BoilerFaultCodesBaxi 15 Fault Code
The Baxi 15 fault code means: your boiler has detected a problem with the temperature sensor on the central heating system, so it has temporarily stopped working to prevent overheating.. It appears on 23 Baxi models in our database.
Technical description: Central Heating NTC 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
- 128 Combi Repair: £250-450
- 615 System 15 Repair: £150-350
- 618 SYSTEM Repair: £150-350
- 624 System 24 Repair: £150-350
- 818 System Repair: £100-£200
- 824 SYSTEM Repair: £100-£200
- 825 Combi Repair: £250-£450
- 830 COMBI Repair: £250-£450
- 836 COMBI Repair: £250-£450
- Assure
- Bahama 100 Repair: £150-300
- Bahama 80e / 105e
- Combi 80 Maxflue
- Combi Instant 80/105 HE Repair: £250-450
- Duo-tec Combi GA Repair: £180-350
- EcoBlue System Repair: £120-250
- Neta-tec Combi 24 GA
- Neta-tec Combi 28 GA
- Neta-tec Combi 33 GA
- PLATINUM COMPACT 25 COMBI Repair: £100-250
- PLATINUM COMPACT 30 COMBI Repair: £100-250
- PLATINUM COMPACT 36 COMBI Repair: £100-250
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 31 August 2026