28 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Potterton Gold
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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 |
|---|---|---|
| 47-393-51 | Titanium 28 Combi ErP | 2015–present |
| 47-393-50 | Titanium 24 Combi ErP | 2015–present |
| 47-393-52 | Titanium 33 Combi ErP | 2015–present |
| 47-393-53 | Titanium 40 Combi ErP | 2015–present |
| 47-393-39 | Titanium 24 | 2012–2015 |
| 47-393-40 | Titanium 28 | 2012–2015 |
| 47-393-41 | Titanium 33 | 2012–2015 |
| 47-393-42 | Titanium 40 | 2012–2015 |
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Your boiler's electronic control system is stuck or miscommunicating, causing the display to flash as it fails to restart.
Your boiler has detected an internal communication error between its main control boards, causing it to stop operating correctly.
Your boiler has detected an internal communication error between its internal parts, preventing it from starting up correctly.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has detected that the water pressure inside the system has dropped too low to operate safely.
Your boiler is failing to circulate water correctly during startup or while running, causing it to shut down for safety.
Your boiler's flue sensor has detected that it is getting too hot, so it has safely shut down to prevent damage.
Your boiler has failed to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is struggling to detect that the fan is spinning correctly, which prevents it from safely igniting and providing heating or hot water.
Your boiler is experiencing a communication fault between its internal control parts, which has caused it to stop working for your safety.
Your boiler has lost the ability to accurately measure the temperature of the water circulating to your radiators, so it has safely shut down to prevent overheating.
Your boiler has detected an issue with the system that removes waste gases, meaning it has safely shut down to prevent any unsafe conditions.
Your boiler has lost the ability to accurately measure the temperature of the hot water, so it has shut down to prevent overheating.
Your boiler has detected that it is dangerously hot and has shut itself down to prevent damage or safety issues.
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 flowing properly around your radiators, causing it to shut down to prevent overheating.
Your boiler has detected that the exhaust gases are becoming too hot, so it has safely shut itself down to prevent damage.
Your boiler is failing to light because it is not receiving enough gas or cannot detect a flame.
Your boiler has stopped working because the mechanical fan responsible for pushing out waste gases is either faulty or not receiving power.
Your boiler has detected that water is not circulating properly before it starts the heating process, meaning it cannot safely turn on.
Your boiler has stopped working because it can no longer accurately read how hot the internal water temperature is.
Your boiler has stopped working because it cannot correctly read the temperature of the gases leaving it and has shut down as a safety precaution.
Your boiler has detected that it is getting dangerously hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to push water around your heating system, which means it cannot provide hot water or heating until the flow is restored.
Your boiler has detected that it is running too hot or that a sensor measuring the exhaust fumes is faulty, so it has safely shut down to prevent damage.
Your boiler has failed to light because it cannot detect a flame, likely due to a gas supply issue or a ignition problem.
Your boiler has detected that the internal air extraction fan is not spinning at the correct speed, which prevents the unit from operating safely.
BoilerFaultCodes