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 and is not producing heat or hot water because it is not receiving fuel or cannot generate a spark.
Your boiler has stopped working because it has detected an incorrect temperature reading and needs to be restarted.
Your boiler has stopped working because the water isn't moving through the system properly.
Your boiler is struggling to accurately track how water is moving through the system, which prevents it from heating up correctly.
Your boiler has switched itself off because it has reached a temperature that is too high, often caused by a circulation problem or a faulty safety sensor.
Your boiler is having trouble measuring the temperature of your hot water, which means your taps and showers may not get warm.
Your boiler has detected an issue where the fan is not spinning correctly or communicating with the system, preventing the boiler from starting for safety reasons.
Your boiler has detected that the temperature near the heating sensor has become too high, causing the system to shut down for safety.
Your boiler has detected that there is not enough water in the system to operate safely, causing it to shut down.
Your boiler has become too hot and has shut down as a safety precaution to prevent internal damage.
Your boiler has detected that there is too much water in the system, which puts extra strain on the internal seals.
Your boiler's internal thermometer for the heating system has stopped working correctly, meaning the unit cannot accurately measure water temperature to run effectively.
Your boiler's computer brain has encountered a software glitch and is unable to run the system correctly.
Your boiler has stopped working because the fan is not receiving the correct amount of electrical power to safely exhaust fumes.
Your boiler has detected that the water flowing back from your radiators is too hot, causing the system to shut down for safety.
Your boiler has shut down because it or the exhaust gases are getting too hot, which is a safety mechanism to prevent damage or dangerous fumes.
Your boiler has detected a problem with the sensor that monitors the exhaust gases, and as a safety precaution, it has stopped running to prevent overheating.
Your boiler has detected a problem with the sensor that monitors the water temperature returning from your radiators, meaning it cannot safely regulate the central heating.
Your boiler's internal heating unit has become so cold that the water inside it has frozen, preventing the system from operating.
Your boiler has detected that there is not enough water pressure or flow to operate safely.
Your boiler has detected that the water used for your taps and shower is getting too hot, causing the system to shut down for safety.
Your boiler has sensed that the exhaust gases are getting too hot and has shut itself down as a safety precaution.
Your boiler has detected that the exhaust gases are not at the correct temperature, causing the system to shut down as a safety precaution.
Your boiler is having trouble 'talking' to your smart thermostat or external controls, meaning it cannot receive the correct instructions to heat your home.
Your boiler has detected that water is not circulating correctly through the system, causing an unusual temperature gap between the pipes.
Your boiler has detected that the temperature sensors are giving conflicting readings, causing it to shut down for safety.
Your boiler has detected an unusual temperature difference between the pipes, causing it to shut down for safety.
Your boiler has stopped working because it cannot correctly detect the water pressure, often caused by a faulty internal sensor.
Your boiler is overheating because the water is not being pumped around the system correctly.
Your boiler has detected an issue with the sensor that monitors water movement, meaning it cannot safely regulate heat or provide hot water.
Your boiler's temperature sensor for hot water has stopped working correctly, meaning your taps might not get warm or the water temperature could be inconsistent.
Your boiler has stopped working because the fan that removes waste gases is not spinning or communicating correctly with the system.
Your boiler has detected that the water inside the heating system is getting too hot and has shut down as a safety precaution.
Your boiler has detected that the water pressure in the system is too low to run safely.
Your boiler has shut down because it has reached an unsafe temperature and needs to cool down before it can operate again.
Your boiler has too much water in the system, which puts extra stress on the internal components.
Your boiler’s internal computer has encountered a glitch or a programming fault that is preventing it from running properly.
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 becoming too hot, causing the system to shut down safely to prevent internal damage.
Your boiler has detected a fault with the sensor that monitors exhaust gases, and it has shut down as a safety precaution.
Your boiler has detected a problem with the sensor that monitors the water temperature returning from your radiators, preventing it from heating your home correctly.
Your boiler has detected that the water inside the heating unit has frozen due to extremely low temperatures, preventing it from starting up safely.
Your boiler has detected that the water used for your taps and shower is getting too hot, so it has shut down to prevent damage or scalding.
Your boiler is having trouble communicating with your external thermostat or heating controls, preventing it from knowing when to turn on.
Your boiler has detected that the water leaving the unit and the water returning to it are at very different temperatures, suggesting a circulation problem.
Your boiler has detected an unusual temperature difference between internal parts, suggesting water isn't moving through the system correctly.
Your boiler has detected an unusual temperature difference between the pipes, essentially getting confused about how hot the water is at different points in the system.
Your boiler has detected an unusual temperature difference between internal sensors and has shut down as a safety precaution.
Your boiler is struggling to accurately measure its internal water pressure, which prevents it from running safely.
BoilerFaultCodes