111 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has tried to light several times but failed, so it has locked itself for safety.
Your boiler has switched itself off because it has detected that the water inside has become too hot.
Your boiler has stopped working to prevent a technical fault from causing damage, essentially 'tripping' itself off like a fuse.
Your boiler has stopped working because the water pressure is either too low, too high, or the water isn't moving through the system correctly.
Your boiler has detected an issue with the ventilation fan, which means it cannot safely clear exhaust fumes and will not ignite.
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 is struggling to accurately measure the temperature of your hot water due to a faulty internal sensor.
Your boiler's outside temperature sensor has failed, meaning the system doesn't know how hard it needs to work to heat your home based on the weather.
Your boiler has shut down because it has detected an unsafe build-up of heat or exhaust gases in the flue system.
Your boiler has shut down because it detected that the exhaust gases have become dangerously hot, potentially damaging internal safety components.
Your boiler is detecting a flame when it shouldn't be there, which is a safety mechanism that prevents the system from starting up.
Your boiler has detected a problem with the sensor that monitors the temperature of the water coming back from your radiators, preventing it from heating your home safely.
Your boiler has detected a fault with a temperature sensor that monitors the water returning to the unit, causing the system to stop working for safety.
Your boiler has detected that the water is heating up too quickly or not circulating properly, causing the system to shut down to prevent overheating.
Your boiler is overheating because the water is getting too hot too quickly, usually due to a lack of proper water flow through the system.
Your boiler has likely overheated because water is not circulating properly through the system.
Your boiler has overheated or the water is not circulating properly through the system, causing it to shut down for safety.
Your boiler is struggling to move water through the system correctly, which is causing it to shut down to prevent overheating.
Your boiler has likely stopped working because water is not moving through the system quickly enough to prevent it from overheating.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution.
Your boiler has shut down because the internal exhaust gases have reached a temperature that is dangerously high.
Your boiler has detected that the water isn't heating up or circulating correctly immediately after starting, causing it to shut down for safety.
Your boiler has stopped working because it cannot detect the water temperature rising quickly enough after firing up.
Your boiler has detected a problem with one of its internal monitoring sensors, which is preventing the system from operating correctly.
Your boiler's internal monitoring system has detected a fault with one of its temperature sensors, which is preventing the unit from operating correctly.
Your boiler has detected an internal electronic failure and has shut down for safety because it cannot correctly control the gas valve.
Your boiler has detected an internal electrical fault with the gas valve control system and has shut down for safety.
Your boiler has stopped working because its internal safety computer cannot correctly control the gas valve, meaning the boiler has locked itself out for safety.
Your boiler's main control board has detected a failure in the internal switch that controls the gas valve, preventing the system from firing up for safety.
Your boiler has detected a flame that continues to burn even after the gas valve should have closed, which is a safety fault that requires a professional inspection.
Your boiler is unable to control the flame size properly because a key electronic connection to the gas control system has failed.
Your boiler is unable to control its heat levels properly because a key internal communication cable has come loose or failed.
Your boiler has sensed a blockage or issue with the flue pipe that safely carries exhaust fumes out of your home, causing it to shut down for safety.
Your boiler has detected that waste gases cannot properly escape through the flue pipe, causing the system to shut down for safety.
Your boiler is failing to keep the flame lit and has locked itself out after several unsuccessful attempts to stay running.
Your boiler is repeatedly failing to keep a steady flame, causing it to shut down for safety.
Your boiler has detected that its internal temperature sensors are giving very different readings, causing the system to shut down for safety.
Your boiler has detected that its temperature sensors disagree with each other, so it has shut down as a safety precaution.
Your boiler has detected an issue with the electrical power timing reaching the unit, which is preventing it from running safely.
Your boiler is struggling to operate because the electrical power entering the unit does not match the required frequency standards.
Buttons on the control panel appear to be stuck or are not communicating correctly with the boiler's internal computer.
Your boiler’s control panel buttons are stuck or faulty, preventing you from changing settings or resetting the unit.
Your boiler has stopped working because the water pressure is too low or it is struggling to light the burner.
Your boiler is having trouble talking to its smart thermostat or external controller, meaning it may not receive instructions to turn the heating on.
Your boiler is having trouble 'talking' to your smart thermostat or external controls, meaning it cannot receive instructions to provide heating or hot water.
Your boiler needs to perform an automatic self-calibration of its gas valve and combustion settings to ensure it operates efficiently.
Your boiler is requesting a system recalibration to ensure the gas and air are burning correctly and efficiently.
Your boiler is struggling to maintain a stable flame because the internal controls are detecting that the gas is not burning correctly.
Your boiler is struggling to manage the flame correctly and has shut down as a safety precaution because it cannot maintain a stable burn.
Your boiler is struggling to get enough gas to stay lit, which has caused it to stop working as a safety precaution.
Your boiler is struggling to get enough gas to stay lit, which means it cannot heat your home or water safely.
Your boiler's internal computer has lost its settings and cannot correctly control the power of the burner.
Your boiler is struggling to get enough gas to stay lit, which has caused it to stop working for safety reasons.
Your boiler is struggling to receive enough gas to operate correctly and has shut down as a safety precaution.
Your boiler's electronic brain is struggling to properly manage the heat output, which usually means it cannot control the gas flow correctly.
Your boiler's electronic brain is having trouble communicating with the internal gas control valve, preventing the system from regulating the flame height correctly.
Your boiler's internal computer has encountered a technical glitch or an issue with the electrical power coming into your home.
Your boiler has detected an internal computer error or an unstable electrical supply, which is preventing it from running safely.
Your boiler has stopped working because it has been reset too many times in a short period and has now locked itself for safety.
Your boiler has been reset too many times in a short period and has now permanently locked itself for safety.
Your boiler has detected an issue with the electrical power supply coming into your home, meaning the electrical timing does not match what the boiler requires to run safely.
Your boiler has shut down completely because it has experienced several technical faults in a short period and has locked itself for safety.
Your boiler is not receiving the correct amount of electrical power to operate safely and has shut down as a precaution.
Your boiler has stopped working because it cannot light the burner or detect that a flame has started.
Your boiler has switched itself off because it has detected that the internal water temperature has become too hot.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler has detected that the electrical wiring in your home or the plug is connected the wrong way round, preventing it from starting safely.
Your boiler is failing to light the gas flame despite several attempts, meaning it cannot provide heat or hot water.
Your boiler has stopped working because the fan that clears away waste gases is not spinning at the correct speed.
Your boiler has shut down because it cannot safely expel waste gases, likely due to a blockage in the flue pipe or a fault with the internal fan.
Your boiler has stopped working because it cannot safely push exhaust gases out of the flue pipe.
Your boiler’s internal computer brain has developed a communication fault or hardware failure and can no longer control the heating system.
Your boiler thinks it sees a flame even though the gas should be turned off, which is a safety conflict causing the system to shut down.
Your boiler’s internal computer has developed a serious fault and can no longer control the heating or hot water system.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler has detected that the exhaust gases are getting too hot, causing it to shut down for safety.
Your boiler's internal thermometer that measures the temperature of the water flowing to your radiators has developed a fault and can no longer read the temperature correctly.
Your boiler has shut down because a sensor has detected that the water leaving the unit to heat your radiators is getting too hot.
Your boiler has stopped working because the sensor that monitors the temperature of the water returning from your radiators has developed a fault.
Your boiler has detected that the water returning from your radiators is getting too hot, which often points to a circulation problem or a faulty sensor.
Your boiler's hot water sensor has failed or has a wiring fault, meaning the system cannot accurately measure the temperature of the water coming out of your taps.
Your boiler has stopped working because it cannot detect a steady gas supply or there is a communication error with its internal control board.
Your boiler's computer brain has encountered an internal software or hardware error and can no longer process instructions.
Your boiler’s internal computer has lost its settings and doesn't know how to operate properly, often occurring after a power cut or a part replacement.
Your boiler's main control center has suffered a communication failure or internal fault, preventing the appliance from operating.
Your boiler has switched itself off because the internal temperature sensors are giving conflicting readings and can no longer guarantee safe operation.
Your boiler's internal computer has developed a serious fault and can no longer control the heating or hot water functions.
Your boiler’s internal computer has developed a serious fault and can no longer control the heating and hot water components properly.
Your boiler is having trouble communicating with your thermostat or remote controller, meaning it can't receive the signal to turn the heating on.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has shut down because a safety component detected it was getting dangerously hot, and this fuse now needs to be replaced.
Your boiler has detected a communication problem or a physical fault with the temperature sensor that monitors the main heating water circuit.
Your boiler has lost connection with its outdoor thermometer, meaning it might struggle to adjust its temperature correctly for the weather.
Your boiler has detected that the temperature in the exhaust flue is incorrect or the sensor monitoring it has developed a fault.
Your boiler's main internal computer has developed a fault and can no longer control the heating or hot water functions.
Your boiler's internal computer has developed a serious fault and can no longer control the heating system safely.
Your boiler’s main internal computer has developed a fault and can no longer control the heating or hot water functions.
Your boiler's main internal computer has developed a serious fault and is no longer able to control the heating and hot water systems.
Your boiler's internal computer has developed a critical error, meaning it can no longer control the heating or hot water functions.
Your boiler's main internal computer has developed a serious fault, preventing the system from running safely.
Your boiler's computer controller has suffered an internal failure and can no longer manage the system's operations.
Your boiler's main internal computer has encountered a setup error or a hardware failure and needs a reset or professional attention.
Your boiler has lost its correct configuration settings and needs to be reprogrammed to work safely.
Your boiler’s main internal computer has encountered a major electrical error and can no longer control the heating or hot water operations.
Your boiler has detected a blockage in the waste pipe that carries away excess liquid, causing the system to shut down to prevent leaks.
Your boiler is struggling to confirm that the gas has ignited properly, causing it to shut down as a safety precaution.
Your boiler is unable to light the gas burner because it isn't receiving any fuel, likely due to a mechanical failure or an electrical communication issue with the gas control valve.
Your boiler is struggling to light the burner, meaning it cannot heat your water or radiators.
Your boiler is not receiving enough gas to light the flame or keep it running safely.
Your boiler has detected that the water pressure sensor is not communicating correctly or the main control board is unable to read the system pressure.
Your boiler has switched itself off to prevent damage because the water inside it has become too hot.
BoilerFaultCodes