126 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Heat
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Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage.
Your boiler is able to heat your hot water, but it is struggling to produce enough heat for your radiators because it cannot switch to full power.
Your boiler is stuck on the heating setting and cannot control its temperature properly, leading to overheating or a lack of hot water.
Your boiler is working correctly and is currently providing heat to your radiators.
Your boiler is struggling to keep up with the amount of hot water you are using, or the flow of water through the system is too weak to heat it properly.
Your boiler is currently working as it should to provide hot water to your taps or shower.
Your boiler is perfectly fine, it has simply paused for a few minutes to protect itself from turning on and off too frequently.
Your boiler is working fine to heat your hot water, but it is failing to send heat to your radiators.
Your boiler is struggling to direct heat to your radiators while potentially making your hot water tank dangerously hot.
Your boiler is working fine to heat your radiators, but it isn't heating your hot water tank as it should.
Your boiler is temporarily pausing between firing cycles to prevent the system from turning on and off too frequently, which protects the internal components from unnecessary wear.
Your boiler is working perfectly and is currently sitting in standby mode because it has already reached the required temperature.
Your boiler is currently trying to light the flame to start provide heating or hot water, which is a normal part of its startup sequence.
Your boiler is performing a routine safety check by blowing air through the system to clear any leftover gases before or after it fires up.
Your boiler has paused briefly because the water inside has reached its maximum set temperature and is waiting for it to cool down before firing up again.
Your boiler has detected an electrical fault in its control system, which has caused it to shut down for safety reasons.
Your boiler has detected a loose or faulty safety connection near the flue, which is preventing it from firing up reliably.
Your boiler has detected that a safety sensor meant to monitor exhaust gases is disconnected or has failed, causing the system to shut down for protection.
Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler has detected an inconsistent temperature reading between its internal sensors, causing it to shut down to prevent damage.
Your boiler is shutting down because it thinks the water inside is heating up far faster than it should, which often indicates a trapped air bubble or a blockage stopping the water from moving properly.
Your boiler has detected that the water leaving the heater is much hotter than the water returning to it, meaning the system cannot circulate heat properly.
Your boiler has shut down because a safety sensor has detected that the internal heat exchanger is getting too hot.
Your boiler has detected that there is not enough water circulating through the system or that the water is heating up too quickly.
Your boiler is overheating because the water inside it is getting too hot too quickly, causing the system to shut down for safety.
Your boiler has detected that water is leaving the unit much hotter than it is returning, which usually means the water isn't circulating through your radiators fast enough.
Your boiler is trying to start but the flame is not catching or staying lit, so it has shut down for safety to prevent gas from escaping unburnt.
Your boiler has encountered a serious internal error that has forced it to shut down for safety reasons and it requires a professional reset.
Your boiler has detected that the internal water temperature is dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has stopped working because it has either detected an overheating issue or an internal electrical safety fuse has failed.
Your boiler has shut itself down because it detected that the water inside has become dangerously overheated.
Your boiler has detected an internal electrical fault with a safety component, causing it to shut down to prevent any unsafe operation.
Your boiler has lost its connection to one of its safety sensors, so it has shut down to keep your home safe.
Your boiler has lost the ability to accurately measure the temperature of the water circulating inside it, so it has shut down as a precaution to prevent overheating.
Your boiler's temperature-sensing component is not registering a signal, meaning the system has stopped operating to prevent overheating.
Your boiler has shut down because a sensor has detected that the water inside is getting too hot.
Your boiler has shut down because it has detected it is getting too hot or an internal safety fuse has blown.
Your boiler has reached an unsafely high temperature and has shut down to prevent damage or overheating.
Your boiler has detected an electrical fault with one of its main internal temperature sensors, causing the system to shut down for safety.
Your boiler has lost its connection to an internal safety sensor and has shut down as a precaution to prevent damage.
Your boiler has stopped working because an internal temperature sensor has developed an electrical fault and can no longer read the heat levels correctly.
Your boiler has lost its connection to the internal thermometer that monitors water temperature, meaning it cannot safely heat your home or water.
Your boiler's computer brain has encountered an internal error and cannot operate safely, meaning your heating and hot water will not work.
Your boiler's electronic control system has frozen or locked up, preventing it from starting or responding to your commands.
Your boiler's electronic control system has frozen or locked up, preventing it from functioning correctly.
Your boiler’s control panel has been locked manually or due to a button sequence error, preventing you from changing any settings.
Your boiler’s control panel has become locked or entered a restricted mode, preventing you from changing any settings or operations.
Your boiler's computer system has encountered an internal error and cannot safely manage the heating process, meaning the unit will need attention from a professional.
Your boiler is attempting to start but is failing to detect a flame, causing it to shut down for safety.
Your boiler is continuing to burn gas even when it should have shut down, which means it cannot stop heating correctly.
Your boiler is lighting up for a split second before immediately shutting itself off because it cannot detect the flame.
Your boiler has successfully lit, but the flame has unexpectedly gone out while it is trying to heat your home.
Your boiler is failing to light the gas flame properly, meaning it cannot heat your water or radiators.
Your boiler is still detecting a flame even after it should have turned off, which suggests gas may still be flowing into the unit when it shouldn't be.
Your boiler is lighting up but the flame goes out straight away, preventing the system from producing heat.
Your boiler is successfully lighting, but it cannot stay lit and keeps cutting out while it is running.
Your boiler's computer system has encountered a major internal error and can no longer safely operate.
Your boiler's internal computer has developed a fault and can no longer safely manage the heating or hot water functions.
Your boiler's main internal computer has developed a fault and is no longer able to control the heating process.
Your boiler has lost power while trying to clear an old error, or the reset button wasn't held down for long enough.
Your boiler's internal computer has lost power or suffered a hardware failure, meaning it cannot control the heating or hot water functions.
Your boiler's main internal computer has developed a fault and is unable to control the heating system correctly.
Your boiler's internal computer has developed a fault and is unable to send the correct signals to start the heating process.
Your boiler is failing to confirm that air is moving properly through its internal venting system, preventing it from lighting safely.
Your boiler has lost its connection to an internal sensor or controller, meaning it cannot communicate properly to start the heating process.
Your boiler's main internal computer has developed a fault and is no longer communicating correctly with the rest of the system.
Your boiler's main control board has lost communication with its internal memory chip, meaning it cannot process the settings needed to run safely.
Your boiler's internal computer is having trouble measuring its own temperature, which prevents it from operating safely.
Your boiler's internal computer has suffered a technical failure and cannot communicate with the rest of the system.
Your boiler has stopped working because of an internal communication error between the main control board and the gas valve.
Your boiler's computer brain has suffered a serious internal electronic failure and can no longer communicate with the heating system.
Your boiler's main control computer is unable to communicate with its internal memory chip, meaning it cannot access the settings needed to run safely.
Your boiler has detected a critical internal computer error and has shut down to protect itself, meaning your heating and hot water will not work.
Your boiler's internal computer has encountered a serious problem that is preventing it from operating safely or correctly.
Your boiler has detected a critical internal software or hardware error that prevents it from operating safely.
Your boiler’s internal computer has flagged a critical error that prevents it from starting safely.
Your boiler’s internal control computer has encountered a serious error and can no longer safely operate.
Your boiler's computer has detected an internal error and has shut itself down to prevent damage, meaning you currently have no heating or hot water.
Your boiler's computer system has encountered an internal error and has shut down to prevent damage, meaning you currently have no heating or hot water.
Your boiler is struggling to breathe properly because there is a blockage or too much debris in the air intake or exhaust system.
Your boiler has detected that the water inside the heating system is getting too hot and has automatically shut down to prevent damage.
Your boiler has stopped working because the fan that helps remove waste gases is not spinning or communicating correctly with the system.
Your boiler is shutting down because it has detected that the water returning from your radiators is hotter than it expects, suggesting the system is struggling to circulate water properly.
Your boiler has stopped working because it cannot properly measure the temperature of the water coming back into the system.
Your boiler has shut down because a safety sensor has detected that the burner area is getting too hot or is failing to register a secure connection.
Your boiler has stopped working because its internal sensors or control system have detected a technical communication error.
Your boiler has lost communication with one of its internal sensors, meaning it cannot accurately monitor temperatures to run safely.
Your boiler is confused because two temperature sensors have been mixed up or are misreading the heat levels, preventing it from starting safely.
Your boiler is unable to create a spark to light the gas, meaning your heating and hot water will not work.
Your boiler is shutting down because it detects the water is heating up too rapidly for the system to safely handle.
Your boiler has shut down because the mixture of gas and air required for a safe flame is incorrect, often due to a blockage or a dirty internal component.
Your boiler is failing to detect enough incoming gas pressure to operate safely and has shut itself down to prevent potential issues.
Your boiler is unable to light the flame because the gas supply is blocked or a safety sensor is cutting out.
Your boiler is not receiving a steady supply of gas or has air trapped in the pipes, preventng the flame from lighting properly.
Your boiler has stopped working because it cannot detect that the internal fan, which is essential for safely venting exhaust gases, is spinning correctly.
Your boiler has failed to detect a flame, which means it cannot stay on safely and has stopped working for your protection.
Your boiler has detected that the internal fan is moving inconsistently, so it has shut itself down to ensure the boiler burns fuel safely.
Your boiler has detected an issue with the electrical power supply to the unit while it was running.
Your boiler has detected that water is failing to circulate correctly, meaning it is getting too hot in one part of the system compared to another.
Your boiler has experienced an internal electrical short circuit which has likely blown a protective fuse, causing it to stop working entirely.
Your boiler has detected a faulty temperature sensor reading, which is preventing it from safely heating your water and radiators.
Your boiler has experienced a temporary software or ignition glitch and simply needs to be rebooted to clear the error.
Your boiler has detected a faulty temperature sensor reading, which is preventing the system from heating your water correctly.
Your boiler has detected that gas is potentially still flowing or a flame signal is present when it should be turned off, which is a safety concern.
Your boiler's internal control module is failing to communicate with the fan, causing the system to shut down immediately after trying to start.
Your boiler has detected a problem with how it monitors gas supply pressure, meaning it cannot safely confirm there is enough fuel to stay lit.
Your boiler has lost the ability to read the temperature of the water because a sensor is no longer connected or has failed.
Your boiler's internal communication chip is either faulty or has come loose, causing the system to stop working.
Your boiler has detected a faulty connection to a temperature sensor, which is preventing it from monitoring heat levels safely and shutting it down to prevent damage.
Your boiler has stopped working because it has lost a secure electrical connection to the valve that controls the gas supply.
Your boiler has lost communication with your wall thermostat, meaning it cannot receive the signal to turn on your heating.
Your boiler has lost its electrical power supply or there is a fault with the incoming electricity to the unit.
Your boiler’s internal control system has encountered a critical electronic failure that it cannot clear itself.
Your boiler has detected a critical internal software or hardware error that prevents it from starting safely.
Your boiler is producing more heat than your hot water tank can safely handle, causing the system to stop for protection.
Your boiler's main control unit has detected a serious internal system error and has shut itself down as a safety precaution.
Your boiler is struggling to control how much water flows through the system, which can prevent it from heating up correctly.
Your boiler has developed an internal electrical fault that is preventing it from starting up safely.
Your boiler has detected a sensor issue that is preventing it from safely starting up, meaning you currently have no heating or hot water.
Your boiler’s internal computer has developed a fault and can no longer communicate with the rest of the system, causing it to stop working.
Your boiler's internal computer has developed a fault and is unable to manage the heating system correctly.
Your boiler's main internal computer has developed a fault and can no longer control the heating system correctly.
Your boiler’s main control screen or internal computer has developed a fault and can no longer communicate with the rest of the system.
Your boiler’s main computer screen or internal control board has developed a fault and is no longer communicating correctly with the rest of the system.
Your boiler's internal computer parts are unable to talk to each other correctly because they are not compatible.
Your boiler has lost all power and is completely unresponsive, meaning you currently have no heating or hot water.
BoilerFaultCodes