102 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start but cannot get the flame to stay lit, so it has safely shut itself down to avoid wasting fuel.
Your boiler has detected that water is not flowing through the system correctly, so it has shut down to protect itself from overheating.
Your boiler has automatically turned itself off because the water inside it has become dangerously hot.
Your boiler has detected an internal error during its startup safety check and has stopped working to prevent any potential risks.
Your boiler has stopped working because it tried to light three times but could not detect a flame.
Your boiler has stopped working because the water pressure is too low, meaning there isn't enough water inside the system to operate safely.
Your boiler has shut down because it has detected that the water inside has become dangerously hot and is potentially overheating.
Your boiler has tried to light several times during its cycle but the flame keeps going out, causing the system to lock itself for safety.
Your boiler has detected that water isn't moving through the system properly, which has caused it to stop working to avoid overheating.
Your boiler has detected that water is not moving around the system properly, which has caused it to shut down to prevent overheating.
Your boiler is continuing to detect a flame even after it should have turned off, which is a safety concern that requires a professional inspection.
Your boiler thinks it sees a flame even though it hasn't turned the gas on yet, which is confusing the safety system.
Your boiler has detected that water is not circulating correctly through the system, preventing it from firing up to provide heat or hot water.
Your boiler has detected that a internal water sensor is stuck in the 'on' position, preventing the system from starting its safety checks correctly.
Your boiler has detected a fault with the fan and has shut down as a safety precaution to ensure exhaust gases are properly removed.
Your boiler's internal computer has encountered a temporary communication glitch or a technical hardware failure that is preventing it from running safely.
Your boiler’s internal computer has encountered a communication error and is struggling to manage its operations correctly.
Your boiler’s internal computer has encountered a communication error or software glitch that is preventing it from monitoring the system safely.
Your boiler has tried to light several times but has failed to create or detect a flame, causing the system to lock out for safety.
Your boiler is trying to fire up but cannot detect the water getting warmer, so it has shut down as a safety precaution.
Your boiler has detected that the water inside is getting much too hot and has shut down as a safety precaution.
Your boiler is struggling to keep a steady flame going and has shut down after several failed attempts to stay lit.
Your boiler is still detecting a flame even after it has tried to shut the gas off, which is a significant safety concern.
Your boiler has sensed a flame when there shouldn't be one, which usually means a sensor is confused or the gas system isn't closing correctly.
Your boiler has detected that water isn't flowing correctly through the system, so it has shut down to prevent overheating.
Your boiler has detected that a internal water sensor is stuck in the 'on' position even when the pump isn't running, preventing the system from starting safely.
Your boiler has stopped working because the fan that helps remove waste gases is not spinning or communicating correctly with the system.
Your boiler's computer system is having trouble talking to its internal sensors, which means it cannot monitor the system safely.
Your boiler has detected that the water inside the system is getting dangerously cold and has automatically fired up to prevent the pipes from freezing.
Your boiler is currently heating the water stored in your external cylinder, which is a normal operating status rather than a fault.
Your boiler has stopped working because it failed to light or stay lit, meaning it cannot provide heating or hot water safely.
Your boiler has detected a failure in its internal safety systems and has shut itself down to prevent damage, meaning you currently have no heating or hot water.
Your boiler is operating normally and is currently heating your home.
Your boiler is simply showing you the room temperature you have selected while you are turning the control knob.
This is a normal operational message indicating that the boiler is currently heating water for your taps or shower.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that a temperature sensor responsible for your heating water is disconnected or faulty, which is preventing the system from warming up properly.
Your boiler has detected a fault with the sensor that monitors the temperature of the water leaving the unit to heat your radiators.
Your boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and can no longer monitor the water coming back from your radiators.
Your boiler has shut down because a safety sensor has detected that your underfloor heating system is getting too hot.
Your boiler's internal computer has encountered a communication error or software glitch, preventing it from managing the heating process safely.
Your boiler is struggling to accurately measure the water temperature leaving and returning to the unit, which has caused it to stop working for safety.
Your boiler has detected a safety issue with the flame and has shut down to prevent damage or unsafe operation.
Your boiler has stopped working because it cannot safely confirm that the waste gases are being blown out of the flue.
Your boiler is failing to light properly, which means the system cannot create the flame needed to heat your home or water.
Your boiler has detected that it is dangerously overheating even though it is not currently supposed to be running.
Your boiler has detected an issue with how it is venting waste gases, which prevents it from firing up for your safety.
Your boiler is struggling to provide hot water because the internal sensor that measures water temperature is broken or disconnected.
Your boiler's temperature sensor for hot water has developed an electrical fault, meaning the system cannot safely tell how hot your water is and has stopped working as a precaution.
Your boiler has detected that a temperature sensor for your underfloor heating is broken or disconnected, which may prevent your floors from warming up properly.
Your boiler thinks a flame is burning even though it hasn't turned the gas on, causing it to shut down for safety.
Your boiler has detected that the electrical wiring supplying it is connected backwards, which is a safety issue that prevents it from starting.
Your boiler is struggling with the electrical power coming into your home, which is preventing it from starting up properly.
Your boiler has detected an electrical fault with the sensor that confirms the flame is burning, causing the system to shut down for safety.
Your boiler has lost connection with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot safely regulate your heating.
Your boiler has lost communication with the sensor that tracks the temperature of the water returning from your radiators, often resulting in the system shutting down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit to heat your home.
Your boiler has detected a fault with a sensor that monitors the temperature of the water returning from your radiators, meaning it cannot operate safely.
Your boiler has tried to start five times without success and has now locked itself out for safety.
Your boiler has detected an unusually high temperature reading even though it should be resting, which usually suggests a faulty sensor or a circulation problem.
Your boiler is unable to read the temperature of the water coming out of your taps, which means it cannot heat your hot water correctly.
Your boiler is struggling to provide hot water because the internal sensor that monitors the water temperature has failed.
Your boiler has lost communication with the temperature sensor that monitors your underfloor heating, meaning it cannot safely regulate the floor's warmth.
Your boiler thinks it sees a flame even though the gas should be turned off, which is a safety conflict that prevents the system from starting.
Your boiler has detected that the electrical wiring has been connected incorrectly, which is preventing it from running safely.
Your boiler is struggling to operate because the electrical power coming from your mains supply is unstable or incorrect.
Your boiler has detected an electrical fault with the sensor that confirms the burner is lit, meaning it cannot safely start up to provide heat or hot water.
Your boiler has stopped working because it can no longer accurately measure the temperature of the water leaving the unit to heat your home.
Your boiler has lost its connection to the sensor that monitors water returning from your radiators, meaning it cannot safely regulate the heating temperature.
Your boiler has detected a fault with the sensor that monitors the temperature of the water leaving the boiler, preventing it from heating your home safely.
Your boiler has stopped working because one of its internal sensors is reporting an electrical fault and can no longer monitor the temperature of the water coming back from your radiators.
Your boiler's computer brain has encountered a general software or electronic communication error and cannot function.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water.
Your boiler has detected that there is not enough water pressure flowing through the system to heat your home safely.
Your boiler has detected that it is running much too hot and has automatically shut itself down to prevent any damage or safety issues.
Your boiler has stopped working because it cannot detect enough water pressure circulating inside the system.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler is currently displaying a setting value rather than an error, indicating the maximum heating power percentage is being adjusted or viewed.
Your boiler is experiencing a planned pause in its heating cycle to prevent it from switching on and off too frequently.
Your boiler is currently adjusting the strength of its ignition flame to find the best way to light based on recent performance.
Your boiler has detected that the water pump is not running correctly, so it has safely shut itself down to prevent damage to the system.
Your boiler has stopped working because it failed to ignite the gas flame to heat your home or water.
Your boiler has detected that water is not moving through it correctly, which has caused it to turn itself off to prevent overheating.
Your boiler has switched itself off because it has become dangerously hot and needs to cool down to prevent internal damage.
Your boiler tried to light the burner but couldn't detect a flame, so it is currently not providing heating or hot water.
Your boiler is struggling to light its flame, meaning it cannot provide heating or hot water until the issue is resolved.
Your boiler is struggling to provide hot water because it cannot correctly read the temperature of the water used for your taps.
Your boiler has detected a fault with the sensor that monitors hot water temperature, meaning you will likely experience cold or inconsistent water from your taps.
Your boiler's flame is lifting away from the burner or is unstable, causing the system to shut down for safety.
Your boiler has lost connection with the sensor that monitors the temperature of your hot water tank, meaning it cannot heat your water correctly.
Your boiler's hot water tank sensor has developed an electrical fault, meaning it can no longer accurately monitor the water temperature.
Your boiler has detected that the water within your internal storage tank has become too hot and has stopped operating for safety.
Your boiler has lost connection to the sensor that monitors the temperature outside, which may cause your heating to respond incorrectly to the weather.
Your boiler has lost its connection to the outside temperature sensor, which means the heating might not adjust correctly to the weather until it is fixed.
Your wall-mounted remote control unit has lost its connection to the boiler, meaning the system cannot accurately monitor your home's temperature.
Your boiler's internal computer brain has detected a safety error while trying to ignite, causing the system to lock itself down to prevent damage.
Your boiler has detected that the water temperature leaving the unit is incorrect, which is likely preventing your heating from operating correctly.
Your boiler has detected that the water returning from your radiators is at an unusual temperature, which usually means the water isn't flowing through the system correctly.
Your boiler is displaying the current temperature of the hot water leaving the unit, which is usually an informative status update rather than a critical system failure.
Your boiler is having trouble detecting the flame needed to heat your water, which is causing it to shut down for safety.
Your boiler has detected that water isn't moving through the system properly, so it has shut down to prevent itself from overheating.
BoilerFaultCodes