28 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 |
|---|---|---|
| 41-470-23 | Ecoblue 12 System ErP | 2015–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 temperature sensor is providing faulty readings, so the system has shut down to prevent overheating or operating incorrectly.
Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust gases leaving the unit, causing it to shut down for safety reasons.
Your boiler is struggling to accurately read the temperature of the water returning to it, so it has stopped working to prevent potential damage.
Your boiler is struggling to move water through the system effectively, which is causing it to shut down to prevent overheating.
Your boiler has detected that it is overheating and has automatically shut down to prevent damage because the internal pump is not moving water correctly.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that the water pressure inside your heating system is currently too high for safe operation.
Your boiler has stopped working because the amount of water circulating inside your heating system has dropped below the required level.
Your boiler is failing to move hot water around your radiators, likely because the internal pump is blocked, seized, or air is trapped in the system.
Your boiler is trying to start but the flame is not staying lit, which means you currently have no heating or hot water.
Your boiler has detected that the temperature in the exhaust flue is too high, causing it to shut down for safety reasons.
Your boiler has tried to start up several times, but the internal flame is failing to ignite or stay lit.
Your boiler is trying to start but cannot detect a flame, likely because the gas supply is blocked or the ignition system has failed.
Your boiler has attempted to light the gas flame multiple times but has failed, so it has safely shut down to prevent gas from escaping.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not working or communicating correctly, so it has shut down to prevent unsafe operation.
Your boiler has detected an internal hardware error and has safely shut down to prevent further issues.
Your boiler has detected a flame inside the unit when it shouldn't be there, so it has automatically shut down to keep your home safe.
Your boiler has entered a special test or setup mode, which usually happens during a service or when a heating engineer is calibrating the system.
Your boiler has stopped working because it cannot communicate properly with its internal exhaust fan, which is crucial for safety and operation.
Your boiler has temporarily stopped working because it cannot accurately read its internal temperature.
Your boiler has detected an issue with the gas supply reaching the burner, which stops it from operating safely.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler is trying to start up but cannot successfully create or detect the spark needed to light the flame.
Your boiler has detected an issue with the gas supply pressure or the flame sensor, meaning it cannot ignite or stay safely lit.
Your boiler has automatically shut down because it detected dangerously high temperatures inside the unit.
Your boiler has stopped because the water pressure inside the heating system is either too low or too high.
Your boiler has detected trapped air in the system or a problem with the temperature sensor, causing it to temporarily pause heating for safety.
Your boiler is temporarily locked out because it cannot accurately read its internal temperatures or suspects a blockage inside the heating system.
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BoilerFaultCodes