291 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal computer is failing to recognize a vital communication chip, which is preventing the heating system from operating safely.
Your boiler has automatically shut down because the water inside it has become dangerously hot and exceeded its safe operating temperature.
Your boiler has detected an issue with the internal fan that pushes exhaust gases out, meaning it has safely shut itself down to prevent unsafe operation.
Your boiler has experienced a power interruption following an earlier internal safety shutdown, meaning it has now locked itself to prevent operation until a reset is performed.
Your boiler has detected an internal computer error that has caused it to stop working for safety reasons.
Your boiler has encountered an internal technical error that requires a professional to investigate and reset the system safely.
Your boiler has lost the connection to the temperature control panel on your wall, so it does not know the room temperature and has stopped heating.
Your boiler's wall-mounted heating controller is having trouble communicating with the temperature sensor, which may prevent your heating from turning on correctly.
Your boiler is struggling to detect the outdoor temperature because the external sensor is either disconnected or faulty, but your heating and hot water should still work normally.
Your boiler has detected that an electronic component inside the unit is either mismatched, loose, or failing to communicate correctly with the main control board.
Your boiler's internal computer is struggling to identify its own configuration settings, which has caused it to stop working for your safety.
Your boiler's computer has detected that a setting switch has been moved or become misaligned since it was first set up, causing it to stop operating for safety.
Your boiler has detected that an internal sensor inside the casing has been moved or is not making proper contact, preventing it from heating your home safely.
Your boiler is struggling to heat your hot water tank to the high temperature required to keep the water supply hygienic.
Your boiler has developed a communication failure between its main internal control modules, causing it to stop operating correctly.
Your boiler has detected a faulty connection to a temperature sensor, which is preventing it from safely monitoring the water temperature.
Your boiler has lost communication with a sensor that monitors the internal water temperature, preventing it from heating your home or water safely.
Your boiler is having trouble communicating with the heat sensor in your hot water cylinder, which may prevent your water from heating up correctly.
Your boiler is having trouble communicating with the heat sensor in your solar hot water tank, meaning it may struggle to efficiently use solar energy to heat your water.
Your boiler is having a communication problem with an attached thermostat or controller that it does not recognise.
Your boiler is struggling to communicate with its external controls, like your thermostat or timer, causing the system to stop functioning correctly.
Your boiler is struggling to communicate correctly with a connected accessory, such as your thermostat or programmer, causing the system to stop working properly.
Your boiler's solar water heating system is struggling because the water-circulating pump is physically stuck and unable to move fluid around the system.
Your boiler is having trouble communicating with the sensor that measures the temperature of your hot water cylinder.
Your boiler is confused because it is receiving an incorrect signal from a temperature sensor, which is preventing it from heating your water or home properly.
Your boiler has detected that two of its internal temperature monitoring cables have become swapped or disconnected, meaning it cannot accurately read how hot the water is.
Your boiler is receiving an unusual signal from a temperature sensor, which has caused it to stop working for safety reasons.
Your boiler's solar water heating system is currently unable to circulate fluid because the pump responsible for moving that heat is stuck.
Your boiler is confused because it detects a temperature sensor in the wrong location, preventing it from heating your water correctly.
Your boiler has detected a communication error with a sensor responsible for monitoring water temperatures, causing it to shut down to prevent potential damage.
Your boiler has detected a new smart control or accessory and is currently struggling to communicate with it, meaning it needs help to recognize the new connection.
Your boiler has detected a new smart accessory or controller has been connected to its communication system and needs to be formally recognised.
Your boiler has stopped working because it cannot correctly detect the temperature of the water being circulated through your heating system.
Your boiler is failing to communicate with its internal control system, which means it cannot safely ignite or regulate your heating and hot water.
Your boiler's communication system has encountered a major internal error, meaning the main control board can no longer effectively talk to the heating components.
Your boiler has lost the water pressure needed to run, meaning it has switched off to protect itself until the system is topped up.
Your boiler has detected an issue with the ventilation system that clears exhaust gases, so it has safely shut down to prevent any risk of fumes entering your home.
Your boiler has detected an issue with its internal airflow or ventilation system and has temporarily shut itself down to ensure your safety.
Your boiler has sensed that exhaust gases are not escaping properly and has shut down to prevent the buildup of dangerous fumes in your home.
Your boiler has detected that the water is not circulating properly, likely due to air trapped in the system or a blockage preventing smooth flow.
Your boiler has detected that the water leaving it is much hotter than the water returning, suggesting a blockage or a problem with how water is circulating around your heating system.
Your boiler has stopped working because the internal component responsible for pushing air through the system is failing to start.
Your boiler has stopped working because the internal fan, which is responsible for safely venting exhaust gases, is failing to start.
Your boiler has detected that the internal fan is spinning faster than it should, so it has safely shut down to prevent any risk.
Your boiler has detected that the internal exhaust fan is spinning faster than it should for safety reasons, so it has automatically shut down to prevent potential issues.
Your boiler is struggling to push out waste gases properly because its internal ventilation fan is not spinning fast enough.
Your boiler has detected that the internal fan responsible for moving air is not spinning fast enough, causing the system to stop working to ensure safety.
Your boiler is unable to clear out exhaust gases properly, so it has safely shut down to prevent any risk.
Your boiler is unable to safely move air through its system, so it has shut down to prevent any unsafe conditions.
Your boiler has detected that the water inside the system is getting much hotter than it should be and has shut itself down to prevent damage.
Your boiler has detected that the water inside the system is getting dangerously hot and has shut itself down to prevent damage.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage.
Your boiler has detected a faulty sensor reading, which has automatically shut the system down to prevent overheating.
Your boiler has detected an electrical fault with a safety component, causing it to shut down to prevent potential overheating.
Your boiler has detected a disconnected or faulty internal temperature sensor, so it has shut down as a precaution to prevent the system from overheating.
Your boiler has detected that a safety device is not plugged in correctly, causing it to shut down to prevent unsafe operation.
Your boiler has detected an electrical fault in the part that measures the movement of water, which means it has safely shut down to prevent damage.
Your boiler is failing to detect the flow of water because an internal sensor is malfunctioning, which means it has safely shut down to prevent damage.
Your boiler has lost the signal from the part that monitors water flow, meaning it cannot safely trigger the heating or hot water to turn on.
Your boiler has lost its connection to a sensor responsible for monitoring water movement, meaning it cannot safely start the heating or hot water process.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage or danger.
Your boiler has detected that it has become too hot and has automatically switched itself off to prevent any damage to the unit.
Your boiler has detected that the water temperature is moving through the system unevenly, causing it to shut down to prevent damage.
Your boiler is trying to start but cannot detect a flame, so it has safely shut itself down to prevent gas from building up.
Your boiler is failing to ignite because it cannot detect a flame, meaning your heating and hot water will not work.
Your boiler has detected a signal that suggests it might still be running or has a sensor error before it has actually been told to start, so it has safely locked itself out to prevent a fault.
Your boiler has detected an internal sensor reading that suggests it might behave unexpectedly if it tries to light, so it has stopped itself as a safety precaution.
Your boiler has detected that the internal flame has gone out unexpectedly while it was trying to heat your water or home.
Your boiler has stopped because it cannot detect that the flame is lit, meaning it has safely shut down to prevent gas from building up.
Your boiler is failing to detect a flame, which has caused it to shut down for safety reasons to prevent unburnt gas from building up.
Your boiler has failed to ignite the gas safely and has shut itself down to prevent a potential hazard.
Your boiler has detected a brief loss of electricity or a dip in power, causing it to shut down temporarily.
Your boiler has detected a disruption in its electrical supply, which has caused it to temporarily shut down the system.
Your boiler has been turned off by an external safety device, such as a thermostat, a service switch, or a smart heating controller.
Your boiler's main computer brain is having a communication error, meaning it cannot properly control the heating or hot water system.
Your boiler's main control unit is failing to communicate properly, which has caused the system to shut down for safety.
Your boiler has lost its connection to the component that controls the gas supply, meaning it cannot ignite to provide heat or hot water.
Your boiler has stopped working because it cannot detect the internal connection needed to release gas to the burner.
Your boiler has detected that the internal fan is not switching off as it should, which can cause the system to stop working properly.
Your boiler's internal computer has encountered a critical system failure and can no longer safely control the unit.
Your boiler's central electronic computer has encountered a critical internal failure and is no longer able to operate safely or reliably.
Your boiler's internal computer has encountered a critical failure and is no longer able to safely operate or manage its core functions.
Your boiler's internal computer has detected a potential electronic malfunction and has shut itself down as a safety precaution.
Your boiler's internal computer has detected a potential communication error with its safety circuits and has shut down to prevent unsafe operation.
Your boiler's computer has detected an internal safety conflict, causing it to lock itself down to prevent potential operation errors.
Your boiler has detected a faulty connection to a temperature sensor that monitors the water returning to the system, causing it to stop working for your safety.
Your boiler has detected a faulty reading from a temperature sensor that monitors the water returning to the system, causing it to shut down for safety.
Your boiler has detected an incorrect electrical reading from a temperature sensor, which is preventing it from heating your water correctly.
Your boiler has lost the signal from one of its internal temperature sensors, meaning it cannot currently tell how hot the water returning to it is.
Your boiler has lost its connection to a temperature sensor and is unable to accurately measure the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler has lost the signal from one of its internal temperature sensors, causing it to shut down for safety.
Your boiler has detected an internal computer error that prevents it from starting safely, and it requires a professional engineer to reset or repair the main control board.
Your boiler has detected an internal software or electronic fault that prevents it from starting safely.
Your boiler's internal computer has encountered a critical error, meaning it can no longer safely control the system and will likely remain switched off.
Your boiler's main computer has detected a serious internal fault that requires a professional engineer to investigate.
Your boiler's main computer has encountered an internal fault and is unable to operate safely, meaning you currently have no heating or hot water.
Your boiler has detected a critical internal software or electronic communication error and has safely shut itself down to prevent potential damage.
Your boiler has detected an internal software or electronic control failure and has safely shut itself down to prevent further issues.
Your boiler is failing to ignite the flame reliably, meaning it cannot produce heating or hot water at the moment.
Your boiler is failing to ignite because it cannot detect a flame, likely due to a gas supply issue or a blockage in the ventilation system.
Your boiler is failing to light the internal flame, which has caused it to stop working to keep your home safe.
Your boiler has detected an internal software or communication error that is preventing it from operating safely.
Your boiler has detected an internal computer error that prevents it from starting safely.
Your boiler has detected that the air supply needed for safe combustion has been interrupted while it was running, causing it to shut down for safety.
Your boiler has detected that air cannot flow correctly through the system, so it has safely shut down to prevent any risk.
Your boiler has switched itself off because it has detected an issue with the air or exhaust flow required to safely burn gas.
Your boiler has temporarily stopped operating because it has detected an issue with the rate at which heat is moving through the system.
Your boiler is struggling to detect water movement, which suggests it cannot properly circulate heat to your radiators or taps.
Your boiler is struggling to confirm that water is successfully moving through the system, so it has safely shut down to prevent damage.
Your boiler is struggling to detect water movement, which prevents it from heating up safely.
Your boiler's computer system has detected an internal processing error and has shut down to prevent any unsafe operation.
Your boiler's computer has experienced a momentary freeze or internal processing error and needs to be restarted to resume normal operation.
Your boiler's computer has become unresponsive and needs to restart itself to try and clear a temporary internal processing error.
Your boiler is struggling to light because it is detecting an issue with the ignition process, causing it to lock itself out for safety.
Your boiler is failing to light the flame or stay lit, causing it to stop trying after several unsuccessful attempts.
Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has detected that the water temperature is changing too drastically between two different points, causing it to shut down to prevent potential damage.
Your boiler has detected that water is heating up or moving through the system unevenly, leading it to shut down to prevent potential overheating.
Your boiler has detected that the water is getting much hotter in one part of the system than another, so it has safely shut itself down to prevent overheating.
Your boiler has detected an internal electronic error that is preventing it from starting up correctly.
Your boiler's computer is experiencing a major internal communication failure and cannot safely continue normal operation.
Your boiler's computer has encountered a critical internal processing error and has shut itself down as a safety precaution.
Your boiler has detected that the internal fan was running when it should have been switched off, suggesting a potential communication issue with the control board.
Your boiler has detected that the water inside it has become dangerously hot and has temporarily shut itself down to prevent damage.
Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage.
Your boiler has detected that the water inside has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has detected that it is getting too hot and has automatically paused to prevent damage, but it requires professional attention to identify why it isn't cooling down properly.
Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage.
Your boiler has detected that the water inside it has become dangerously hot and has automatically shut down to prevent damage or safety issues.
Your boiler has detected a failure during its internal safety startup check and will not fire up to prevent any potential risks.
Your boiler is struggling because it cannot verify that its internal safety sensors are working correctly, causing it to shut down to prevent damage.
Your boiler's computer has detected an internal communication error between its sensors, meaning it cannot safely regulate its temperature and has shut down to prevent damage.
Your boiler's computer is struggling to read internal sensor data correctly, which prevents it from operating safely.
Your boiler's computer is having trouble reading its internal sensors, which is causing it to shut down for safety because it cannot accurately monitor temperatures.
Your boiler's computer is struggling to read internal sensor data correctly, which prevents it from operating safely or consistently.
Your boiler is struggling to restart because it is having trouble clearing out gases from its internal safety cycle.
Your boiler has detected an internal timing issue and is preventing itself from firing to protect the system.
Your boiler has detected that it is restarting too frequently and is temporarily holding off to protect its internal parts from excessive wear.
Your boiler is struggling because the internal water pump is either jammed or air is trapped inside the system, preventing water from circulating properly.
Your boiler's water circulation pump is struggling to move water, often because it is jammed or trapped air is blocking the flow.
Your boiler is struggling because the internal pump that moves water around your heaters has seized or is struggling to push water through the pipes.
Your boiler has detected that the internal water pump is not running as expected, which prevents hot water from circulating through your radiators or taps.
Your boiler has detected that the water pump is not running as expected, which means it cannot circulate heat from the boiler to your radiators or taps.
Your boiler has detected that the water pump responsible for circulating heat is not responding, which is preventing your heating and hot water from working.
Your boiler has detected that the water returning to it is dangerously hot and has temporarily switched itself off to prevent system damage.
Your boiler has detected that the water returning to it is much too hot, so it has safely shut itself down to prevent damage.
Your boiler has detected that the water returning to it is dangerously hot, causing it to shut down to prevent damage.
Your boiler has detected that the water returning from your radiators is hotter than it should be, causing the system to temporarily shut down to prevent overheating.
Your boiler is detecting that the water returning from your radiators is hotter than it should be, causing it to pause heating to prevent overheating.
Your boiler has detected that the water returning from your radiators and pipes is hotter than it should be, suggesting the system is struggling to regulate its temperature.
Your boiler has detected an issue with the sensor that confirms the burner flame is lit, preventing it from safely starting up.
Your boiler has detected an electrical problem with the sensor that checks if the flame is burning correctly, so it has shut down as a safety precaution.
Your boiler has detected an electrical fault in the part responsible for sensing the flame, which prevents it from safely igniting.
Your boiler's internal computer has lost contact with the sensor that measures how much water is inside the system, so it has shut down to prevent damage.
Your boiler is struggling to detect the water pressure inside the system because the sensor is either unplugged or has a faulty electrical connection.
Your boiler is struggling to read its own internal water levels because there is a loose wire or a faulty connection involving the sensor that checks the system pressure.
Your boiler has lost its connection to the sensor that monitors internal water pressure, so it has safely shut down to prevent potential damage.
Your boiler's internal sensor that detects water pressure has lost its connection or has developed a wiring fault, preventing it from knowing if the system pressure is safe to operate.
Your boiler's internal computer has lost its connection to the component that monitors water pressure, so it has safely shut down to prevent damage.
Your boiler's electronic control system is experiencing an internal error, preventing it from accurately reading its own internal settings.
Your boiler's internal computer has flagged a failure in its ability to read data from electronic sensors, preventing it from operating safely.
Your boiler’s internal computer is struggling to read data from its sensors, which has caused it to stop working to keep your home safe.
Your boiler is temporarily pausing to prevent damage because it has been switching on and off too frequently for your hot water.
Your boiler has detected a signal that it is still burning gas even though it has already switched itself off, which is a safety concern that requires an immediate check.
Your boiler is continuing to detect a flame even after it should have turned off, indicating a safety sensor or valve fault.
Your boiler has detected a flame signal even though it has commanded the burner to turn off, indicating it cannot safely confirm the fire has gone out.
Your boiler's water pump is failing to move water around the system, meaning your heating and hot water will not function.
Your boiler has detected that the exhaust gases are getting too hot, so it has safely shut itself down to prevent any damage.
Your boiler has detected that the exhaust gases leaving the unit are hotter than they should be and has shut down to prevent potential damage.
Your boiler has detected that it is running at a higher temperature than it should be and has shut itself down as a safety precaution to prevent damage.
Your boiler has detected an electrical fault with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety.
Your boiler has detected a faulty connection in the system that checks the temperature of the gases leaving your flue, causing it to shut down for safety.
Your boiler has detected an electrical fault with the internal sensor that monitors the safety of the exhaust gasses, causing it to automatically shut down to prevent unsafe operation.
Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the gases leaving your flue.
Your boiler has detected that a key safety sensor measuring temperature inside the flue is currently not sending a signal, causing the boiler to shut down to prevent overheating.
Your boiler has lost its connection to a safety sensor that monitors the temperature of burned gases, so it has safely shut down to prevent potential overheating.
Your boiler's internal computer parts are struggling to talk to each other, causing the system to stop working as a precaution.
Your boiler's internal control computer has lost its connection, preventing it from processing commands and operating your heating or hot water correctly.
Your boiler has lost the ability for its internal parts to 'talk' to each other, so it has shut down as a precaution to prevent operating incorrectly.
Your boiler is struggling to accurately measure the temperature of the water it is heating for your taps and shower because a sensor is loose or disconnected.
Your boiler is having trouble sensing the temperature of your hot water cylinder, which means it may struggle to provide consistent hot water.
Your boiler is not starting because the button used to restart the system is stuck or experiencing an electrical fault.
Your boiler's main computer control panel has detected an internal communication failure and has locked itself down for safety.
Your boiler is unable to detect that water is moving through the system, so it has stopped working to protect itself from overheating.
Your boiler is struggling to detect the movement of water needed to heat your home, which has caused it to stop working for safety reasons.
Your boiler has detected that the water inside isn't moving correctly, so it has shut down to prevent damage to its internal parts.
Your boiler has automatically shut down because internal parts have become dangerously hot, likely due to a lack of water flow.
Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage or safety issues.
Your boiler has detected that it is overheating significantly and has shut itself down to prevent damage.
Your boiler is temporarily preventing itself from firing up because it cannot detect water moving through the heating system as expected.
Your boiler has repeatedly tried to start but failed to detect water movement, so it has locked itself out to prevent internal damage.
Your boiler is struggling to keep the water moving properly, so it keeps turning itself off and on to protect itself from overheating.
Your boiler is repeatedly trying to start up its flame but failing to detect that water is circulating through the system, causing it to lock itself to prevent damage.
Your boiler is shutting down because the water inside is heating up much faster than it can be moved around your home's radiators.
Your boiler is overheating because it cannot move the hot water away from the heat exchanger quickly enough.
Your boiler is overheating because the water inside cannot circulate fast enough to move the heat away, so the system has safely shut itself down to prevent damage.
Your boiler is overheating while trying to heat your water and has switched itself off as a safety precaution.
Your boiler is struggling to process the heat it is generating, causing the water temperature to climb much faster than it should.
Your boiler has detected that the water inside is heating up much faster than it is supposed to, which often means there is not enough water flowing through the system to carry the heat away properly.
Your boiler has detected that the exhaust gases are getting too hot while the water inside the heating system is staying cold, suggesting a problem with how the boiler transfers heat.
Your boiler has detected that the exhaust gases are getting hotter than the water it is actually heating, which suggests a blockage or a faulty temperature sensor.
Your boiler has detected that the exhaust gases are becoming dangerously hot while the water it is meant to be heating remains cold, forcing it to shut down to prevent damage or overheating.
Your boiler has detected that the exhaust gases are becoming dangerously hot while the water inside the unit remains cold, suggesting a blockage or a failure in the heat transfer process.
Your boiler has detected that the exhaust gases are getting much hotter than the water it is trying to heat, suggesting an internal circulation issue.
Your boiler has detected that the exhaust gases are heating up abnormally while the water inside the system remains cold, suggesting a blockage or a failure in how the boiler transfers heat.
Your boiler has started up but cannot detect the water circulating through the system, meaning it is currently unable to heat your home or provide hot water.
Your boiler has detected that the water inside the system is not getting hotter after the flame lights up, so it has safely shut itself down.
Your boiler has detected that no heat is being transferred into your radiators or hot water pipes even though the system is trying to fire up.
Your boiler is overheating because the temperature of the gases escaping through the flue is rising much faster than it should, causing the system to shut down for safety.
Your boiler has detected that the temperature of the gases leaving the unit is rising too quickly, so it has safely shut itself down to prevent overheating.
Your boiler has detected that the temperature of the exhaust fumes is rising too quickly, so it has shut itself down to prevent damage or overheating.
Your boiler has detected that the water returning from your radiators is hotter than the water leaving the boiler, which is physically impossible and indicates a sensor error.
Your boiler has detected that hot water is flowing in the wrong direction or returning too hot, suggesting a blockage or a pump issue that is preventing the system from heating your home properly.
Your boiler has detected that hot water is flowing back into the system in the wrong direction or at an incorrect temperature, preventing it from heating your home properly.
Your boiler has detected that the water inside the system is becoming dangerously hot, so it has safely shut itself down to prevent overheating.
Your boiler has detected that the water inside the system is becoming dangerously hot and has shut itself down to prevent overheating.
Your boiler has detected that the water inside the system is getting much hotter than it should be, so it has shut down to prevent damage or overheating.
Your boiler is struggling because it cannot move the hot water away from the burner fast enough, suggesting a blockage or a failure in the internal pump system.
Your boiler has detected that it is heating up or cooling down much faster than expected while running at its lowest setting, which typically indicates a blockage or a failure in how water is flowing through the system.
Your boiler is struggling to circulate water effectively, as it senses a significant temperature difference between the water leaving and returning to the unit despite running at its lowest power.
Your boiler's sensor is incorrectly reading the flow of water, which is preventing it from safely starting up your heating or hot water.
Your boiler has detected an electrical fault with the sensor that tracks the flow of water, meaning it cannot safely start your heating or hot water.
Your boiler is failing to detect the flow of water because of a faulty electrical connection or sensor, which prevents it from providing heating or hot water.
Your boiler has lost the signal from the sensor that monitors the flow of water, meaning it has safely shut down because it cannot confirm water is moving through the system.
The boiler's digital memory has lost the settings that tell it how much pressure it should maintain, causing it to stop working for safety reasons.
Your boiler has detected that the water coming out of your hot tap is hotter than it should be, so it has safely shut down to prevent scalding.
Your boiler has detected an issue with the internal safety seal of the gas supply system and has shut down to prevent any unsafe operation.
Your boiler has detected an internal safety issue with the gas control valve, meaning it cannot confirm that the gas supply is shutting off correctly when the boiler stops.
Your boiler has detected that a safety valve responsible for controlling gas flow is not closing correctly, so it has safely shut itself down to prevent a potential gas leak.
Your boiler has detected a safety concern with its internal gas control system and has shut itself down to prevent any risk.
Your boiler has detected a potential issue with its internal gas supply system during its safety self-check, meaning it will remain locked out to prevent unsafe operation.
Your boiler has detected an internal safety issue with the gas control mechanism and has automatically shut down to prevent the fuel supply from operating incorrectly.
Your boiler has detected that it is overheating repeatedly and has locked itself down for safety to prevent damage.
Your boiler has detected that it is overheating repeatedly and has locked itself down for safety to prevent damage.
Your boiler has detected that it is getting too hot too often and has safely locked itself to prevent internal damage.
Your boiler has detected that the flame is repeatedly going out unexpectedly, so it has locked itself for safety reasons.
Your boiler has repeatedly failed to maintain a flame and has locked itself down for safety reasons to prevent gas from building up.
Your boiler has detected repeated issues with maintaining its flame during operation, so it has locked itself for safety to ensure it does not attempt to fire incorrectly.
Your boiler is having trouble reading the temperature of the incoming cold water, which may prevent it from providing consistent hot water.
Your boiler is having trouble reading the temperature of the incoming cold water, which may cause your hot water to fluctuate in temperature or not heat up correctly.
Your boiler is having trouble detecting the temperature of the incoming cold water supply due to a faulty electrical connection or sensor.
Your boiler is having trouble detecting the temperature of the water entering the system, which may affect how quickly your taps get hot.
Your boiler is having trouble detecting the temperature of the water entering the system, which prevents the hot water preheat feature from working correctly.
Your boiler is having trouble sensing the temperature of the incoming cold water, which may prevent the preheat function from working correctly.
Your boiler is receiving water that is already hotter than the temperature you have set for your taps and shower, which is confusing the system.
Your boiler has lost communication with the weather sensor outside your home, so it is using a default setting to ensure you still have heating and hot water.
Your boiler is struggling to detect the outside temperature, meaning it cannot automatically adjust your heating settings based on the weather.
Your boiler is struggling because it cannot read the temperature outside, so it is using default settings to keep your home warm.
Your boiler is struggling to accurately measure the temperature of your hot water, which means it may fail to provide a consistent hot shower or tap supply.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, which means you may experience inconsistent hot water.
Your boiler is struggling to accurately measure the temperature of your hot water, which means it may fail to provide hot water to your taps or shower.
Your boiler is currently unable to provide hot water to your taps and showers.
Your boiler is struggling to accurately read its own internal water pressure, which means it has safely shut down to prevent potential damage.
Your boiler is struggling to move water because there is air trapped in the system or the water pressure has dropped too low.
Your boiler has detected that water is not circulating properly, likely because the system pressure is too low or there is trapped air preventing the pump from working correctly.
Your boiler has lost the ability to measure the temperature of your hot water properly, which usually means your taps will only run stone cold or may fluctuate wildly in temperature.
Your boiler has lost its connection with the thermostat, meaning they are no longer speaking to each other to control your heating.
Your boiler’s internal computer has lost contact with a small identification chip that tells it how to operate correctly.
Your boiler's internal computer has encountered a critical failure and can no longer control the heating system, meaning the unit will not operate.
Your boiler has detected that the internal fan responsible for clearing exhaust gases has stopped working, so it has safely shut itself down to prevent carbon monoxide buildup.
Your boiler has detected that the internal fan responsible for venting exhaust gases has stopped working, so it has safely shut itself down to prevent any unsafe operation.
Your boiler has detected an issue with its internal airflow system that may have caused it to shut down for safety.
Your boiler has detected that the internal exhaust fan has been running non-stop for a full day, which can lead to parts wearing out or overheating.
Your boiler has detected that the internal fan is spinning too fast, causing the system to shut down for safety.
Your boiler has switched itself off because it cannot pull enough air through to safely burn the gas, so it will not provide any heat or hot water.
Your boiler has detected a faulty reading from a temperature sensor, which is preventing it from heating your water properly.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water returning from your radiators due to a faulty sensor signal.
Your boiler has detected that the water temperature is changing too quickly or unevenly between different parts of the system, so it has safely shut itself down as a precaution.
Your boiler has detected that the water temperature is varying significantly between its internal sensors, causing it to shut down for safety.
Your boiler has detected a faulty internal temperature sensor, which means it cannot accurately measure how hot the water is and has stopped running for safety.
Your boiler has automatically shut down because it has overheated to a dangerous level, likely due to a circulation problem or a faulty internal sensor.
Your boiler is overheating because the water inside is heating up too quickly, causing the system to shut down temporarily for safety.
Your boiler has detected that it is dangerously hot and has automatically shut down to prevent damage or safety risks.
Your boiler has detected that the temperature of the exhaust gases leaving the unit is too high, so it has safely shut itself down to prevent damage.
Your boiler has stopped working because it cannot detect a flame, meaning there is likely a disruption to the gas supply or an issue with the ignition process.
Your boiler is trying to start but cannot detect a flame, so it has shut itself down as a safety precaution.
Your boiler has detected that the water temperature is rising far too quickly for the amount of gas being used, which suggests water is struggling to circulate properly.
Your boiler has detected that your radiators are not absorbing enough heat, or your water is struggling to circulate through the system correctly.
Your boiler's internal computer has encountered a critical electronic glitch that is preventing it from running safely.
Your boiler’s internal computer is experiencing a communication error and has safely shut down to prevent further damage.
Your boiler's computer has encountered an internal communication error and has safely shut itself down to prevent potential damage.
Your boiler thinks there is still a flame burning even though it has commanded the system to turn off, causing it to shut down for safety.
Your boiler has detected heat or a flame inside the unit before it has actually been told to start, so it has safely locked itself down to prevent a potential hazard.
Your boiler thinks it still sees a flame even though it has commanded the gas to turn off, which is a safety conflict.
Your boiler has detected a flame signal when it should be switched off, which means the safety system has locked out the unit to prevent it from operating until it is checked by a professional.
Your boiler has detected a potential issue with the internal gas valve, which prevents it from starting to ensure your home remains safe.
Your boiler has detected that a safety component responsible for gas control is not operating as expected, so it has shut itself down to ensure your safety.
Your boiler has detected an issue with the internal gas valve and has safely shut itself down to prevent any potential risks.
Your boiler's reset button has been pressed incorrectly or held down for too long, causing a temporary communication error.
Your boiler has detected a brief power cut or a loose electrical connection, causing it to momentarily lose its settings.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes