14 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 |
|---|---|---|
| 47-393-27 | Heatmax Combi 24 HE | 2009–2015 |
| 47-393-28 | Heatmax Combi 28 HE | 2009–2015 |
| 47-393-29 | Heatmax Combi 33 HE | 2009–2015 |
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Your boiler is failing to detect that water is circulating properly, which causes it to shut down to prevent overheating.
Your boiler has detected that the temperature of the water inside the system has become too high, causing it to shut down for safety reasons.
Your boiler has failed to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has detected a problem with the fan that pushes dangerous exhaust gases out of your home, so it has turned itself off for safety.
Your boiler is currently unable to read the temperature of the water being sent to your radiators, so it has turned off the heating to prevent any potential overheating.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for your safety.
Your boiler has lost the ability to accurately measure the temperature of the hot water it produces, so it has stopped heating water to prevent overheating.
Your boiler has detected that it is dangerously hot and has automatically shut itself down to prevent internal damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate correctly.
Your boiler has detected that hot water isn't moving around your radiators and pipes as it should, so it has shut down to prevent overheating.
Your boiler has detected that the flue gases are getting too hot, so it has safely shut itself down to prevent any damage.
Your boiler is failing to light because it cannot detect a stable flame or is not receiving enough gas to stay running.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning or communicating correctly, causing the system to stop working to keep you safe.
Your boiler is failing to detect that water is moving correctly through the internal system before it attempts to fire up.
BoilerFaultCodes