66 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an internal communication error and has safely shut itself down as a precaution.
Your boiler has failed to light the flame properly and has stopped attempting to heat your home or water for safety reasons.
Your boiler has detected a false flame signal, meaning the system thinks the burner is lit when it should be turned off.
Your boiler has detected a flame signal when it shouldn't have, but it is currently attempting to clear this error automatically.
Your boiler has detected that its internal configuration settings have not been set correctly, causing it to stop operating.
Your boiler's main internal controller has lost its connection, meaning it cannot receive signals from the display panel to operate your heating and hot water.
Your boiler has detected that it is not receiving enough water flow to operate safely or effectively.
Your boiler has detected an issue related to the flow of water inside the unit, which has caused it to stop working to protect itself from potential overheating.
Your boiler has failed to ignite or has lost the flame during operation because it is not receiving a consistent supply of gas.
Your boiler has detected an issue with the air supply or exhaust ventilation that prevents it from firing up safely.
Your boiler has detected an issue with the sensors that monitor the water flow, which is preventing it from firing up correctly.
Your boiler has detected a problem with the internal fan that controls the airflow needed to operate safely.
Your boiler has detected an issue with the air supply or exhaust system, meaning it cannot operate safely and has shut down to prevent damage.
Your boiler has detected an issue with the airflow or exhaust system, meaning it cannot operate safely and has shut itself down.
Your boiler has detected that it is not effectively removing waste gases produced during the heating process, causing it to shut down for safety.
Your boiler is struggling to breathe properly because the pipework that lets out waste gases or takes in fresh air is blocked or damaged.
Your boiler has detected an issue with the air flowing through the flue system, causing it to shut down for safety.
Your boiler has detected an issue with the water pressure sensor, preventing it from knowing if there is enough water to safely heat your home.
Your boiler has detected an issue with the air flowing through the system, preventing it from starting safely.
Your boiler is experiencing a communication failure between the control panel and the main operating system preventing it from firing up correctly.
Your boiler has detected an issue with the air supply or exhaust ventilation system that prevents it from firing safely.
Your boiler has detected an issue with the sensor that tracks the flow of water, which is preventing the system from operating correctly.
Your boiler has detected a problem with the water flow or pressure sensors that prevents it from firing up reliably.
Your boiler has detected an internal communication error between its main computer and the internal control systems, which prevents it from operating safely.
Your boiler has detected an internal communication error between its main computer and the internal control system, causing it to stop working for safety reasons.
Your boiler has detected an internal communication problem with the air pressure sensor, which is preventing it from safely starting up.
Your boiler's fan is failing to run correctly, which prevents it from safely venting gases, so the system has shut down to protect your home.
Your boiler's external temperature sensor is reporting an issue, which may cause it to run inefficiently or struggle to heat your home correctly.
Your boiler has reached its programmed service timer and is simply reminding you that it is time to have a professional technician perform a routine maintenance check to prevent limescale buildup.
Your boiler has detected an internal communication or software management error that requires a professional to reset or update its internal settings.
Your boiler's main control unit and the display panel are having trouble 'talking' to each other, which prevents the system from operating correctly.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that parts inside are getting too hot and has automatically shut down to prevent damage.
Your boiler has detected that the gases leaving the unit are getting too hot, so it has safely shut down to prevent damage.
Your boiler has stopped because the internal flame has unexpectedly gone out while it was running.
Your boiler has detected an issue with its internal air extraction system, which means it cannot safely clear emissions and has shut down to prevent any risk.
Your boiler has detected a potential issue with the gas supply or the internal gas valve, and to keep you safe, it has automatically locked itself to prevent operation.
Your boiler is struggling to detect the movement of water, which means it will prevent your hot water or heating from starting to protect the system from overheating.
Your boiler's main control computer is experiencing a communication or processing error, which has caused it to stop working for safety reasons.
Your boiler has detected that parts inside are getting dangerously hot and has shut itself down to prevent damage.
Your boiler has detected that the temperature of the gases leaving the flue is higher than it should be, so it has safely shut itself down to prevent damage.
Your boiler is struggling to clear exhaust gases safely, so it has stopped working to prevent any risk.
Your boiler has detected that the sensor monitoring the heat of the exhaust gases is not reading correctly, which prevents it from operating safely.
Your boiler is failing to ignite because it cannot regulate the gas supply correctly, which means you currently have no heating or hot water.
Your boiler is struggling to detect the outside temperature, so it is defaulting to a basic heat setting to keep your home warm while ignoring external weather conditions.
Your boiler is struggling to accurately measure how much water is inside the system, which is preventing it from firing up safely.
Your boiler’s internal computer is confused because its physical configuration switches are set incorrectly, preventing it from starting safely.
Your boiler's electronic display and its internal computer are failing to communicate with each other, meaning the unit cannot receive instructions or show system status.
Your boiler's air pressure sensor is failing to communicate properly, which means the safety system is preventing the burner from lighting to ensure the unit operates safely.
Your boiler has detected that the water flow pipes are connected in the wrong order or that the heat is moving in the wrong direction, causing the system to shut 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 detect when you turn on a hot tap, so it isn't heating the water for your shower or kitchen taps.
Your boiler is struggling to detect the temperature of your hot water supply because a connection to its temperature sensor has been lost or interrupted.
Your boiler's electronic control panel is experiencing a communication fault, which prevents the display from responding or controlling the unit properly.
Your boiler's electronic control board is having trouble talking to the display panel, meaning it cannot currently receive commands or show status updates.
Your boiler has lost its digital connection to your room thermostat, meaning it cannot receive signals to turn the heating on or off.
Your boiler's internal clock has lost its settings, which usually means the system cannot keep time to manage your heating schedule correctly.
Your boiler is having trouble communicating with your wall-mounted thermostat or smart control system, which prevents it from knowing when to turn on your heating.
Your boiler is struggling to detect the water flow or pressure levels, which is likely preventing it from starting up properly.
Your boiler has detected a minor internal software or communication glitch and needs to be restarted to clear the error.
Your boiler is struggling to circulate hot water properly, which means it cannot reliably provide hot water to your taps or showers.
Your boiler is failing to light the internal flame, which means it cannot produce any hot water or heating for your home.
Your boiler's computer does not recognise which specific version of the appliance is installed, preventing it from functioning correctly.
Your boiler is struggling to light its internal flame, which means it has automatically shut down to prevent gas from building up.
Your boiler has reached its programmed time for a routine annual service as a reminder to ensure it remains safe and efficient.
BoilerFaultCodes