6 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 |
|---|---|---|
| 47-116-16 | Microcombi 23 MFFI | 2000–2007 |
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Your boiler has detected that water is not circulating correctly through the system, so it has safely shut down to prevent internal damage.
Your boiler is having trouble controlling the size of its internal flame, which means it cannot safely heat your water or home.
Your boiler is struggling to clear exhaust gases out through the flue, so it has safely shut itself down to prevent fumes from building up.
Your boiler has detected that the water temperature has risen too high and has safely shut itself down to prevent overheating.
Your boiler has detected an internal safety issue and has shut itself down to prevent any damage or danger, meaning you currently have no heating or hot water.
Your boiler has stopped because the water pressure inside your heating system has dropped too low to operate safely.
BoilerFaultCodes