10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Worcester Bosch Greenstar 30Ri
The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 41-019-11 | 330+ | 2008–present |
Tap any card for details
Your boiler has detected that the internal component responsible for clearing exhaust gases is not operating correctly, so it has safely shut down to prevent any unsafe buildup.
Your boiler is lighting up, but the flame is cutting out shortly after, meaning your heating and hot water will not stay on.
Your boiler has detected that it is running too hot and has automatically switched itself off to prevent any damage.
Your boiler is struggling to read the temperature of the water flowing to your radiators, so it has turned itself off to prevent overheating.
Your boiler's internal sensor that monitors the water temperature returning from your radiators has lost its connection, causing the system to stop heating to prevent damage.
Your boiler's temperature sensor is sending conflicting information, causing the system to stop working as a precaution to prevent overheating.
Your boiler's main control computer is having a memory or communication error, which prevents it from safely operating your heating and hot water.
Your boiler has detected an issue with the internal component that controls the flow of gas, meaning it cannot safely ignite to provide heating or hot water.
Your boiler is having a communication breakdown with its internal controls, meaning it cannot receive signals to provide heating or hot water.
Your boiler has lost communication with its external controls or internal wiring kit, preventing it from heating your home.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes