47 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 |
|---|---|---|
| 41-116-08 | Ecosystem 27 RFFI microCONDENS Series | 2002–2007 |
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Your boiler has stopped working because it is not receiving a reliable supply of gas to create a flame.
Your boiler has failed to light the flame after trying three times, so it has safely shut down to prevent wasting gas.
Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler has detected an internal combustion error and has stopped working as a safety precaution.
Your boiler has detected a communication error with its internal control system and needs a simple restart to try and clear the fault.
Your boiler is experiencing an internal error that has caused it to stop working, but it may simply need a manual nudge to restart properly.
Your boiler has stopped heating because it is struggling to move water through the system, often because the water pressure is too low or the system is blocked.
Your boiler has detected an internal error and needs a simple manual reset to try and clear the system.
Your boiler is struggling to clear exhaust gases effectively because the internal fan responsible for moving air is not operating as it should.
Your boiler has encountered a general internal communication error and needs to be restarted to attempt to clear the fault.
Your boiler has failed to start up because it could not light the gas flame after several attempts.
Your boiler has failed to light after several attempts because it cannot detect that the water inside is heating up properly.
Your boiler has detected that the water inside the heating system has reached a dangerously high temperature and has shut itself down to prevent damage or overheating.
Your boiler has unsuccessfully tried to ignite its flame multiple times and has now locked itself to prevent a gas build-up.
Your boiler has detected that a flame is still present even though it has tried to switch the gas off.
The boiler has detected a flame inside when it hasn't actually started to release gas yet.
Your boiler is failing to detect that water is moving through the system, so it is refusing to ignite to protect itself.
Your boiler is struggling to detect water flow, which means it cannot safely turn on the heating or provide hot water.
Your boiler is currently unable to safely remove waste gases from the system, so it has stopped working to prevent a risk of dangerous fumes entering your home.
Your boiler's computer is experiencing an internal error and cannot properly check or control the system, meaning it needs an expert to reset or replace the main control unit.
Your boiler is failing to ignite because it cannot confirm that the internal fan is moving air correctly, so it has shut down as a safety precaution.
Your boiler has detected that it is running too hot and has automatically switched itself off to prevent internal damage.
Your boiler has detected a problem with the flame sensing mechanism, meaning it cannot safely ignite or prove that a flame is present.
Your boiler is struggling to read its own temperature correctly because the sensor responsible for monitoring the heat has developed a fault.
Your boiler has switched off because the safety sensor for your underfloor heating system has detected that the water temperature has become too high.
Your boiler has detected an internal fault that is preventing it from operating, and the system needs to be checked by a professional to identify the root cause.
Your boiler has detected an internal fault that is preventing it from operating safely.
Your boiler has detected an internal electrical communication fault between its main control boards, which prevents the system from operating safely.
Your boiler has detected an internal electrical communication error, which means it cannot safely control its own operations and has shut down to protect itself.
Your boiler has detected an internal issue with the gas control system that prevents it from working safely.
Your boiler has detected a communication error with its internal electronics, meaning it cannot safely operate and has shut down to prevent damage.
Your boiler has detected a critical failure in the internal electronic control system that prevents it from firing safely.
Your boiler has detected a communication error with its internal computer, which is preventing it from heating your home or water correctly.
Your boiler has detected a critical internal communication failure and has locked itself down for safety.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has lost the signal from the sensor that measures how hot your tap water is, so it has stopped heating your water to prevent overheating.
Your boiler is unable to read the temperature of your hot water properly, so it has safely shut down to prevent overheating.
Your boiler is struggling to detect the temperature of the water flowing into your underfloor heating system, likely due to a damaged sensor or a loose wire.
Your boiler has detected a flame when it should be turned off, which indicates a serious safety issue that requires immediate attention from a professional.
Your boiler has detected that the electricity supply wires have been connected incorrectly, which is preventing it from starting up safely.
Your boiler is struggling to detect a consistent electricity supply, which is preventing it from starting up reliably.
Your boiler has detected an issue with the internal sensor that monitors the flame, preventing it from safely igniting and staying on.
Your boiler has lost the signal from the sensor that monitors the temperature of the water being sent to your radiators, which prevents it from heating your home safely.
Your boiler has lost the ability to read the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler has stopped working because one of its internal temperature sensors is providing an inaccurate reading due to a faulty electrical connection.
Your boiler's internal sensor that monitors the temperature of the returning water has developed an electrical fault and is preventing the system from heating correctly.
Your boiler's main computer is having an internal communication error and cannot safely operate the heating or hot water.
BoilerFaultCodes