10 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 |
|---|---|---|
| 47-393-47 | Promax 24 Combi ErP | 2008–present |
| 47-393-48 | Promax 28 Combi ErP | 2008–present |
| 47-393-49 | Promax 33 Combi ErP | 2008–present |
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Your boiler has lost its ability to accurately measure the temperature of the water being heated for your radiators, causing the system to shut down for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler is struggling to provide hot water because its internal temperature sensor has stopped working correctly.
Your boiler has become too hot and has automatically shut down for safety, preventing internal damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that hot water is not moving around the system correctly, causing it to shut down to prevent overheating.
Your boiler has switched itself off because it detected that the exhaust gases have become too hot, which is a safety feature to protect the internal parts.
Your boiler has failed to light, likely because gas isn't reaching the burner or the spark isn't igniting the flame.
Your boiler has stopped working because the fan that clears exhaust gases is not spinning at the correct speed.
The water isn't moving through your boiler properly or is heating up too quickly, causing the system to shut down to prevent overheating.
BoilerFaultCodes