17 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 |
|---|---|---|
| 41-470-74 | 824 SYSTEM | 2019–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 has detected an issue with the internal wiring or the valve that controls the gas supply, meaning it has safely shut down to prevent unsafe operation.
Your boiler has detected a problem with the temperature sensor on the central heating system, so it has temporarily stopped working to prevent overheating.
Your boiler has temporarily stopped working because a sensor that measures the temperature of the water returning from your radiators is not reading correctly.
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 has temporarily stopped because it detected a problem with the temperature readings between the flow and return pipes.
Your boiler has stopped working because it has detected a lack of water flowing through the system, which can cause it to overheat.
Your boiler has automatically shut down because the temperature around the exhaust flue became dangerously high, triggering a crucial safety lock.
Your boiler has stopped working because the amount of water circulating inside your heating system has dropped below the required level.
Your boiler has detected that water is not moving correctly through the internal heating system, preventing it from heating your home or water safely.
Your boiler has lost its flame while it was running, meaning it cannot stay alight to provide 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 stopped working because it cannot light its internal flame, which is usually due to an issue with the gas supply or the ignition system.
Your boiler has failed to ignite or has lost its flame because it isn't receiving the gas it needs to stay lit.
Your boiler has lost its connection to the gas supply due to an internal technical fault and cannot stay lit.
Your boiler has stopped working because it cannot properly clear exhaust gases, so it has safely shut itself down to prevent a hazard.
Your boiler has lost the ability to measure the temperature of your hot water, so it has safely shut down to prevent overheating.
Your boiler has temporarily locked out because it cannot detect a steady gas supply or has encountered an internal safety check failure.
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BoilerFaultCodes