BoilerFaultCodesWorcester Bosch LOCKOUT Fault Code
The Worcester Bosch LOCKOUT fault code means: your boiler has stopped working because it failed to light or stay lit, and it needs a professional to investigate why it cannot maintain a stable flame.. It appears on 15 Worcester Bosch models in our database.
Technical description: General burner lockout condition requiring investigation of pulsation, electrical connections, flame detection, or fuel supply
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 LOCKOUT: no call-out fees, no surprise bills.
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Worcester Bosch models that show the LOCKOUT fault code
Click a model for the full fault code list and model-specific repair notes.
- 24CDi BF Repair: £150-300
- 24si II Repair: £150-350
- 26 CDi Xtra Repair: £120-250
- 28i Junior Repair: £180-350
- 28i RSF Repair: £180-350
- Greenstar 12i System Repair: £150-300
- Greenstar 15i System Repair: £150-350
- Greenstar 2000 Repair: £120-250
- Greenstar 25Si Repair: £150-300
- Greenstar 27CDi Repair: £120-250
- Greenstar 28CDi Repair: £120-250
- Greenstar 30si Repair: £120-250
- Greenstar Camray Utility Repair: £120-300
- Greenstar Utility Repair: £120-300
- Utility Repair: £120-300
Source
Worcester Bosch LOCKOUT fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
- Worcester Bosch 24CDi BF manual (PDF)
- Worcester Bosch 24si II manual (PDF)
- Worcester Bosch 26 CDi Xtra manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026