BoilerFaultCodesBaxi 15 Fault Code
The Baxi 15 fault code means: your boiler has detected an issue with the system that controls the flow of gas, meaning it cannot ignite or stay running to provide heating and hot water.. It appears on 15 Baxi models in our database.
Technical description: Gas Valve 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 15 fault code
Click a model for the full fault code list and model-specific repair notes.
- 124 Combi Repair: £250-450
- 600 Combi (range) Repair: £220-380
- 624 Combi Repair: £120-£280
- 825 Combi Repair: £250-£450
- Assure
- Bahama 100 Repair: £150-300
- Bahama 80e / 105e
- Combi 80 Maxflue
- Combi 80e
- Combi Elite
- Combi Instant 80/105 HE Repair: £250-450
- Duo-tec Combi GA Repair: £180-350
- Duo-tec Combi HE A Repair: £180-350
- EcoBlue Heat Repair: £0-80
- EcoBlue System Repair: £120-250
Source
Baxi 15 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