104 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Megaflo System / Baxi Platinum Combi
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Your boiler’s internal computer has encountered a critical communication error and cannot operate safely.
Your boiler’s internal computer has encountered a critical communication error and cannot operate safely.
Your boiler has detected a safety concern or internal failure and has shut itself down to prevent damage.
Your boiler has failed to ignite, meaning it cannot create the flame needed to provide you with heating or hot water.
Your boiler is struggling to circulate water properly or is heating up too quickly, causing it to shut down for safety.
Your boiler has switched itself off because it has become too hot internally, likely due to a lack of water or a blockage preventing water from moving around the system.
Your boiler has shut down because it has either gotten too hot or it is unable to supply gas to the burner.
Your boiler's electronic brain has detected an internal safety error and has shut down for protection.
Your boiler has detected an issue with how the fuel is burning or how the main heat exchanger is performing, causing it to shut down for safety.
Your boiler's main internal computer has developed a serious communication fault and can no longer control the heating process safely.
Your boiler has stopped working because the water pressure in the central heating system is too low or a sensor has failed.
Your boiler has stopped working because the internal computer and its sensors are no longer communicating correctly with each other.
Your boiler is sensing a flame even after it has tried to turn the gas off, which is a safety conflict that requires a professional inspection.
Your boiler is detecting a flame at the wrong time, suggesting that gas might be leaking into the burner when it should be shut off.
Your boiler has stopped working because the internal fan, which safely pushes exhaust gases out of the flue, is not spinning at the correct speed.
Your boiler is struggling to move water through the system properly, which is causing it to shut down to prevent overheating.
Your boiler has stopped working because water is not circulating through the system properly, often due to a pump issue or a closed valve.
Your boiler is currently reheating the hot water cylinder and this message is a status update rather than a critical failure.
Your boiler is currently just doing its normal job of heating up your hot water tank.
Your boiler is currently showing its water temperature and is likely waiting for you to check the system pressure before it resumes normal operation.
Your boiler is simply showing you the current temperature of the water being sent to your radiators, and you can press the reset button to see your system's water pressure instead.
Your boiler has encountered a general operational error, likely due to an interruption in the gas supply or a failure during the ignition process.
Your boiler has tried to light several times but has failed to create a flame, causing the system to shut down for safety.
Your boiler has shut itself down because it has become too hot internally and needs to cool down for safety.
Your boiler has shut down because it is unable to safely discharge exhaust fumes or has detected that the flue system is overheating.
Your boiler has shut itself down for safety because it tried to light several times but couldn't maintain a steady flame.
Your boiler's fan is not spinning at the correct speed, which means it cannot safely clear exhaust gases and has shut down as a precaution.
Your boiler has detected an electrical fault with the sensor that monitors water flow, meaning it cannot safely determine if water is moving through the system.
Your boiler is unable to read the hot water temperature correctly, meaning you likely have no hot water or unstable water temperatures.
Your boiler has detected a fault with the temperature sensor for your hot water, which means it cannot safely heat the water for your taps.
Your boiler has detected an electrical issue with the component that controls the gas supply, causing the system to shut down for safety.
Your boiler has lost water pressure and has stopped working to protect itself from damage.
Your boiler's computer brain has encountered a serious internal error and can no longer control the heating system safely.
Your boiler’s internal computer has encountered a critical communication error and cannot operate safely.
Your boiler's computer has detected a serious internal fault that prevents it from operating safely and reliably.
Your boiler's computer brain has encountered a serious internal error and can no longer control the heating system safely.
Your boiler has too much water inside it, causing the internal pressure to rise to an unsafe level.
Your boiler's main control board has encountered an internal electronic error and is unable to manage the system safely.
Your boiler thinks a flame is present even though it hasn't turned the gas on, usually caused by a blocked drain or a faulty sensor.
Your boiler has detected that its electrical wires are connected the wrong way round at the power source, preventing it from starting up safely.
Your boiler is detecting an issue with the quality or frequency of the electricity coming from your mains supply, causing the system to shut down for safety.
Your boiler’s internal computer has encountered an electronic error and cannot communicate properly with its own components.
Your boiler has detected an internal electrical connection problem that is preventing it from monitoring the system pressure correctly.
Your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, usually resulting in the system shutting down for safety.
Your boiler has detected a problem with the temperature sensor that monitors the water returning from your radiators, preventing the system from operating correctly.
Your boiler is struggling to accurately measure the temperature of your hot water, which usually means the water will either be too cold or the system will stop providing hot water altogether.
Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust fumes, causing the system to shut down for safety.
Your boiler has detected that a temperature sensor responsible for monitoring water returning to the unit has disconnected or broken, preventing it from running safely.
Your boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and can no longer send information to the main control board.
Your boiler's computer brain has encountered a serious internal error and can no longer control the heating or hot water safely.
Your boiler has detected a communication failure or a mechanical fault with the fan, meaning it cannot safely clear exhaust fumes and will not start.
Your boiler has detected a communication failure or a malfunction with the gas valve, meaning it cannot safely light the flame to provide heating or hot water.
Your boiler's electronic control board has detected a communication problem or a mismatch with its internal sensors, causing the system to stop working.
Your boiler has detected an internal communication error, meaning the main control system and the display panel are struggling to talk to each other.
Your boiler is failing to create the spark needed to light the gas burner, meaning your heating and hot water will not work.
Your boiler has detected a problem with the internal sensor that monitors the flame, meaning it cannot confirm it is burning fuel safely and has stopped working.
Your boiler is struggling to spark or maintain a flame because the high-voltage internal ignition cable has developed a fault.
Your boiler is failing to detect the flame it has lit, causing the system to shut down for safety.
Your boiler is struggling to manage the internal water pressure, which is likely causing the system to shut down to prevent damage.
Your boiler has detected a problem with the Pressure Relief Valve assembly, which usually means it is unable to safely manage the internal water pressure.
Your boiler's temperature sensors for the hot water storage tank are sending incorrect signals, preventing the system from heating your water correctly.
Your boiler is struggling to accurately measure the temperature of your hot water, which usually means your taps will only run cold.
Your boiler has sensed that parts of the system have become too hot and has shut itself down as a safety precaution.
Your boiler has detected a communication problem or a electrical fault with the sensor that monitors water pressure, which has caused the system to stop working for safety.
Your boiler has detected an issue with the internal seals or gas components, which usually means it has locked itself out for safety reasons.
Your boiler has detected a leak or a failure in the internal seals that keep the water system watertight, which will likely prevent the unit from operating safely.
Your boiler's internal clock and timer settings have lost power because the backup battery inside the control panel has failed.
Your boiler is unable to light the flame because the ignition system is faulty or damaged, leaving you without heating and hot water.
Your boiler has detected an issue with the sensor that confirms the flame is safely lit, causing the system to shut down for safety.
Your boiler is struggling to direct hot water to your taps or radiators because a mechanical internal valve has stuck or failed.
Your boiler's internal valve is unable to switch between heating your radiators and providing hot water, likely because the motor controlling it has failed.
Your boiler's internal pump has failed or is struggling to circulate water, meaning your heating and hot water will likely stop working.
Your boiler has detected trapped air or a blockage in the internal pump system, which is preventing water from circulating properly to heat your home.
Your boiler has suffered an electrical failure where an internal fuse has blown, meaning the system cannot power its main components to provide heat or hot water.
Your boiler is experiencing a pressure or flow issue with the cold water supply that feeds your hot water tank, meaning you likely have no hot water.
Your boiler's computer brain has encountered a communication error or internal failure related to how it monitors system pressure.
Your boiler has detected a problem with the internal sensor that monitors water pressure, preventing it from heating your home or water safely.
Your boiler has stopped working because the water pressure in the system is too low.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has noticed that the water pressure is getting a bit low and needs a small top-up to keep running efficiently.
Your boiler is simply displaying the current water pressure level, which is perfectly normal and shows that your system is functioning correctly.
Your boiler has reached a critically high water pressure that is unsafe for continued operation.
Your boiler has detected that the water pressure inside the system is dangerously high while it is running, which can put unnecessary stress on your pipework and internal components.
Your boiler has switched itself off because the water pressure is too low for it to run safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has lost water pressure and has shut itself down to prevent damage to the internal components.
Your boiler has detected that there is not enough water pressure in the central heating system to operate safely.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler has detected that the water pressure is too low, which prevents the system from running safely and efficiently.
Your boiler is operating normally and showing that the system pressure is at a healthy level while the water is warm.
Your boiler is operating normally and the water pressure in your system is at an ideal level.
Your boiler is displaying its current water pressure, which is within the normal operating range while the system is running.
Your boiler has shut down because there is too much water pressure in the central heating system.
Your boiler has automatically shut down because the water pressure inside your heating system has become dangerously high.
Your boiler has shut down because there is too much water pressure in the system, which could lead to leaks if not addressed.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has too much water in the system, which puts extra stress on the internal components and may cause it to shut down for safety.
Your boiler has shut down completely for safety reasons and will not provide heating or hot water until it is manually reset or repaired.
Your boiler has stopped working because it failed to light the flame, so it has purposefully shut itself down for safety.
Your boiler has automatically turned itself off because the water pressure inside the heating system has fallen too low to operate safely.
Your boiler is displaying a status message rather than a breakdown code, indicating it is checking water temperatures and simply requires a reset to return to the pressure display.
Your boiler is displaying its current hot water temperature as part of its normal operating sequence and does not indicate a fault.
Your boiler is simply showing you the current hot water temperature setting so you can adjust it to your preference.
This is simply an information screen showing you the current hot water temperature setting rather than a system error.
BoilerFaultCodes