49 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: HE series
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Your boiler has failed to light, which means you currently have no heating or hot water because the system cannot create a flame.
Your boiler has stopped heating because internal sensors have detected an incorrect temperature reading, often due to a temporary glitch or overheating.
Your boiler is struggling to move water through the system, which is causing it to shut down to prevent overheating.
Your boiler is struggling to accurately monitor how much water is flowing through the system, which is preventing it from heating up correctly.
Your boiler has become too hot and has shut down as a safety precaution to prevent damage.
Your boiler's temperature sensor for hot water has stopped working, meaning the system cannot tell how hot the water is and will likely stop providing it to your taps.
Your boiler has detected that the fan responsible for clearing exhaust gases is not running or communicating correctly, which has caused the system to shut down for safety.
Your boiler has detected that the water inside the heating pipes is getting too hot and has shut down as a safety precaution.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has become too hot and has shut down as a safety precaution to prevent internal damage.
Your boiler has too much water in the system, which puts extra stress on the internal components.
Your boiler's internal thermometer for the central heating has stopped working correctly, meaning the system cannot safely monitor its own temperature.
Your boiler's internal computer brain has encountered a glitch and cannot process its operating instructions.
Your boiler has stopped working because the fan that clears out exhaust gases isn't receiving the correct electrical power.
Your boiler has stopped working because the water returning from your radiators is getting too hot, indicating a possible circulation problem.
Your boiler has shut down because the exhaust pipe is getting too hot, which is a safety mechanism to prevent damage or dangerous fumes.
Your boiler has detected a problem with the internal sensor that monitors the safety of the exhaust gases, causing the system to shut down for protection.
Your boiler is having trouble monitoring the temperature of the water coming back from your radiators, which prevents it from heating your home properly.
Your boiler's main internal unit has frozen due to extremely low temperatures, preventing it from heating your home or water safely.
Your boiler has detected that the water pressure is too low or isn't circulating properly, causing the system to shut down for safety.
Your boiler has detected that the water used for your taps and showers is getting too hot, so it has shut down to prevent damage or scalding.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot.
Your boiler has detected that the exhaust gases are getting too hot or the sensor monitoring them is broken, causing the system to shut down for safety.
Your boiler is having trouble communicating with your smart thermostat or external heating control system.
Your boiler has detected that water is not circulating correctly through the system, causing an unusual temperature gap between the outgoing and incoming pipes.
Your boiler has detected an unusual temperature difference between internal sensors, suggesting a possible circulation issue or a faulty component.
Your boiler has detected an unusual temperature difference between internal sensors, suggesting water isn't flowing correctly or a sensor is failing.
Your boiler has lost its ability to accurately measure water pressure due to a sensor failure, meaning it cannot run safely and has shut itself down.
Your boiler has stopped working because water is not moving around the system properly, which is causing it to overheat and shut down for safety.
Your boiler has detected a problem with the sensor that monitors the flow of water, which means it cannot safely heat your home or water.
Your boiler is struggling to accurately measure the temperature of the water coming out of your taps, which usually means you will have no hot water.
Your boiler has stopped working because the fan that helps remove waste gases is not spinning correctly or cannot communicate with the main control board.
Your boiler has detected that the temperature in the central heating pipes has become too high, causing it to shut down for safety.
Your boiler has detected that the water pressure in the system is too low to run safely and has stopped working to prevent damage.
Your boiler has got too hot and has shut down as a safety precaution to prevent damage.
Your boiler has detected that there is too much water in the system, which puts unnecessary stress on the internal components.
Your boiler's internal computer has encountered a software glitch and is unable to operate correctly.
Your boiler has detected that the water returning from your radiators is getting too hot, causing the system to shut down for safety.
Your boiler has detected that the exhaust gases are getting too hot, so it has shut down as a safety precaution to prevent damage.
Your boiler has detected a fault with the safety sensor that monitors exhaust gases, causing the system to shut down for protection.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators and has stopped working to prevent damage.
Your boiler's internal water system has frozen due to extremely cold temperatures, preventing it from heating up or providing hot water.
Your boiler has detected that the hot water sensor is getting too hot, causing the system to shut down for safety.
Your boiler is having trouble communicating with your external smart thermostat or heating controls, meaning it cannot receive the correct signals to turn on or off.
Your boiler has detected that water is not circulating correctly through your radiators and pipework, causing an unusual temperature difference.
Your boiler has detected that its two internal temperature sensors are giving very different readings, suggesting water is not circulating properly or a sensor has failed.
Your boiler has sensed a confusing temperature difference between its internal sensors, causing it to shut down for safety.
Your boiler has detected an unusual temperature difference between internal sensors, which often means the water isn't flowing correctly.
Your boiler has lost the ability to monitor its own water pressure, meaning it has shut down as a safety precaution.
BoilerFaultCodes