64 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Genus ONE
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Your boiler is struggling to accurately measure the temperature of the water used for your radiators, causing it to shut down for safety reasons.
Your boiler's computer brains are having trouble talking to each other, which means the system cannot safely operate and has shut down.
Your boiler has stopped working because it cannot light its internal flame to heat your water.
Your boiler is struggling to clear exhaust gases, so it has safely shut itself down to prevent any risk.
Your boiler has detected a faulty sensor that monitors the temperature of the water used for your taps, causing it to stop producing hot water to prevent overheating.
Your boiler has detected that the water in your hot water cylinder is slightly hotter than the temperature you have set it to.
Your boiler is struggling to accurately detect the temperature of your hot water supply because a connection to a heat sensor has been interrupted.
Your boiler has lost the internal connection needed to communicate with its controls, which usually indicates an electrical fault or a blown fuse inside the boiler casing.
Your boiler has detected that a safety switch is stuck in the wrong position, which prevents it from starting to avoid any risk of incorrect combustion.
Your boiler is struggling to push air through its internal system effectively, preventing it from starting up properly.
Your boiler is struggling to clear exhaust gases because it cannot confirm that the internal fan is moving air effectively, so it has shut down to keep you safe.
Your boiler is struggling to stay lit and has failed to restart after several attempts to create a steady flame.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler is struggling to pump water around your heating system, so it has shut down to prevent damage from overheating.
Your boiler has stopped working because one of its internal temperature sensors is providing an inaccurate reading, causing the system to shut down for safety.
Your boiler has stopped working because a sensor that measures the temperature of the water circulating to your radiators is sending an incorrect signal, causing a safety shutdown.
Your boiler has lost its connection to a temperature sensor, which prevents it from safely heating your home's water.
Your boiler has lost the ability to measure the temperature of your hot water, so it has safely shut down to prevent overheating.
Your boiler has lost its connection to a sensor that measures the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler has lost the ability to measure the temperature of your hot water, so it has safely stopped heating to prevent it from getting too hot.
Your boiler is perfectly fine; it has simply activated its built-in protection system to stop your pipes from freezing during cold weather.
Your boiler has detected that hot water isn't moving around your radiators or taps properly, so it has turned itself off to prevent overheating.
Your boiler is perfectly fine; it is simply running its internal pump to prevent the pipes from freezing because the temperature in the room where the boiler is located has dropped.
Your boiler is failing to light the internal flame needed to heat your water, which means it has safely shut itself down to prevent a gas buildup.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is trying to start up but cannot successfully light the flame, so it has shut down as a safety precaution.
Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage or safety risks.
Your boiler is repeatedly struggling to keep its internal flame lit while it is running, causing the system to shut down for safety.
Your boiler has detected that water is not flowing through the system correctly, which is preventing it from heating your home safely.
Your boiler has detected that hot water isn't moving around your radiators or pipes properly, causing it to shut down to prevent damage from overheating.
Your boiler has detected that the internal fan responsible for safely removing exhaust gases is not spinning correctly, so it has shut itself down to keep your home safe.
The internal computer in your boiler is experiencing a communication error or software glitch, preventing it from managing your heating and hot water correctly.
Your boiler's computer is having trouble communicating internally, which has caused it to shut down for safety reasons.
Your boiler's internal computer is experiencing a major communication error, causing it to shut down to prevent incorrect operation.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has stopped working because it has lost the electronic signal from the sensor that monitors the temperature of the water leaving the unit.
Your boiler has stopped working because a sensor that measures the temperature of the water leaving the boiler is sending an incorrect electrical signal.
Your boiler is currently unable to read the temperature of the water returning to it from your radiators, so it has shut down as a precaution to prevent overheating.
Your boiler has detected an electrical fault in the system that measures the temperature of the water returning to it, causing it to stop heating as a safety precaution.
Your boiler has detected that an external safety sensor, typically linked to your underfloor heating system, has triggered, causing the system to stop working to prevent overheating.
Your boiler has detected a flame signal when it is not supposed to be burning, which is a safety mechanism preventing it from starting.
Your boiler's internal computer has encountered a software internal error and is unable to safely manage the heating process.
Your boiler is struggling to accurately measure the temperature of the water flowing through your system because it has lost communication with its internal thermometers.
Your boiler has failed to start multiple times and has automatically locked itself for safety to prevent a gas buildup.
Your boiler has detected that the main burner is failing to stay alight or ignite properly, resulting in a loss of heating and hot water.
Your boiler is struggling to clear exhaust gases effectively, so it has safely shut itself down to prevent any risk.
Your boiler has detected that no water is circulating through the heating system correctly, causing it to shut down to prevent internal overheating.
Your boiler has detected an issue with the internal airflow, which prevents it from safely igniting and providing heating or hot water.
Your boiler has failed to light the flame properly and has stopped attempting to start for safety reasons.
Your boiler is failing to detect enough water movement inside the system, so it has shut itself down to prevent damage.
Your boiler has detected that the water inside has become dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler failed to light on its first attempt, meaning it is currently unable to produce heat or hot water.
Your boiler has failed to light the flame after trying twice, so it has shut down for safety.
Your boiler is currently unable to sense the temperature of your hot water properly, which means it will stop providing hot water until the faulty sensor is fixed.
Your boiler is struggling to detect the temperature of the water it is trying to heat for your taps and shower, so it has stopped producing hot water to prevent overheating.
Your boiler is struggling to keep the flame attached to the burner correctly, which causes it to shut down for safety reasons.
Your boiler is struggling to detect the temperature of your hot water cylinder, which means it may fail to provide hot water or heat it correctly.
Your boiler is struggling to accurately read the temperature of your hot water cylinder because there is an electrical fault with the sensor cable or the connection.
Your boiler has detected that the water inside its internal storage tank is reaching dangerously high temperatures and has shut itself down to prevent damage or safety risks.
Your boiler is struggling to read the outdoor temperature because the connection to the external weather sensor has been interrupted or damaged.
Your boiler is receiving incorrect information from the outdoor temperature sensor, likely due to a loose wire or a faulty connection outside.
Your boiler’s remote wall controller is having trouble communicating its temperature reading to the heating system.
Your boiler has detected an internal computer error while trying to ignite and has safely shut itself down to prevent any risk.
BoilerFaultCodes