159 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
This boiler uses LED flash patterns
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Your boiler has detected a minor fluctuation in the water circulation system, but it is still operating safely and does not require immediate intervention.
Your boiler has detected an internal issue where it thinks it should be running but has stopped a critical internal circulation component for safety.
Your boiler is having trouble communicating with your solar water heating system, which may prevent the solar panels from boosting your hot water.
Your boiler is operating normally and is currently working to provide heating to your home.
Your boiler is currently heating your hot water and is working exactly as it should.
Your boiler is pausing temporarily to prevent it from turning on and off too frequently while it redistributes heat around your home.
Your boiler is currently idle and is not reporting a fault, it is simply waiting for a signal from your thermostat to provide heating or hot water.
Your boiler has shut down because the water inside its internal loop has become hotter than the system is programmed to allow.
Your boiler has been accidentally switched into a specific testing mode used by engineers to check emissions, which is why it is ignoring your normal heating and hot water settings.
Your boiler has detected that the water temperature is rising far too quickly, likely because the system cannot move the heated water away fast enough.
Your boiler has detected that water is not circulating through the system quickly enough, causing a large temperature gap between the outgoing and incoming pipes.
Your boiler has detected that the internal fan responsible for clearing exhaust gases has failed to start correctly, so it has automatically shut down to keep your home safe.
Your boiler has stopped working because it cannot confirm that the internal fan is blowing air correctly to safely clear exhaust gases.
Your boiler has lost the connection to one of its internal temperature sensors, causing it to stop running as a safety precaution.
Your boiler has detected that it has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler is trying to start, but it cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is confused because it senses an internal signal that makes it think the flame is burning even when it is not, causing it to shut down for safety.
Your boiler is struggling to stay lit and has cut itself off as a safety precaution because it cannot maintain a stable flame.
Your boiler has been instructed to turn off by an external device, such as a smart thermostat, weather sensor, or a specialized security system.
Your boiler's computer is having trouble recognising its own internal settings and components, which means it has safely shut itself down to prevent further issues.
Your boiler is struggling to communicate with the part that controls the gas supply, meaning it cannot ignite to provide heat or hot water.
Your boiler's internal computer system is having a communication error because it cannot recognise the current configuration of the internal electrical parts.
Your boiler has detected an internal communication error and has safely shut itself down to prevent potential damage.
Your boiler's main computer control panel has encountered an internal error and cannot communicate with the rest of the unit to heat your home.
Your boiler has lost communication with a temperature sensor because of a loose wire or a faulty internal component.
Your boiler has lost communication with its internal temperature sensor, preventing it from heating your water safely.
Your boiler has detected an issue with its internal electronic control system that prevents it from operating safely.
Your boiler's internal computer has encountered a critical communication error and needs to be reset or inspected by a professional.
Your boiler's computer has detected an internal communication error and has safely shut down to prevent incorrect operation.
Your boiler's main computer control panel is experiencing a software or hardware error and needs professional attention to reset or replace.
The internal computer board of your boiler is experiencing a communication or processing error, which has caused the system to shut down for safety.
Your boiler has experienced an internal electronics failure that is preventing it from starting up safely.
Your boiler's computer system has encountered an internal glitch and requires a reset or professional check to function correctly again.
Your boiler's computer system has encountered a internal software glitch that is preventing it from operating correctly.
Your boiler's computer is having trouble reading its internal software, which has caused it to stop working to ensure safety.
The boiler's internal computer is experiencing a memory error and needs to be restarted to clear the fault.
Your boiler's internal computer is experiencing a memory error, preventing it from starting up correctly.
Your boiler's internal computer is experiencing a memory error, which means it cannot safely control its own operation and has shut down to protect itself.
Your boiler's internal computer is experiencing a temporary communication error or software glitch that is preventing it from running properly.
Your boiler's main control computer is experiencing a communication error, meaning it has safely shut down to prevent incorrect operation.
Your boiler's main computer system has encountered an internal error and needs a reset to try and regain control.
Your boiler has detected an internal communication error with its main control system, meaning it cannot process the signals needed to operate safely.
Your boiler's computer system has encountered a logic error and needs to be restarted to resume normal operation.
Your boiler's computer has encountered a memory or communication error and is unable to follow its normal startup routine.
Your boiler has detected an issue with the way it is managing its air supply, which is necessary for safe and efficient operation.
Your boiler is struggling because it is producing more heat than your home is currently ready to absorb, which usually happens when the internal flow of water is blocked or restricted.
Your boiler has flagged an internal check of its electrical safety switches which has not been cleared automatically.
Your boiler has detected that the flame inside is not staying lit as it should, so it has turned itself off to stay safe.
Your boiler is simply performing its routine self-check and starting up, so no action is required from you.
Your boiler has detected that the internal components responsible for burning fuel and venting gases are not communicating properly, so it has safely shut itself down to prevent unsafe operation.
Your boiler has become stuck in a technical testing mode used by engineers during maintenance and cannot currently heat your home or water.
Your boiler is not detecting enough water flow or pressure to push warmth into your radiators and taps.
Your boiler is currently going through its normal ignition process to start heating your home.
Your boiler has detected an issue with the internal valve that mixes gas and air, which is preventing it from firing up correctly.
Your boiler has stopped working because the water returning from your radiators is too hot, suggesting it is not circulating through the system correctly.
Your boiler is temporarily pausing between heat cycles to protect itself and ensure efficient operation, which is a normal behavior rather than a breakdown.
Your boiler has detected that it is still sensing a flame even though it has tried to shut off the gas supply, which could indicate a safety issue with internal components.
Your boiler's internal computer is having trouble communicating with its controls, which means the system has stopped working as a safety precaution.
Your boiler has experienced a temporary electricity supply flicker or power cut, causing the system to briefly lose its signal.
Your boiler is heating its internal water much faster than it is able to circulate, causing the system to automatically shut down to prevent damage.
Your boiler is switching itself off because the water inside is heating up much faster than it safely should during hot water production.
Your boiler has stopped because it thinks the water returning from your radiators is hotter than the water it just sent out, which usually means a sensor is confused or water isn't flowing correctly.
Your boiler has detected an electrical fault in a temperature sensor, which is preventing it from safely heating your home or water.
Your boiler has lost the signal from the sensor that monitors the temperature of the water flowing through your heating system, so it has shut down as a precaution to prevent overheating.
Your boiler has detected an internal safety system failure and has stopped working to prevent any potential risks.
Your boiler has detected an internal safety fault during its automatic startup checks and has locked itself out to prevent unsafe operation.
Your boiler is failing to operate because the electricity supply reaching it is not strong enough to meet its requirements.
Your boiler is currently running a brief automatic safety check to clear out any leftover air or gases before attempting to ignite the flame.
Your boiler is simply performing a routine, brief maintenance spin to prevent its internal pump from getting stuck while not in use.
Your boiler's internal computer has lost its 'identity' because the small data chip that tells it how to operate correctly is either faulty or not plugged in properly.
Your boiler's computer is having trouble recognising its internal configuration or has suffered a hardware failure, meaning it cannot operate safely.
Your boiler has detected that the flame sensor is still picking up a signal even when it should be off, meaning the system cannot safety-verify the combustion process.
Your boiler has detected an internal issue where a component responsible for controlling the fuel supply is failing to shut off correctly.
Your boiler has detected that a small valve responsible for controlling the fuel supply is not closing properly, which means it cannot operate safely.
Your boiler is currently running a self-diagnostic check to ensure its internal temperature sensors are reading accurately.
Your boiler has detected a failure within its internal electronic brain, meaning it has safely shut itself down to prevent any unsafe operation.
Your boiler is currently unable to provide hot water, meaning you will likely have cold taps and a cold shower until the fault is corrected.
Your boiler is struggling to accurately monitor the temperature of the water circulating through your heating system, which means it may not heat your radiators or hot water as efficiently as it should.
Your boiler's electronic controller is temporarily unable to 'talk' to the main system, causing the unit to stop working as a safety precaution.
Your boiler has lost its internal connection to the smart controls or sensors, meaning the main computer cannot talk to the rest of the system.
Your boiler has detected that it is running at the absolute limit of its burning capacity and has safely shut itself down to prevent overheating or component damage.
Your boiler is struggling to detect a flame, which means it cannot safely ignite to provide you with heating or hot water.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Your boiler is simply reminding you that its annual scheduled maintenance check is now due to keep it running safely and efficiently.
Your boiler has identified that the internal water pump does not match the settings configured in the system's software.
Your boiler is struggling to accurately measure the temperature of the water being heated for your taps and shower, so it has stopped heating it to prevent overheating.
Your boiler has been running for a very long time without a break and has automatically paused to prevent overheating or excessive wear.
Your boiler is struggling to accurately read how hot the water returning from your radiators is, which prevents it from heating your home properly.
Your boiler has lost the connection to a sensor responsible for monitoring the temperature of your hot water supply, which may affect its ability to keep hot water ready for instant use.
Your boiler has lost the signal from the weather sensor outside, so it is now running in a basic mode to ensure you still have heating and hot water.
Your boiler is currently unable to accurately read the water pressure inside the system because the sensor responsible for this signal has stopped working or has lost its connection.
Your boiler is struggling because it has lost the signal from a sensor that tells it how to react to external conditions or combustion efficiency.
Your boiler has detected a faulty signal from its internal temperature reading component, causing the system to stop working as a safety precaution.
Your boiler has lost communication with a key temperature reader, meaning it cannot accurately monitor your heating system and will shut down for safety.
Your boiler has detected an electrical fault with an internal temperature monitoring component, which will prevent it from heating your home or water safely.
Your boiler has lost its connection to a sensor responsible for monitoring its internal temperature, causing it to shut down to prevent overheating.
Your boiler's internal computer has encountered a software or communication error and needs to perform a reset to clear the system.
Your boiler has detected an internal software or communication error that is preventing it from operating safely.
Your boiler's main computer control panel is experiencing a communication or processing error, preventing the system from operating safely.
Your boiler's main control unit has detected an internal electronic error and has shut down for safety to prevent further issues.
Your boiler is struggling to breathe properly because its flue pipe, which vents gases outside, may be blocked or disconnected.
Your boiler has failed its internal self-adjustment process, meaning it cannot safely set the correct balance of gas and air to function correctly.
Your boiler has failed to ignite during a setup process, meaning it cannot start the burner to provide heating or hot water.
Your boiler is struggling to detect the flame needed to heat your home during its automatic adjustment process and has temporarily shut itself down for safety.
Your boiler's internal electronic brains have lost their connection, meaning the system cannot safely ignite to provide heating or hot water.
Your boiler's internal fan is stuck running longer than it should after it has finished heating your home or water.
Your boiler has detected that gas is still flowing when it should be shut off, which is a safety concern that prevents the system from operating.
Your boiler has attempted to start but failed to detect a flame, meaning it cannot produce heat or hot water.
Your boiler has detected an issue with the way it is burning fuel, so it has safely shut itself down to prevent any unsafe operation.
Your boiler is struggling to detect the flame correctly and will stop working to keep your home safe.
Your boiler is currently stuck in a technical testing mode used by engineers during setup and is not operating normally to heat your home.
Your boiler has detected an internal computer error that is preventing it from operating correctly.
Your boiler has detected an issue with the valve that regulates its gas supply, which prevents it from safely firing up.
Your boiler's control system is unable to communicate with the part that regulates gas flow, meaning it cannot safely ignite to provide heating or hot water.
Your boiler is struggling to confirm it is receiving the correct amount of gas to operate safely and has shut down to protect itself.
Your boiler has detected an issue with the valve that controls the gas flow, and for your safety, it has shut itself down to prevent it from operating incorrectly.
Your boiler has stopped because it cannot maintain a steady flame, meaning you currently have no heating or hot water.
Your boiler's computer is experiencing a temporary software glitch and cannot communicate correctly with its internal systems.
Your boiler's internal computer is experiencing a communication error or electronic fault, causing it to shut down for safety.
Your boiler's internal computer is experiencing a critical processing error and has stopped functioning to protect itself from unpredictable operation.
Your boiler's internal computer is experiencing a communication error, which has caused it to shut down to prevent potential damage.
Your boiler is struggling because it is not receiving the correct amount of electrical power, which is stopping it from operating normally.
Your boiler is struggling to pump water around your heating system fast enough, so it has turned itself off to prevent overheating.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning correctly, so it has shut down to keep your home safe.
Your boiler is struggling because the electrical power reaching it from your home's main supply has dropped below the required level.
Your boiler is rapidly turning itself on and off because it is struggling to move heat away into your radiators effectively, often due to a blockage or a closed valve.
Your boiler's computer is struggling to identify the specific configuration chip meant for your model, causing it to shut down for safety.
Your boiler's computer is struggling to identify the specific electronic card that tells it how to run your heating system.
Your boiler is attempting to start but is failing to stay lit because it cannot detect a flame, which has caused it to shut down for safety.
Your boiler is trying to start but is failing to detect a flame, which means your heating and hot water have stopped working.
Your boiler is attempting to light but is failing to detect a flame, meaning it cannot produce heat or hot water.
Your boiler is repeatedly failing to keep its internal flame lit, so it has stopped working to keep your home safe.
Your boiler is having trouble confirming that the burner has lit safely, so it has stopped working to keep your home safe.
Your boiler is failing to light the internal burner properly during low-power operation, meaning it cannot provide you with heating or hot water safely.
Your boiler is attempting to start up but is failing to maintain the flame needed to heat your home and water.
Your boiler's computer settings do not match the way your heating system has been physically installed, preventing it from functioning correctly.
Your boiler's internal settings are currently mismatched with your home heating setup, preventing it from functioning correctly.
Your boiler's main computer has encountered an internal technical glitch that is preventing it from firing up safely.
Your boiler's computer is having trouble communicating internally, which has caused the system to shut down for safety.
Your boiler's main computer control panel is experiencing an internal error and cannot communicate with the system, meaning the boiler has shut down for safety.
Your boiler's main control computer is experiencing a communication or processing error, preventing it from operating safely.
Your boiler has stopped working because it cannot confirm that the internal fan, which is essential for safely exhausting waste gases, is spinning correctly.
Your boiler has identified an issue with the internal air circulation system, which is preventing it from lighting safely.
Your boiler has detected data from its internal temperature sensors that falls outside the expected range, prompting it to shut down for safety.
Your boiler is struggling to pump water around the system effectively, which is causing it to stop heating to prevent damage.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has shut down because the water inside it is heating up much faster than it can be moved around your system.
Your boiler has detected that the water temperature is fluctuating unevenly inside the unit, forcing it to shut down to prevent damage.
Your boiler has detected that the water pressure in your heating system is dropping much faster than it should, which usually points to a leak somewhere in your radiators, pipes, or the boiler itself.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Your boiler is struggling because the electricity supply coming from your mains is weaker than required to operate safely.
Your boiler's internal computer is experiencing a communication fault, meaning it cannot safely operate the heating or hot water until reset or repaired.
Your boiler's computer has hit an unexpected internal error which is preventing it from running safely and effectively.
Your boiler has experienced an internal software or communication error that has caused it to lock down for safety.
Your boiler has detected an internal safety issue and has shut itself down to prevent damage, meaning you currently have no heating or hot water.
Your boiler is having trouble communicating with its wall-mounted thermostat control panel, likely due to a loose wire or a fault in the control unit itself.
Your boiler is working exactly as it should and there is nothing to worry about.
Your boiler has lost all power and is currently completely shut down, meaning you will not have any heating or hot water.
Your boiler has detected that the water pump responsible for circulating heat has stopped working, meaning the unit will currently refuse to provide hot water or heating.
BoilerFaultCodes