34 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to detect a flame, so it has safely shut itself down to prevent gas from flowing without being burnt.
Your boiler is failing to light its internal flame, which means it cannot produce any hot water or heating.
Your boiler has detected an issue with the electrical signal to the gas valve, meaning it cannot start the burner to heat your home or water.
Your boiler has stopped working because it has detected an electrical issue during the ignition process and has shut down for safety.
Your boiler has detected an internal computer error that is preventing it from starting up correctly.
Your boiler has detected an internal computer error that is preventing it from operating correctly.
Your boiler has detected an internal electrical problem with the safety component that controls the gas supply, meaning it cannot switch on safely.
Your boiler has detected an internal computer error that is preventing it from starting up correctly.
Your boiler has automatically turned itself off because it has detected that its internal water temperature has become dangerously high.
The internal computer system that controls your boiler has experienced a glitch and can no longer safely operate.
Your boiler's main control computer is experiencing an internal error, preventing it from operating safely.
Your boiler has detected an internal software or hardware error within its control system that is preventing it from operating safely.
Your boiler's internal computer is experiencing a critical error, which is preventing it from operating safely.
Your boiler's internal computer has detected a serious electronic error and has shut down to prevent further damage.
Your boiler has detected that the internal water temperature has become too hot and has automatically shut down to prevent damage.
Your boiler is shutting down because the water returning from your radiators is running much hotter than the system expects, which suggests the water isn't circulating properly.
Your boiler has detected that hot water is flowing in the wrong direction or the sensors are misreading, causing it to shut down to protect the system.
Your boiler is shutting down because it senses that the water inside is heating up far too quickly, often due to a blockage in the system or a pump failing to move the water around.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has stopped working because it cannot confirm that the internal fan, which is essential for safely venting combustion gases, is spinning correctly.
Your boiler has detected that the internal component responsible for pushing exhaust gases safely out of your home is not running as it should, so it has safely shut itself down to prevent unsafe operation.
Your boiler has detected that the water leaving it is significantly hotter than the water returning, suggesting a circulation problem in your heating system.
Your boiler has stopped working because a temperature monitoring component is sending a faulty signal to the control system.
Your boiler has stopped working because it is unable to accurately read the temperature of the water returning to it, causing the system to shut down for safety.
Your boiler has stopped producing hot water because it is misreading the temperature due to a faulty electrical sensor connection.
Your boiler has stopped working because it cannot detect the water flowing through the system.
Your boiler is struggling to read the temperature of the water coming back into the system, which is preventing it from heating your home properly.
Your boiler has lost the ability to read the temperature of the water being sent to your taps, which means it has stopped providing hot water as a precaution.
Your boiler's internal computer has detected a critical electronic error, meaning it has safely shut down to prevent further damage.
Your boiler has detected an internal computer error that is preventing it from operating correctly.
Your boiler is struggling to breathe properly because it cannot pull in enough air to burn the fuel safely.
Your boiler is failing to communicate correctly with other connected boilers in your system, preventing it from starting up correctly.
Your boiler is failing to ignite because it cannot detect a stable flame, so it has safely shut down to prevent gas from building up.
Your boiler has stopped working because an internal electrical safety fuse has blown, meaning the system is unable to power its essential controls.
BoilerFaultCodes