44 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 |
|---|---|---|
| 41-283-61 | MURELLE PRO HE 20 R MkII | 2017–present |
| 41-283-62 | MURELLE PRO HE 30 R MkII | 2017–present |
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Your boiler has shut down because it detected that exhaust gases are not being cleared safely from the flue system.
Your boiler has stopped working because the water pressure inside the system is too low.
Your boiler has detected that the water pressure is too high, which can cause the system to stop working correctly or leak.
Your boiler has detected a problem with the temperature sensor that manages your hot water, which may cause your hot water to stop working or fluctuate in temperature.
Your boiler has stopped working because a sensor that monitors the temperature of the water leaving the unit has failed or has a loose connection.
Your boiler has failed to light the flame, which means it cannot heat your water or radiators.
Your boiler has overheated because the water temperature inside the unit has reached an unsafe level, causing it to shut down for safety.
Your boiler is having trouble detecting a flame, which prevents it from firing up to provide heating or hot water.
Your boiler has stopped heating because water is not moving through the system properly.
Your boiler has detected an issue with a secondary sensor, often caused by incorrect electronic settings or a wiring problem.
Your boiler has stopped working because it cannot communicate with the component that controls the gas flow.
Your boiler's computer has been set to the wrong ventilation mode, causing it to shut down for safety because it thinks it is installed in a different type of building setup.
Your boiler has detected that the exhaust gases are too hot or the sensor that monitors them has failed, causing the system to shut down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler has stopped working because the internal computer has lost communication with the fan that clears exhaust gases.
Your boiler has shut down because the internal water drainage system is backed up or blocked, often due to a frozen or clogged outlet pipe.
Your boiler has been manually reset too many times in a short period and has temporarily locked itself for safety reasons.
Your boiler has detected that the electricity supply coming into your home is too low for it to operate safely.
Your boiler has detected an issue with the electrical power timing coming from the grid or your home's backup power source, meaning it cannot operate safely.
Your boiler is failing to stay lit and has stopped working after several unsuccessful attempts to keep a flame going.
Your boiler has detected that one of the buttons on the control panel is stuck or faulty, which is preventing the unit from working correctly.
Your boiler is having trouble 'talking' to your thermostat or external controls, which means it might not know when to turn on or off.
Your boiler has detected an internal electronic error or a problem with the gas connection that is preventing it from lighting safely.
Your boiler has shut down because the water is getting too hot too quickly, indicating that the water is not circulating through the system correctly.
Your boiler has paused operation because it needs to re-calibrate its internal temperature sensors to ensure it is heating efficiently and safely.
Your boiler has detected that a temperature sensor is not sitting correctly on its pipe, meaning it cannot accurately monitor the heat leaving the unit.
Your boiler has detected a communication error with its internal temperature monitoring system, which prevents it from heating up safely.
Your boiler has detected an electrical fault with the gas valve control system, preventing it from safely lighting the burner.
Your boiler has detected an internal electrical issue with the gas control valve, meaning it cannot safely regulate the fuel it needs to stay lit.
Your boiler has detected an internal electrical problem with the gas valve, preventing it from safely controlling the fuel flow.
Your boiler has detected an internal communication error or a fault within the gas valve control system, preventing it from firing up safely.
Your boiler has detected an issue with the air and gas mixture during ignition and has shut down for safety because the exhaust or air supply might be blocked.
Your boiler has stopped working because it has failed to ignite or maintain a flame several times in a row.
Your boiler is struggling to burn gas properly, which is usually caused by air in the pipes or a blockage in the flue vent.
Your boiler is struggling to operate because it isn't receiving a steady or sufficient supply of gas from the main line.
Your boiler's internal computer has locked itself to prevent damage and will likely need professional repair to work again.
Your boiler is struggling to maintain a steady flame and has shut down as a safety precaution.
Your boiler is struggling to manage its flame correctly and has shut down as a safety precaution.
Your boiler has detected an issue with how it mixes air and gas for the flame, causing it to shut down for safety.
Your boiler is struggling to burn gas correctly and cannot reach its required power levels to generate heat.
Your boiler is struggling to keep a steady flame alight, causing the system to stop working as a safety precaution.
Your boiler has shut down because it cannot safely expel exhaust fumes, usually due to a blockage in the chimney or pipe leading outside.
Your boiler has encountered a digital communication error while trying to start up following a power reset or internal check.
Your boiler's internal computer has suffered a total electronic failure and can no longer control the heating system.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes