29 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 |
|---|---|---|
| 47-387-15 | i-mini2 c24 | 2022–present |
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Your boiler's temperature sensor for hot water has stopped working correctly, meaning your hot water may be too hot, too cold, or not work at all.
Your boiler has lost communication with its wall-mounted temperature control, meaning it doesn't know when to turn your heating on or off.
Your boiler has detected that the water is getting too hot too quickly, likely because it is not circulating through the system properly.
Your boiler has detected that there is not enough water in the system to operate safely, causing it to shut down temporarily.
Your boiler has started to light but the flame has gone out unexpectedly, often because the gas supply is interrupted or a sensor cannot detect the fire.
Your boiler has detected an issue with the fan, which means it cannot safely exhaust waste gases and has shut down as a precaution.
Your boiler has lost its ability to measure the temperature of the water leaving the unit, meaning it cannot operate safely and has shut down.
Your boiler's internal sensor that monitors the temperature of the water leaving the unit has stopped working, preventing the system from heating up correctly.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators, causing the system to shut down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, meaning it cannot operate safely or efficiently.
Your boiler is having trouble communicating with the external thermometer that checks the weather outside, which can confuse its heating settings.
Your boiler is not receiving enough electrical power from the grid to operate safely.
Your boiler's internal computer has developed an electronic fault and can no longer control the heating system safely.
Your boiler is unable to create the spark needed to light the gas and start the heating process, meaning it will not fire up.
Your boiler has identified that the internal pump, which moves water around your pipes, is stuck or jammed.
Your boiler's internal pump has stopped working, which means hot water cannot be circulated around your radiators or taps.
Your boiler has detected that the electricity coming into your home from the national grid is set at too high a voltage, which could damage the internal electronics.
Your boiler's internal pump has stopped circulating water, which means your heating and hot water will not work until the component is repaired.
Your boiler has detected an internal electrical problem with the part that controls gas flow, so it has shut down as a safety precaution.
Your boiler's hot water sensor is not working correctly, meaning your taps might not get hot or the temperature could be inconsistent.
Your boiler has shut down because it is getting too hot too quickly, usually because the water isn't flowing through the system as it should.
Your boiler has tried to restart five times in a short period and has locked itself out to prevent further damage.
Your boiler has stopped working because its exhaust pipe or drainage tube is likely blocked, preventing it from starting safely.
Your boiler has got too hot and has shut itself down for safety, meaning you have no heating or hot water until the system cools and is reset.
Your boiler has tried to light several times but cannot establish a flame, meaning it has shut down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit, causing it to shut down as a safety precaution.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators, preventing it from heating correctly.
Your boiler detects a flame when it hasn't actually told the gas valve to open yet, which is a safety conflict.
Your boiler has failed to ignite and has locked itself out for safety reasons after multiple unsuccessful attempts to start.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes