164 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Turbomax
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Your boiler's internal components are failing to talk to each other, meaning the system cannot start up to provide heat or hot water.
Your boiler's external pump, which helps push heat around your home, has stopped working correctly.
Your boiler is currently restricted to a lower power setting for heating, meaning your radiators might take much longer than usual to get warm.
Your boiler is simply cooling itself down after providing heat, which is a normal part of its operation rather than a breakdown.
Your boiler is temporarily resting because it has reached its target temperature and is waiting for the water to cool down slightly before firing up again to save energy.
Your boiler's internal computer is currently displaying the live temperature of your hot water rather than showing a specific fault code.
Your boiler is currently showing the live temperature reading of the 'warm start' sensor, which keeps a small amount of water pre-heated for faster hot water delivery.
Your boiler is currently waiting for the water temperature to drop or is processing a specific demand for heat, which is a normal operational status rather than a breakdown.
Your boiler is displaying the current temperature setting for the 'warm start' feature, which keeps a small amount of water pre-heated so you get hot water at your taps more quickly.
Your boiler is receiving a signal from your external thermostat or timer telling it to provide heating or hot water, and it is behaving as it should.
Your boiler is receiving a instruction from an external thermostat or home automation system telling it what temperature to run at.
Your boiler is unable to circulate water around the system because its internal pump has stopped working or is jammed.
Your boiler is having trouble communicating with the pump that fills your hot water cylinder, which may result in a lack of hot water.
Your boiler is having trouble circulating hot water through the system, which typically means the internal pump is stuck or has failed.
Your boiler is struggling to set the correct speed for the internal pump that moves water through the system.
Your boiler's internal pump is running at an incorrect speed, which prevents the system from moving heat to your taps or radiators effectively.
Your boiler has sensed that the water returning from your radiators is hotter than it should be, causing the system to temporarily throttle back its power.
Your boiler is currently set to run the internal pump continuously, often due to a specific setting or a need to prevent the pipes from freezing.
Your boiler is having trouble managing the speed of its internal pump, which may lead to inefficient heating or your system struggling to circulate water properly.
Your boiler is currently ignoring the temperature dial because it has reached the maximum pre-set safety limit for your hot water storage.
Your boiler is signalling that it is currently busy preparing or providing hot water through your taps.
Your boiler is currently set to summer mode, which means your hot water is working but your central heating has been deactivated.
Your boiler's internal water pressure is dropping too low while the pump is running, which usually points to a leak or a lack of water in the system.
Your boiler is currently providing hot water because it has received a digital request from your external heating controls or smart thermostat.
Your boiler is having trouble communicating with an internal component or external accessory, which may prevent your heating or hot water from turning on correctly.
Your boiler is having trouble communicating with an internal switch that controls an external accessory or heating component.
Your boiler is experiencing a communication fault with internal electrical switching components, usually meaning an accessory part is not responding correctly.
Your boiler is struggling to open the gas supply because of a communication issue between the electronics and the internal gas valves.
Your boiler has identified a problem with the fan that clears away waste gases, causing the system to shut down for safety.
Your boiler has detected that the internal fan is spinning at the wrong speed, preventing the system from clearing waste gases and starting up safely.
Your boiler is struggling to supply enough gas to the burner, likely because it is too cold outside or there is a problem with the gas pipework.
Your boiler is struggling to detect when you turn on your hot taps, meaning you may experience cold water or intermittent temperature changes.
Your boiler is displaying its current target heating temperature rather than a fault code, meaning it is operating as designed.
Your boiler is currently showing you a live reading of the water temperature returning from your radiators rather than indicating a fault.
Your boiler is struggling to detect the flame needed to heat your water or radiators, causing it to shut down for safety.
Your boiler's outdoor sensor is struggling to communicate the outside temperature, which means your heating might not adjust correctly to the weather.
Your boiler's fan is struggling to run at the correct low speed required for efficient operation.
Your boiler's computer is reporting an internal memory error regarding how fast the fan should spin, which prevents it from starting up safely.
Your boiler is notifying you that it is currently using energy from your solar heating system to pre-heat your water.
Your boiler has shut down because it is getting too hot and has triggered its safety limit multiple times to prevent damage.
Your boiler has failed to ignite multiple times and has now locked itself out for safety reasons.
Your boiler is taking longer than usual to light the flame, which could indicate a minor delay in the starting process.
Your boiler is struggling to light its flame after several attempts and has stopped for safety.
Your boiler is taking a short, programmed break to prevent the burner from switching on and off too frequently, which protects the internal parts and saves energy.
Your boiler is struggling to light the flame on its first try, which often means it needs more than one attempt to provide you with heating or hot water.
Your boiler has failed to light the flame twice in a row, meaning it cannot provide heating or hot water until the issue is resolved.
Your boiler is currently stuck in a configuration mode where it is trying to decide whether to send heat to your radiators or your hot water taps.
Your boiler is signalling that the heating temperature dial is set to its maximum limit, which is often an advisory message rather than a complete breakdown.
Your boiler is continuing to run its internal water pump for a set period after heating your hot water to prevent the unit from getting too hot.
Your boiler is notifying you of an adjustment to the pre-heat temperature used for quicker hot water delivery.
Your boiler is taking too long to heat up the internal hot water storage tank, which often means heat isn't transferring properly.
Your boiler is taking a short, programmed break to prevent the burner from switching on and off too frequently, which protects the internal components from unnecessary wear.
Your boiler is limiting the amount of power it uses to heat your hot water, which may lead to it taking longer than usual to reach the desired temperature.
Your boiler is limiting the temperature it uses to heat your hot water, likely because it has detected a measurement error or an overheating risk in the storage cylinder.
Your boiler is simply displaying how many hours it has spent providing central heating; this is an information status rather than a fault.
This is just an informational message showing how many hours your boiler has spent providing hot water and does not indicate a fault with your system.
Your boiler is notifying you that it is currently firing up the burner to begin heating your radiators.
Your boiler is correctly telling you it is preparing to heat up water for your taps rather than for your radiators.
Your boiler is simply reminding you that its annual service is due soon and there is no actual fault with the system.
Your boiler's electronic control panel is currently communicating with an external smart thermostat or digital controller to determine how much heat is needed.
Your boiler's external temperature sensor is communicating its status, but the system is having trouble processing the radio signal correctly.
Your boiler’s computer is confused because it hasn't been programmed with the correct identity code for this specific model.
Your boiler has lost its specific configuration settings and has reverted to its original factory state, meaning it may not communicate correctly with your heating system.
Your boiler has entered a specialist diagnostic mode usually reserved for engineers to perform advanced testing and setup.
Your boiler has detected an internal technical fault that requires an expert to diagnose and reset.
Your boiler has lost communication with its internal temperature sensor, preventing it from knowing how hot the water is and causing it to shut down for safety.
Your boiler has lost connection with the internal thermometer that monitors water temperature, causing the system to shut down for safety.
Your boiler has stopped working because a internal sensor that monitors water temperature has lost its electrical connection.
Your boiler has failed to ignite and cannot produce heating or hot water because it isn't getting a gas supply or the internal spark is failing.
Your boiler has stopped working because it cannot properly measure the temperature of the water returning from your radiators.
Your boiler is failing to start because it cannot light the gas needed to create heat.
Your boiler has shut down because it has reached an unsafe temperature, likely due to water not circulating properly through the system.
Your boiler's internal temperature sensor has stopped working correctly, meaning the system cannot accurately monitor the heat of the water leaving the unit.
Your boiler has detected an electrical connection issue with the sensor that monitors the water temperature returning to the unit.
Your boiler has detected that water is failing to circulate through the system, causing the unit to stop working to avoid overheating.
Your boiler has detected a internal blockage that is preventing water from flowing correctly and affecting the system's pressure.
Your boiler has detected an electrical short circuit in its internal wiring, likely related to the temperature sensor system.
Your boiler has detected an electrical wiring issue, or the power supply is not configured correctly, preventing it from starting safely.
Your boiler has reached an unsafe temperature and has automatically shut down to prevent damage.
Your boiler has stopped working because the internal burner cannot stay lit or failed to ignite correctly.
Your boiler has detected that there is not enough water pressure in the system to operate safely, causing it to shut down to prevent overheating.
Your boiler has shut down because the water inside is heating up too quickly or unevenly, likely due to a circulation blockage or a pump issue.
Your boiler is not circulating enough water through the system, causing it to overheat and shut down for safety.
Your boiler has shut down because the internal exhaust gases are getting too hot, which is a safety feature to prevent damage or dangerous fumes.
Your boiler has stopped working because it cannot properly control the flow of gas needed to stay alight.
Your boiler has detected a flame when there shouldn't be one, which has caused it to shut down for safety purposes.
Your boiler is failing to light the gas flame and has locked itself out for safety.
Your boiler was working but the flame has gone out unexpectedly, meaning the system cannot heat your home or water.
Your boiler has detected an issue with the fan that safely pushes waste gases out of your home, causing the system to shut down for safety.
Your boiler's internal communication system has failed, meaning the control panel cannot talk to the parts that heat your water.
Your boiler has detected an internal electrical problem with the gas control system and has shut down as a safety precaution.
Your boiler is failing to communicate correctly with the gas valve, meaning it cannot safely manage the fuel needed to provide heating and hot water.
Your boiler has detected a safety issue where the gas valve is not closing properly, meaning gas could still be flowing when it shouldn't be.
Your boiler's internal computer brain has suffered a memory failure and can no longer process the instructions needed to operate.
Your boiler's internal computer has detected a conflict between its sensors or an electrical fault, causing the system to shut down for safety.
Your boiler’s internal control board has become too hot and has shut down as a safety precaution to prevent damage.
Your boiler has detected an internal electrical problem with the system that manages the burner flame, meaning the device cannot safely stay lit.
Your boiler is struggling to keep a steady flame alight because the gas supply is inconsistent or contains air pockets.
Your boiler’s control board and display screen are no longer communicating correctly because they haven't been programmed to recognize each other.
Your boiler's temperature sensor has stuck on a single reading, so the system has shut down because it cannot safely monitor how hot the water is getting.
Your boiler has detected an unusual temperature difference between the water leaving the unit and the water returning to it, often caused by a faulty sensor or a circulation blockage.
Your boiler's internal sensor can no longer accurately read the water pressure, causing the system to shut down for safety.
Your boiler's internal sensor is struggling to accurately measure the water pressure, which prevents the system from operating safely.
Your boiler is failing to detect that the pump is moving water, which means it cannot safely heat up and has shut down to protect itself.
Your boiler has switched itself off because a safety sensor detected that the main heating component has reached an dangerously high temperature.
Your boiler has detected a problem with the pump that removes waste water or an issue with the flap that controls exhaust gases.
Your boiler is struggling to provide hot water correctly because a sensor that monitors water temperature has lost its connection or stopped working.
Your boiler has detected that the temperature sensors aren't tracking heat changes correctly, often because there isn't enough water moving through the system to be measured.
Your boiler has detected that its temperature sensors are giving unusual or conflicting readings, which prevents it from heating up safely.
Your boiler has detected that the temperature sensors on the main pipes are either loose, incorrectly installed, or not reading the water flow correctly.
Your boiler is currently running a self-cleaning sequence to remove air bubbles from the pipes and internal components.
Your boiler has become stuck in a manual testing mode used by engineers and is likely failing to exit this program correctly.
Your boiler is currently running a manual test mode to check its performance at the lowest power setting.
Your boiler is currently running a self-diagnostic test to help fill and vent air from the system and is not indicating a hardware failure.
Your boiler is working correctly but currently waiting for a command from your thermostat to turn the heating on.
Your boiler is unable to start the heating process because its internal fan, which safely clears waste gases, is failing to spin up properly.
Your boiler is currently preparing to start the heating cycle and is warming up the fan.
Your boiler has stopped heating up because the water is not being pumped through the system properly.
Your boiler is currently preparing to provide heating by running the internal pump to move water through the system.
Your boiler is struggling to start the burner to provide heating, which means your radiators will not warm up.
Your boiler is failing to light the gas burner after several attempts, meaning your heating and hot water will not work.
Your boiler is currently firing up to provide central heating, but it has detected a problem with the burner operation.
Your boiler is operating normally and is currently firing up to provide central heating.
Your boiler is failing to settle down correctly after heating your home because the internal fan is running for longer than the system expects.
Your boiler is struggling to clear fumes from the system because the internal fan is running longer than expected during its cooling-down phase.
Your boiler is temporarily finishing its heating cycle by running the pump to cool down, but it has detected that this process isn't working quite as expected.
Your boiler is staying on longer than usual after central heating use because it is struggling to circulate water and cool itself down properly.
Your boiler is temporarily in a waiting period to prevent it from cycling on and off too frequently after reaching its target temperature.
Your boiler is temporarily resting because it has reached its target temperature and is waiting for a short period before restarting to prevent unnecessary wear.
Your boiler has detected that you have turned on a hot water tap and is currently working to provide hot water to your home.
Your boiler is trying to provide hot water, but the internal fan is failing to start up properly to clear the system.
Your boiler has detected a request for hot water but the air flow sensor is not responding correctly, preventing the system from firing up.
Your boiler is briefly keeping the pump and fan running to cool itself down after you have finished using the hot water.
Your boiler is failing to switch off the fan after providing hot water, which is preventing it from starting the next heating cycle.
Your boiler is struggling to circulate water after you have used the hot water tap, which is often caused by a blockage or a valve that is stuck.
Your boiler has detected that you have turned on a hot water tap and is currently preparing to heat the water for you.
Your boiler is trying to provide hot water but cannot safely start the fan required to clear exhaust fumes.
Your boiler has detected that hot water isn't moving through the system correctly, which is preventing it from heating up your taps.
Your boiler is failing to light the burner when you turn on your hot water tap.
Your boiler is currently working as it should by firing up the burner to heat your hot water.
Your boiler is staying in its cooling-down phase for too long after you have finished using hot water.
Your boiler is briefly keeping its internal fan running after you have used the hot water to help the system cool down properly.
Your boiler is briefly running the internal pump after you have finished using hot water to safely cool down the heat exchanger.
Your boiler is taking a short, programmed break to prevent the burner from turning on and off too frequently while heating your water.
Your wall thermostat has told the boiler to stay off, likely because the room is already warm enough or the thermostat timer is set to an 'off' period.
Your boiler is currently set to summer mode, which means it is providing hot water but has intentionally turned off the central heating functions.
Your boiler has temporarily stopped because the fan, which clears exhaust gases, isn't spinning at the correct speed.
Your boiler has paused operation because it believes the internal temperature has dropped low enough to risk freezing the pipework.
Your boiler has received a signal from your thermostat or internal settings saying that heat is not currently required, so it is staying in standby mode.
Your boiler has paused its heating process because an external safety switch, usually linked to your condensate pump or an overheat sensor, has tripped.
Your boiler is currently running at a lower power level because it has detected a minor internal issue and is protecting itself from damage while still trying to provide some heat.
Your boiler has too much water inside it, causing the internal pressure to rise to an unsafe level.
Your boiler has paused because a safety flap in the flue system is stuck or sending an incorrect signal, preventing the exhaust gases from leaving safely.
Your boiler is struggling to keep its pilot flame alight when running at its lowest setting, meaning it may stop working when it tries to save energy.
Your boiler has temporarily stopped working because it cannot move water around the system fast enough, likely due to a blockage or a pump issue.
Your boiler has temporarily paused operation because it has detected a lack of water circulation or a rapid rise in temperature that could lead to overheating.
Your boiler has temporarily paused operation to prevent overheating and should restart automatically once the internal sensor detects a safe temperature.
Your boiler is temporarily limiting its power because the burner's flame is being disturbed by external wind or internal air flow issues.
Your boiler has failed an automatic check to identify the type of gas being supplied, which has caused it to stop running for safety reasons.
Your boiler is struggling to move enough water through the system, which is causing it to work harder than it should.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, causing it to stop running for safety.
Your boiler is temporarily pausing because it has noticed an unusual difference in temperature readings and needs to double-check its internal sensors before starting up again.
Your boiler is currently idle because it has not received a signal from your thermostat or timer to turn the heating on.
Your boiler is failing to light the flame when you turn on your hot water taps.
BoilerFaultCodes