxi 109 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