BoilerFaultCodesBaxi 135 Fault Code
The Baxi 135 fault code means: your boiler has lost its connection to the gas supply or cannot detect the gas it needs to ignite, which has caused it to shut down for safety.. It appears on 16 Baxi models in our database.
Technical description: Interruption Of Gas Supply (Internal Error)
DIY fix possible
Check if other gas appliances in your home, such as a gas hob, are still working correctly.Ensure your gas meter has credit and the emergency control valve is in the 'on' position.Attempt to reset the boiler by following the reset procedure in your user manual.
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A cover plan would handle faults like 135: no call-out fees, no surprise bills.
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Baxi models that show the 135 fault code
Click a model for the full fault code list and model-specific repair notes.
- 124 Combi Repair: £120-350
- 128 Combi Repair: £120-350
- 615 System 15 Repair: £90-250
- 618 SYSTEM Repair: £90-250
- 624 System 24 Repair: £90-250
- 818 System Repair: £150-380
- 824 SYSTEM Repair: £150-380
- Assure Repair: £120-250
- Combi Instant 80/105 HE Repair: £120-250
- Duo-tec Combi GA Repair: £150-£350
- 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 135 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