14 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 |
|---|---|---|
| 47-930-04 | Combi 30 | 2013–present |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler's control system is unable to read or recognise its internal setup card, meaning it cannot operate safely.
Your boiler has stopped working because it cannot safely expel combustion gases, usually due to an issue with the internal fan or its electrical connection.
Your boiler has safely shut down because the flame inside went out or could not be detected while trying to run.
Your boiler has temporarily stopped working because it cannot accurately measure the temperature of the water flowing through it.
Your boiler has tried to start up several times but failed to ignite the gas safely, so it has locked itself out to prevent any issues.
Your boiler is temporarily shutting down because its sensor thinks a flame is present inside when it shouldn't be.
Your boiler has detected that the electrical supply coming into your home is lower than it needs to be to run safely and properly.
Your boiler has detected that there is not enough water in the system to operate safely, which is usually caused by a small leak or air being bled from radiators.
Your boiler is having trouble communicating with the weather sensor outside your home, but it should still continue to keep you warm in the meantime.
Your boiler has temporarily shut itself down because the internal water temperature got too high.
Your boiler's main electronic control board has not been properly set up or programmed for your specific boiler model.
Your boiler has detected an issue with its internal memory chip or main control board, meaning it cannot operate safely and has shut down.
Your boiler is temporarily unable to accurately measure the temperature of the water returning from your radiators.
Your boiler has temporarily locked itself out for safety because it was restarted too many times in a short period.
BoilerFaultCodes