20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
This boiler uses LED flash patterns
Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →
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 |
|---|---|---|
| 47-283-47 | Comfort 30 | 2013–present |
Tap any card for details
Your boiler has stopped working because the internal fan, which safely exhausts fumes, is not spinning correctly or the system cannot detect it.
Your boiler has detected a problem with the temperature sensor that manages your central heating, meaning it cannot accurately tell how hot the water is.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has lost the ability to measure the temperature of the water being sent to your radiators, so it has shut down to prevent overheating.
Your boiler has stopped working because it failed to light the flame properly, likely due to an issue with the gas supply, the ignition process, or the exhaust system.
Your boiler has detected that it has become dangerously overheated and has shut itself down to prevent damage.
Your boiler has failed to light because it cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is struggling to detect the temperature of your hot water, so it has safely shut down to prevent the system from overheating.
Your boiler has detected that the flue gases are overheating, so it has safely shut itself down to prevent potential damage.
Your boiler has detected an issue with the sensor that monitors the heat of the gases leaving your system, which prevents the boiler from running to keep it safe.
Your boiler has detected that the internal mechanism responsible for venting exhaust gases is not spinning correctly, causing the system to stop working as a safety precaution.
Your boiler has detected that the water pressure is too low, which prevents it from heating up or providing hot water.
Your boiler has detected a problem with its temperature sensor and has stopped working as a safety precaution.
Your boiler has stopped working because it cannot light the gas flame needed to provide heat and hot water.
Your boiler has likely overheated or has air trapped inside, causing it to shut down for safety.
Your boiler has detected a serious internal fault that has caused it to shut down for safety reasons and it will not provide heating or hot water until a professional has inspected it.
Your boiler is struggling to detect the temperature of your hot water, which means it will likely stop providing hot water until the faulty sensor is replaced.
Your boiler has detected that water is not circulating properly through the system, causing it to shut down to prevent overheating.
Your boiler has switched itself off because it has detected a dangerous build-up of heat or a potential problem with the flue gas temperature.
Your boiler has failed to light the gas and has locked itself for safety, which means you currently have no heating or hot water.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes