BoilerFaultCodesBaxi 40 Fault Code
The Baxi 40 fault code means: your boiler has detected that it is not firing up correctly, usually because the pilot light has gone out or there is an issue with the ignition process.. It appears on 26 Baxi models in our database.
Technical description: 11.72kW (40,000 Btu/h)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A cover plan would handle faults like 40: no call-out fees, no surprise bills.
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Baxi models that show the 40 fault code
Click a model for the full fault code list and model-specific repair notes.
- 124 Combi Repair: £90-160
- 200 / 400 Combi Repair: £120-200
- 600 Combi (range) Repair: £90-160
- 624 Combi Repair: £90-160
- 630 COMBI LPG
- 636 COMBI
- 636 COMBI LPG
- 825 Combi Repair: £90-160
- Assure Repair: £150-300
- Bahama 100 Repair: £150-300
- Combi Instant 80/105 HE Repair: £120-220
- Duo-tec Combi GA Repair: £90-160
- Duo-tec Combi HE A Repair: £120-200
- EcoBlue Repair: £120-200
- Ecoblue 12 System ErP
- Ecoblue 15 System ErP
- Ecoblue 24 System ErP
- Ecoblue 28 System ErP
- Ecoblue Advance Combi Repair: £120-220
- EcoBlue System Repair: £120-200
- Ecoblue18 System ErP
- PLATINUM COMPACT 25 COMBI
- PLATINUM COMPACT 30 COMBI
- PLATINUM COMPACT 36 COMBI
- Solo 3 Repair: £120-250
- Solo 3 PFL Repair: £150-300
Source
Baxi 40 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