394 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
This boiler uses indicator light combinations
Note which lights are on, off, or flashing and at what speed. Match the combination to the cards below. Do not reset until you have noted the pattern. How to read fault codes →
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Your boiler has stopped working because it cannot light a flame, meaning you currently have no heating or hot water.
Your boiler is failing to light the flame, which means it cannot produce any heating or hot water for your home.
Your boiler has detected that the flame inside has unexpectedly gone out while it was trying to run.
Your boiler is failing to detect the gas supply component, meaning it cannot safely ignite to provide heating or hot water.
Your boiler is failing to light the burner, meaning it cannot produce heat or hot water.
Your boiler has detected a potential internal gas leak or a sensor fault that prevents it from starting safely to protect your home.
Your boiler has detected a failure in its internal safety checks during startup and has safely shut itself down to prevent any risk.
Your boiler has detected that it is running much too hot and has automatically shut down to prevent damage or dangerous overheating.
Your boiler has detected an internal overheating issue or a blocked exhaust and has shut itself off to prevent damage or safety hazards.
Your boiler has detected that the water returning to it is too hot, causing it to shut down to prevent damage to its internal parts.
Your boiler has switched itself off because moving water inside the unit has become dangerously hot.
Your boiler is currently running in a manual testing mode at its maximum power, which is likely a temporary setting used by an engineer during a service.
Your boiler has been manually set to run at its lowest possible power level, usually because a technician is performing a service or safety check.
Your boiler is temporarily running at its maximum power level, which is usually a normal setting used by engineers during testing or after a reset.
Your boiler is currently running at its maximum power level to provide hot water and this code is often just an operational status indicator rather than a breakdown.
Your boiler is struggling to pump water around your home correctly because it cannot find the right speed setting for your heating system.
Your boiler has detected that the internal pump is not rotating at the correct speed to circulate water through your heating system.
Your boiler's internal pump is detecting a communication error or is set to the wrong operating mode, meaning it cannot circulate water properly.
Your boiler has sensed that the water inside is getting too hot too quickly and has shut down as a safety precaution.
Your boiler is currently running an automated sequence to remove trapped air from the system, which typically occurs after you first turn the power on or restart the unit.
Your boiler is in a normal operating mode, likely a service mode or a temporary state where it is monitoring its internal temperature sensors.
Your boiler is taking a short, programmed rest to prevent itself from switching on and off too frequently, which helps protect the internal components from unnecessary wear.
Your boiler is heating up too quickly and has paused itself to prevent over-heating, which often suggests there is a problem with the water circulating through the system.
Your boiler is struggling to provide hot water because it is overheating and shutting down too quickly during its operation cycle.
Your boiler has detected an error while turning off the burner after you used your hot water taps, which may prevent it from firing up again.
Your boiler is performing a routine automatic cleaning and filling cycle of its internal drainage system, which is a normal process and not actually a fault.
Your boiler is simply reminding you that its annual service is now due, and it does not indicate a breakdown or a safety fault.
Your boiler's fan is running longer than it should after the heating has turned off, which is usually a sign of a communication error between internal components.
Your boiler has failed to ignite properly, meaning it cannot create a flame to provide heating or hot water.
Your boiler has detected an issue with the sensor that tracks the flow of hot water, which may cause your hot water to stay cold or run inconsistently.
Your boiler is having trouble communicating with the internal clock or plug-in timer, preventing it from knowing when to turn on.
Your boiler's internal computer has lost its identity because the memory chip is either loose or failing.
Your boiler's internal configuration chip has been disconnected or is not being recognised correctly by the control board.
Your boiler has detected an internal communication error between its electronic control components and is unable to start for safety reasons.
Your boiler has detected an internal electronics communication error, which has caused it to stop working for safety.
Your boiler's internal memory has encountered an error and has reverted to its factory default settings, meaning it needs reconfiguring to work with your heating system.
Your boiler has detected a flame when there shouldn't be one, which usually means a internal component is stuck or damaged.
Your boiler is currently resetting itself to its original factory settings, which is a normal process usually triggered during maintenance or setup.
Your boiler's control panel has been set to stay on permanently, which means it isn't following your usual heating schedule or thermostat settings.
Your boiler's fan is not spinning at the correct speed, which prevents the system from safely starting the combustion process.
Your boiler is displaying its current power level because a technician is likely testing the system or a specific testing mode has been left on.
Your boiler is failing to start because the internal fan is not spinning at the speed required to clear waste gases.
Your boiler is struggling to detect when you turn on a hot tap, meaning you might have inconsistent or no hot water.
Your boiler's internal pump is running longer than it should after the heating has switched off, which often indicates a communication error or a trapped signal.
Your boiler has stopped working because the internal pump that moves water around your heating system has become stuck or failed.
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 is currently operating normally and is in the middle of heating your radiators.
Your boiler is currently heating your hot water as normal, so this is just an informational status message rather than a fault.
Your boiler is temporarily waiting to restart to prevent unnecessary wear and tear on its internal parts.
Your boiler is currently in a temporary holding state while it waits for a signal from your thermostat or hot water tap to start heating.
Your boiler is temporarily pausing because the water inside it has already reached the temperature you requested.
Your boiler is struggling to clear the gases from your last attempt to heat up and is holding back until it can breathe properly.
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 is currently locked in a testing mode used by engineers to check the flue system, which prevents it from heating your home normally.
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 is shutting down because it detects that your heating water is heating up far too quickly, which usually points to a poor flow through the system.
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 fan, which is responsible for safely venting exhaust gases, is failing to start.
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 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 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 dangerously hot and has 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 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 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 failing to ignite because it cannot detect a flame, meaning your heating and hot water will not work.
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 has failed to ignite the gas safely and has shut itself down to prevent a potential hazard.
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 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 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 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 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 a serious internal computer error that prevents it from operating safely.
Your boiler has detected an internal computer error that prevents it from starting safely.
Your boiler has lost the ability to accurately measure the temperature of the water being heated for your taps and shower, so it has safely shut down to prevent overheating.
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 an internal software or electronic communication failure that prevents it from operating safely.
Your boiler has detected a serious internal system error that prevents it from operating safely.
Your boiler's reset button is either physically jammed or there is an electrical fault, preventing it from functioning correctly.
Your boiler has successfully lit the flame, but the water inside is not heating up as expected.
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 a critical internal electronic failure and requires an expert engineer to diagnose and resolve.
Your boiler has detected an internal software or electronic malfunction that prevents it from operating safely, requiring professional intervention.
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 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 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 has accidentally entered a special technician-only mode used for testing parts, which stops it from heating your home normally.
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 is currently resetting or performing its initial startup sequence, which typically happens when power is first restored after a shutdown.
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'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 airflow when it shouldn't be there, which has caused it to lock itself down as a safety precaution.
Your boiler has detected that the fan or exhaust system is operating incorrectly or persistently when it should be idle.
Your boiler has detected that it is still sensing a flame even when it should be turned off, which may indicate a build-up of residue or a sensitive sensor.
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 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'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 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 is currently going through its normal ignition sequence to fire up and provide heat or hot water.
Your boiler is currently checking its internal safety systems before it begins the ignition process to heat your home.
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 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 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 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'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 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 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 has stopped moving, meaning it cannot circulate heat to your radiators or taps.
Your boiler is struggling because there is air trapped inside the pump rather than water, which stops it from circulating heat effectively.
Your boiler is currently performing a normal operational cycle by heating both your radiators and your hot water tank at the same time.
Your boiler's internal control system is struggling to communicate with its main circuit board, which has caused the unit to stop functioning.
Your boiler's electronic control unit has identified an internal software or configuration error that has caused it to lock itself to prevent damage.
Your boiler's internal airflow fan is struggling to spin correctly, which is preventing it from safely operating.
Your boiler has detected an internal communication error between its main control components, causing it to shut down for safety.
Your boiler has lost power while trying to resolve a safety shutdown, which has confused its internal computer. This is usually triggered by a power cut or a loose connection.
Your boiler is struggling because it cannot detect enough water flowing through its system to safely produce heat.
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 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 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 has detected an issue during its internal safety check of the exhaust system and has stopped working to prevent unsafe operation.
Your boiler's internal computer is experiencing a communication error, meaning it has stopped operating safely to prevent further electrical issues.
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 currently unable to sense the temperature of your hot water, which means it has stopped providing hot water to your taps and showers.
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 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 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 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 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 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 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 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 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 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 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 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 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's computer has lost connection with the part that monitors the flow of water, meaning it cannot detect when you turn on the hot tap or heating.
Your boiler has lost its connection to the component that detects when water is flowing through the system, so it has shut down as a precaution to prevent overheating.
Your boiler has automatically locked itself out temporarily because it has been running non-stop for too long, but it will reset itself and start working again shortly.
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 is currently running an automated self-clearing process to remove trapped air from its internal system, which will finish on its own in about two minutes.
Your boiler is struggling to switch between heating your radiators and heating your hot water because a small internal component has become temporarily stuck.
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 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 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 is temporarily pausing your heating as a safety precaution because it is becoming too hot and needs a short moment to cool down.
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 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 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 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 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 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 confused because the wrong type of temperature sensor has been plugged into the system, meaning it can't accurately monitor your hot water cylinder.
The system has detected that the wrong type of temperature sensor has been installed for your solar heating circuit.
Your boiler has lost communication with the temperature sensor that monitors your hot water cylinder, meaning it may not know when to stop heating your water.
Your boiler has detected a fault with the solar collector temperature sensor, meaning it cannot correctly monitor heat coming from your solar panels.
Your boiler's internal temperature sensors have likely been plugged into the wrong sockets or have developed a wiring fault, meaning the system cannot accurately track how hot the water is.
Your boiler's solar heating sensor has detected an unusually high temperature or a technical fault, causing the system to stop as a precaution.
Your boiler’s solar hot water system hasn't reached the high temperature needed to properly disinfect the cylinder, often because a cleaning cycle was interrupted or a pump is struggling.
Your boiler's built-in solar water heating software has been activated, but the solar system hasn't been set up or configured correctly for use.
Your boiler's internal pump or a control valve has been accidentally switched to a manual setting and is no longer being controlled automatically by the boiler.
Your solar heating system is circulating liquid too quickly, which usually means a sensor is misreading or the pump speed needs adjusting.
Your solar heating system is not circulating fluid quickly enough between the roof panels and your boiler setup.
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's temperature sensor responsible for monitoring the hot water storage is faulty or has lost connection, meaning the system cannot safely heat your water.
Your boiler has lost communication with the safety sensor that prevents your underfloor heating system from getting too hot.
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 lost the signal from one of its internal temperature sensors, which prevents it from safely controlling your heating and hot water.
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 detected that the water inside it is getting much hotter than it should be and has shut down for safety.
Your boiler has detected that the water inside has become dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler has detected that the water returning to it is dangerously hot and has shut itself down to prevent damage or overheating.
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 is experiencing an internal communication error and has safely shut itself down to prevent any further issues.
Your boiler's computer is experiencing a critical internal glitch that is preventing it from operating safely.
Your boiler's computer is experiencing a internal communication error that is preventing it from starting up correctly.
Your boiler has detected an internal software or communication error that is preventing it from operating correctly.
Your boiler's computer has encountered an internal communication error and has safely shut itself down to prevent potential damage.
Your boiler's computer has encountered an internal communication error and has shut down to prevent incorrect operation.
Your boiler's computer is experiencing an internal processing error, meaning it has stopped working safely to prevent potential damage.
Your boiler's computer has encountered an internal technical glitch that is preventing it from operating correctly.
Your boiler has detected an internal computer error that is preventing it from starting up correctly.
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's main electronic brain has encountered a permanent internal fault and is no longer able to operate your heating or hot water safely.
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's internal computer has lost communication with its control components, meaning it cannot receive or send the signals needed to operate.
Your boiler's internal computer is having trouble communicating with an external control or smart thermostat connected to it.
Your boiler's computer brain has become confused and is no longer recognising its own internal components.
Your boiler's main control chip is not making a proper connection, meaning the 'brain' of the appliance cannot communicate correctly.
Your boiler's main control unit is confused because a small internal configuration plug has moved or is failing, causing the system to lock out for safety.
Your boiler's main control unit is having a communication breakdown with its internal safety components, meaning it cannot operate safely and has shut down.
Your boiler's internal memory has encountered a glitch, causing some of its important settings to reset themselves to the factory defaults.
Your boiler's internal computer has encountered a critical error and can no longer communicate with the heating controls, causing the system to stop working.
Your boiler is having trouble communicating with the temperature thermostat built into its control panel, which means it doesn't know how warm your home is.
Your boiler's built-in thermostat controls has developed an electrical fault and can no longer tell how warm your room is.
Your boiler has detected a new internal electronic component or communication device and requires a manual reset to confirm and sync the system.
Your boiler has detected a change in its internal electronic communication system or a new part, and it needs to be officially acknowledged before it will start again.
Your hot water tank has overheated and a safety switch has shut the system down to prevent damage.
Your boiler's internal computer has lost communication with a central safety component or an external controller, causing the system to shut down for safety.
Your boiler has lost communication with its internal electronic controls or a safety switch has triggered to prevent overheating.
Your boiler's computer system has detected a change in its connected parts or settings and needs to be told how to recognize them again.
Your boiler's computer is confused because it thinks a new component has been plugged in or a setting has changed, and it needs to be told how to work with the updated system.
Your boiler's computer is confused because it has detected a change in its connected control components and needs to be told how to work with them again.
Your boiler is having trouble communicating with an external control or thermostat that isn't compatible with it.
Your boiler's internal computer has lost communication with its connected hot water or smart control components due to a settings mismatch.
Your boiler's internal computer is having trouble communicating with an external plug-in control or a hot water cylinder component.
Your boiler has lost communication with its outdoor weather sensor, meaning it cannot automatically adjust your heating based on the temperature outside.
Your boiler's internal computer is trying to communicate with a part or an external controller that it can no longer find or recognize.
Your boiler's computer and its remote control are having trouble speaking the same language, causing the system to stop working correctly.
Your boiler's internal computer has lost communication with one of its key control modules, meaning it cannot save or follow its programmed settings.
Your boiler is having trouble 'talking' to its internal controls or external thermostat, meaning it cannot receive the correct instructions to heat your home.
Your boiler has detected a problem with a temperature sensor that controls the heat of your water, which might cause your heating or hot water to stop working correctly.
Your boiler is having trouble managing the temperature of its internal water circuits, which will likely stop your heating and hot water from working correctly.
Your boiler's computer is confused because it thinks internal temperature sensors are plugged into the wrong place, preventing the unit from operating safely.
Your boiler has stopped working because its internal control board has detected that some wiring or sensors have been plugged into the wrong ports during a service or repair.
Your boiler has detected an electrical fault with one of its internal temperature sensors, which is preventing it from monitoring heat levels safely and will likely stop it from working.
Your boiler has detected a broken wire or a faulty connection to one of the internal temperature sensors, which is preventing it from heating properly.
Your boiler has detected an electrical fault with its main temperature sensor, causing the system to shut down safely to prevent overheating.
Your boiler has lost connection with a temperature sensor, which means it cannot accurately monitor the water temperature to operate safely.
Your boiler has detected an electrical problem with the sensor that measures the temperature at the bottom of your solar hot water cylinder.
Your boiler's hot water system has lost communication with the temperature sensor in your solar cylinder, meaning it cannot accurately monitor the water temperature.
Your boiler has stopped providing hot water correctly because a temperature sensor connected to your solar heating system has developed an electrical fault.
Your boiler is struggling to read the temperature of the water in your solar cylinder due to a broken or faulty sensor or connection.
Your solar heating system has stopped circulating fluid properly, likely due to a blockage or trapped air bubbles within the pipes.
Your solar heating system is unable to move water because the pump is stuck or there is an air bubble trapped inside the pipes.
Your solar heating pump has stopped moving because something is physically blocking it from spinning internally.
Your solar heating system has stopped working properly because either air is trapped in the pipes or the circulation pump has become stuck.
Your solar heating system is unable to move water because the pump is stuck or there is an air pocket trapped in the pipes.
Your boiler has detected that the wrong type of temperature sensor has been plugged into the system control board.
Your boiler has detected that an incorrect or incompatible temperature sensor has been installed, meaning it cannot properly monitor the system's heat levels.
Your boiler has detected that the wrong type of sensor has been installed or connected for your hot water system, causing a communication error within the internal electronics.
Your boiler has detected that an incorrect or incompatible internal sensor has been fitted, preventing it from reading temperatures accurately.
Your boiler has detected that the wrong type of temperature sensor has been installed or configured for your hot water cylinder.
Your boiler has detected that the wrong type of temperature sensor has been installed or configured for your hot water system.
Your boiler's control system has detected that the wrong type of temperature sensor has been installed or configured for your hot water system.
Your boiler has lost communication with the temperature sensor that monitors your hot water cylinder, meaning it cannot accurately heat your water.
Your boiler's internal sensor has detected a communication issue with your solar heating system, meaning the solar panels aren't currently helping to heat your water.
Your boiler has detected that its internal temperature sensors are reading heat in the wrong order, causing the system to shut down for safety.
Your boiler has become confused because its internal temperature sensors appear to have been plugged into the wrong ports or are reading backwards.
Your boiler has detected that a temperature sensor is installed in the wrong place, meaning the system cannot accurately monitor the heat coming from your solar panels or heating circuit.
Your boiler's solar heating sensor has detected an issue, likely meaning your solar panels aren't assisting with your hot water production as they should.
Your boiler has detected that a temperature sensor is sending an unusual reading, suggesting it may have been knocked out of place or is reporting a sudden, impossible heat spike.
Your boiler's automatic routine to heat your solar hot water tank to a safe, bacteria-killing temperature has failed to complete.
Your boiler is warning you that your solar-heated water tank hasn't reached a high enough temperature to safely kill off any potential bacteria.
Your solar hot water system hasn't reached the high temperature needed to kill bacteria, usually because the solar pump is struggling or the settings are incorrect.
Your boiler is displaying an advisory message stating that its built-in solar heating controls have not been set up or activated.
Your boiler is trying to communicate with solar heating equipment that hasn't been set up yet or has had its settings lost.
Your boiler's internal pump settings have been switched to a manual override mode, preventing it from operating automatically as it should.
Your boiler's internal pump has been left in a manual testing mode, meaning it isn't responding correctly to your heating demands.
Your boiler's internal pump has been manually overridden or is stuck in a manual operation mode, which is preventing it from working automatically to heat your home.
Your solar heating system is moving water too quickly or too slowly, which means it cannot heat your water efficiently.
Your boiler has detected an issue with the speed at which liquid is moving through your solar heating panels, meaning the solar water heating system is not working efficiently.
Your solar heating system is moving fluid too quickly through the roof collectors, which may indicate a settings error or a faulty sensor.
Your solar heating system isn't circulating fluid properly, which means the sun's energy isn't being transferred to your water tank as it should.
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.
Your boiler has detected a critical internal error that has forced it to shut down to prevent damage, meaning you currently have no heating or hot water.
Your boiler has detected a critical internal error across multiple systems, which has forced the unit to shut down to prevent damage.
Your boiler has detected a critical internal error that prevents it from operating safely or correctly.
Your boiler is having trouble accurately measuring the temperature of your hot water, so it may struggle to keep the water at a consistent heat while you are using it.
Your boiler is simply reminding you that it is time for its annual safety service as programmed by your installer.
Your boiler is stuck in a low-power service mode, meaning it will provide heat but won't reach full power or respond to normal temperature demands.
Your boiler is stuck in a service mode where it runs at maximum power constantly, which is usually triggered during maintenance or testing.
Your boiler is currently running a self-cleaning routine to remove trapped air bubbles from the internal pipes and pump.
Your boiler is currently running a routine internal cleaning cycle to fill up its condensation trap and is not actually broken.
Your boiler is working normally, but it is displaying a reminder that its annual service is now due because the programmed operating hours have been reached.
Your boiler is simply displaying a reminder that its annual service is due soon or is now overdue.
Your boiler is currently trying to light its internal pilot flame and will continue making a clicking sound for up to 30 seconds to get the process started.
Your boiler is currently running an internal self-test on its air extraction fan to ensure it is working correctly, which is a normal automated process.
Your boiler is currently performing a routine check to ensure the water pump is working correctly before it starts heating your home.
Your boiler is currently running a background self-test to ensure the internal component that switches between heating your radiators and heating your hot water is working correctly.
Your boiler is performing a routine internal safety check on the component that detects the flame, but it has identified a fault in its ability to monitor this safely.
BoilerFaultCodes