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Worcester Bosch Boiler Fault Codes
Browse the available Worcester Bosch boiler fault codes in one place, then open the exact code page for the documented meaning, evidence limits and safe next steps.
Definitions can vary by model and region. Some codes remain unconfirmed; check the complete display, exact model and the page's sources before taking action.
Browse the parent brand page: Worcester Bosch or compare across brands in the boiler codes across brands.
Fault codes
26
Code categories
11
Guides linked below
0
Code pages to start with
Browse code categories
Operating-status displays
6 pages in this category. Open 200 as one example and check its model limits.
sensor codes
4 pages in this category. Open 101 as one example and check its model limits.
Codes awaiting confirmation
4 pages in this category. Open 110 as one example and check its model limits.
overheat codes
3 pages in this category. Open 224 as one example and check its model limits.
circulation codes
2 pages in this category. Open 281 as one example and check its model limits.
ignition codes
2 pages in this category. Open 227 as one example and check its model limits.
Code categories in this library
Counts refer to published code pages, not how often an appliance develops a fault.
operating status (6)
sensor (4)
unconfirmed (4)
overheat (3)
circulation (2)
ignition (2)
More code pages
110: model confirmation needed
Meaning unconfirmed; exact model documentation is required
200: operating status
Heating mode
201: operating status
Hot-water mode
202: operating status
Anti-cycle mode
204: operating status
Boiler water above the target temperature
208: operating status
Chimney-sweep demand
268: operating status
Relay test activated
101 meaning and guidance
Collector T1 sensor lead short circuit with controller Fault 40
102 meaning and guidance
Collector T1 sensor lead break with controller Fault 40
104 meaning and guidance
Solar-cylinder T2 sensor lead break with controller Fault 41
224 meaning and guidance
Flue-gas or heat-exchanger temperature limiter activated
227 meaning and guidance
No flame signal after ignition
All fault codes in this cluster
26 code pages currently available for this brand and appliance. A severity label does not establish whether an appliance is safe to use.
| Code | Meaning | Issue type | Severity |
|---|---|---|---|
| 101 | Collector T1 sensor lead short circuit with controller Fault 40 | sensor | Not assessed |
| 102 | Collector T1 sensor lead break with controller Fault 40 | sensor | Not assessed |
| 104 | Solar-cylinder T2 sensor lead break with controller Fault 41 | sensor | Not assessed |
| 110 | Meaning unconfirmed; exact model documentation is required | unconfirmed | Not established |
| 200 | Heating mode | operating status | Operating status |
| 201 | Hot-water mode | operating status | Operating status |
| 202 | Anti-cycle mode | operating status | Operating status |
| 204 | Boiler water above the target temperature | operating status | Operating status |
| 208 | Chimney-sweep demand | operating status | Operating status |
| 224 | Flue-gas or heat-exchanger temperature limiter activated | overheat | Not assessed |
| 227 | No flame signal after ignition | ignition | Not assessed |
| 229 | Flame failed during burner operation | flame loss | Not assessed |
| 232 | Boiler blocked by an external switching contact | power control | Not assessed |
| 233 | Boiler identification module or electronics fault | pcb control | Not assessed |
| 268 | Relay test activated | operating status | Operating status |
| 281 | Pump stuck or running in air | circulation | Not assessed |
| 286 | Return temperature too high when paired with D1 | overheat | Not assessed |
| 295 | Meaning unconfirmed; exact model evidence required | unconfirmed | Not established |
| 296 | Meaning unconfirmed; exact model evidence required | unconfirmed | Not established |
| 297 | Meaning unconfirmed; exact model evidence required | unconfirmed | Not established |
| A1 | Pump stuck or running in air when paired with 281 | circulation | Not assessed |
| C6 | Fan speed too high (215) or too low (216) | fan flue | Not assessed |
| CE | Low pressure (207) or no pump-start pressure variation (266) | pressure level | Not assessed |
| D1 | Return sensor or return-temperature fault; cause code required | sensor | Not assessed |
| E9 | Temperature safety or related protection fault; cause code required | overheat | Not assessed |
| EA | Ignition or flame-monitoring fault; cause code required | ignition | Not assessed |