9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 |
|---|---|---|
| 41-467-11 | System 24 Eco | 2008–2012 |
| 41-467-12 | System 28 Eco | 2008–2012 |
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Your boiler has stopped heating because it is unable to accurately measure the temperature of the water circulating through your radiators.
Your boiler's computer module does not match the specific settings or version required for your model, meaning the system cannot communicate correctly to heat your home.
Your boiler has lost the ability to accurately measure the temperature of the water, so it has turned itself off as a precaution to prevent overheating.
Your boiler has switched itself off because it has detected an overheating issue, which prevents it from running until it cools down and the fault is cleared.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is struggling to pump water around your heating system, likely because the water isn't flowing freely or the pump is stuck.
Your boiler has lost electricity while it was already trying to deal with an internal error, meaning it has now shut down to stay safe.
Your boiler has stopped working because it cannot detect a flame or is not receiving a consistent supply of gas.
Your boiler's air circulation system is failing to start, which has triggered a safety shutdown to prevent the unit from operating without proper ventilation.
BoilerFaultCodes