19 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 |
|---|---|---|
| 41-116-01 | Genus 27 RFFI System | 1998–2007 |
| 47-116-13 | Genus 30 MFFI | 1999–2007 |
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Your boiler has detected that it is overheating and has shut itself down as a safety precaution to prevent damage.
Your boiler is struggling to pump water around your heating system effectively, which prevents it from working properly.
Your boiler has detected that hot water is not flowing correctly through your radiators or pipes, meaning it has shut down to prevent itself from overheating.
Your boiler is having trouble pushing out exhaust gases, so it has safely shut itself down to prevent any risk.
Your boiler's main control computer is experiencing a communication error or internal fault that is preventing it from running properly.
Your boiler has stopped working because it cannot correctly detect the temperature of the water leaving it to provide heating.
Your boiler has stopped heating because a temperature sensor is sending an incorrect electrical signal that the system cannot interpret.
Your boiler has detected that the temperature in your underfloor heating system is too high and has shut itself down to prevent damage.
Your boiler is confused and thinks there is a flame inside while the gas supply is already switched off, which has caused it to shut down for safety.
Your boiler has detected an internal communication error in its main computer, causing it to shut down for safety reasons.
Your boiler is struggling to accurately measure the temperature of the water flowing through your heating system, so it has stopped working safely to prevent internal overheating.
Your boiler has detected multiple failed attempts to function and has automatically locked itself out to prevent further issues.
Your boiler tried to light its burner but failed to detect a flame, so it has safely shut down to prevent gas buildup.
Your boiler is struggling to detect the temperature of your hot water, which means it will stop heating your taps until the issue is resolved.
Your boiler is struggling to detect the temperature of your hot water because a sensor is sending an incorrect electrical signal.
Your boiler is struggling to detect the temperature of your hot water cylinder, which means it cannot safely heat your water supply.
Your boiler is struggling because it cannot accurately read the temperature of the water stored in your hot water cylinder.
Your boiler has detected that the water inside the hot water storage tank has become dangerously hot and has shut down to prevent damage or safety risks.
Your boiler is struggling to read the temperature in your home because the connection to your wall-mounted control unit is faulty.
BoilerFaultCodes