130 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is struggling to detect or control the speed of the internal fan that manages the airflow required for safe combustion.
Your boiler has detected an electrical fault within its internal wiring system, which has caused it to shut down for safety.
Your boiler is confused and thinks the flame is already lit before it has actually started, so it is refusing to fire up for safety reasons.
Your boiler is still detecting a flame or heat even though the gas should have been turned off completely.
Your boiler is not firing up because it cannot detect a flame, meaning your heating and hot water will not work.
Your boiler has stopped working because its internal computer settings have been incorrectly configured or have lost their saved values.
Your boiler's electronic control system is being disrupted by electrical interference from a nearby appliance or a faulty power supply.
Your boiler has lost power after a previous fault occurred, which has cleared the original error message and prevented it from restarting.
Your boiler is currently running normally and is in the process of heating up or waiting for a demand for hot water.
Your boiler has detected an internal issue and is alerting you that it requires professional attention to identify the specific problem.
Your boiler's internal computer system has lost communication, likely due to moisture getting into the display panel or electrical interference.
Your boiler has detected an electrical fault in its internal wiring, which has caused it to shut down to prevent further damage.
Your boiler has shut down because the water returning to the unit is too hot, which usually means the water isn't flowing through your radiators properly.
Your boiler has switched itself off because it has detected a dangerously high internal temperature, often caused by a lack of water flow or air being trapped in the unit.
Your boiler has failed to light the flame after repeated attempts to start up.
Your boiler's fan is not communicating correctly with the main control board, preventing the system from starting its safety checks.
Your boiler has stopped working because the internal fan, which safely pushes exhaust fumes away, has failed to start.
Your boiler has detected that water is flowing the wrong way or the temperature sensors are confused, causing it to shut down to prevent damage.
Your boiler has stopped working because it cannot correctly measure the temperature of the water leaving the unit.
Your boiler has stopped working because it thinks the water returning to the unit is too hot due to a faulty internal sensor.
Your boiler has stopped working because it cannot detect the temperature of the water returning to the unit, so it has shut down as a safety precaution.
Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit.
Your boiler is having trouble reading the temperature outside, which may cause it to run inefficiently or heat your home to the wrong temperature.
Your boiler has detected an internal electrical problem and has safely shut itself down to prevent further damage.
Your boiler is currently running at its second, higher-power stage to meet the requested heating or hot water demand.
Your boiler has stopped working because its internal computer settings have been incorrectly configured or corrupted.
Your boiler is operating normally and is currently running at its first stage of heating power.
Your boiler has failed to ignite or lost its flame during operation, and has now shut itself down for safety reasons.
Your boiler has detected that a safety thermostat has tripped, causing it to shut down to prevent the system from overheating.
Your boiler has detected that the water pressure inside the system is critically low, so it has safely shut itself down to prevent damage.
Your boiler has detected that exhaust gases are being blown back into the unit instead of venting safely outside, so it has shut itself down to prevent a fire or carbon monoxide risk.
Your boiler has repeatedly failed to maintain a flame while running and has shut down as a safety precaution.
Your boiler is not receiving any electricity, which means the unit is completely shut down and cannot provide any heating or hot water.
Your boiler is struggling to breathe because the vents or internal airways are blocked, preventing it from safely exhausting fumes.
Your boiler’s internal computer has developed a serious electronic fault and can no longer control the heating safely.
Your boiler has detected that a safety valve is not opening or closing correctly, which means it cannot safely regulate the internal water flow or gas pressure.
Your boiler has failed to light the flame, so it has safely shut itself down to prevent a gas build-up.
Your boiler has stopped working because an internal safety fuse has blown, meaning the control system cannot power up.
Your boiler's internal computer has encountered a critical error and can no longer control the heating system safely.
Your boiler's internal computer has developed a serious communication fault and can no longer control the heating process safely.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler’s internal computer has developed a serious electronic fault and can no longer control the heating process safely.
Your boiler's internal computer brain has developed a critical fault and is unable to manage the system safely.
Your boiler has detected that hot exhaust fumes are being blown back into the machine instead of escaping through your flue, which triggers a safety shutdown to prevent the buildup of dangerous gases.
Your boiler's main internal computer has developed a serious fault and is no longer able to manage the heating process safely.
Your boiler has detected that the internal water pressure or the amount of water inside the unit is insufficient for it to operate safely.
Your boiler has switched itself off because the water inside it has become dangerously hot, likely due to a blockage in the system or a pump failure.
Your boiler has shut down because the water inside its pipes has become hotter than the system is designed to handle.
Your boiler has detected that it is running too hot and has automatically switched itself off to prevent potential damage.
Your boiler is confused because it detects that the water flowing out is cooler than the water flowing in, which is the opposite of how it should be working.
Your boiler is overheating because it cannot move the hot water away fast enough, causing it to shut down to prevent damage.
Your boiler has stopped working because the mechanical fan that pushes exhaust gases out of the flue cannot turn on.
Your boiler's inner cooling fan is failing to turn off, which is usually caused by a loose wiring connection or a faulty communication signal within the unit.
Your boiler has switched itself off because the water inside is not circulating correctly, causing a significant temperature difference between the water heading to your radiators and the water returning to the boiler.
Your boiler has stopped working because a sensor that measures the water temperature is reporting an incorrect or impossible reading, causing the system to shut down for safety.
Your boiler has stopped working because it cannot correctly read the temperature of the water returning to it from your radiators.
Your boiler has stopped working because it can no longer accurately read the temperature of the water flowing through your heating system.
Your boiler has stopped working because it cannot correctly measure the temperature of the water returning to the unit.
Your boiler has lost the ability to accurately measure the temperature of the water circulating back into it, so it has shut down as a precaution to prevent overheating.
Your boiler's computer brain has malfunctioned and can no longer control the heating system safely.
Your boiler's internal computer brain has experienced a critical error and can no longer control the heating system safely.
Your boiler's internal computer settings have become scrambled or corrupted, meaning it no longer knows how to run your heating system correctly.
Your boiler's computer brain has suffered an internal error and cannot communicate with the rest of the system.
Your boiler has detected an issue with the airflow system which prevents it from safely igniting or operating.
Your boiler has temporarily stopped operating because it has detected a specific sequence of internal signals that don't match its safety checks.
Your boiler has paused because the water temperature has risen slightly faster than expected, causing the system to temporarily stop firing as a protective measure.
Your boiler is displaying a status code indicating how it has been configured to manage your heating and hot water settings, but it is not currently indicating a system failure.
Your boiler is struggling to control the speed of its internal fan and will shut down for safety after several failed attempts to start.
Your boiler's fan is struggling to reach the correct speed to clear waste gases, causing the system to shut down for safety after several attempts.
Your boiler is overheating too quickly because water isn't moving through the system fast enough, causing it to take a ten-minute break to cool down.
Your boiler has temporarily paused because an external safety device or control switch has told it to stop running.
Your boiler has switched itself off because the water temperature is rising too quickly, usually due to poor water flow through the system.
Your boiler is overheating because water isn't moving through the system quickly enough, causing it to pause frequently to cool down.
Your boiler's computer settings have been corrupted or changed to values that prevent it from running safely.
Your boiler has paused because an external safety device or switch has told it to stop running for a short period.
Your boiler has detected that the temperature sensors measuring your water flow are reading in the wrong order, likely because the pipes or sensors were installed backward.
Your boiler is detecting that its internal water temperature is rising much faster than it should, so it has shut down to prevent damage.
Your boiler has stopped working because it cannot detect enough water circulating inside the system.
Your boiler is failing to start because it cannot get the internal air-moving fan up to the correct speed to safely prepare for ignition.
Your boiler has detected that the air-intake fan is not spinning at the correct speed and has stopped working to keep the system safe.
Your boiler has detected that the water flowing out to your radiators is significantly hotter than the water returning, suggesting a circulation issue within your heating system.
The internal computer settings for your boiler have been altered, causing the system to stop working because it no longer knows how to run safely.
Your boiler is currently switched off because it is either not receiving a signal to turn on or it is experiencing an electrical power supply issue.
Your boiler is trying to start but cannot maintain a flame, meaning you currently have no heating or hot water.
Your boiler has entered a temporary pause state, often because it is waiting for a command from your heating controls or has been blocked by an external factor.
Your boiler's computer has experienced a memory error, meaning it can no longer process instructions to heat your home.
Your boiler has tried to light several times but has been unable to establish or maintain a flame, so it has shut down for safety.
Your boiler has lost its internal power supply to the main control board, which means it cannot operate your heating or hot water.
Your boiler has shut down because it has detected it is getting too hot, usually caused by poor water flow or a lack of water in the system.
Your boiler is failing to light the burner or keep it lit, which means it has safely shut itself down to prevent gas from building up.
Your boiler has switched itself off because the exhaust gases have become too hot, which usually suggests a blockage or a fault in the flue system.
Your boiler has detected that it is overheating and has automatically shut itself down to prevent damage.
Your boiler is struggling to light or stay lit because it cannot detect a flame, often due to an issue with the gas supply or the ignition components.
Your boiler has stopped working because it can no longer read the temperature of the water circulating inside your heating system.
Your boiler has stopped working because the fan that removes waste gases cannot spin properly, causing the system to shut down for safety.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Your boiler has detected an issue with its airflow and has safely shut down to prevent it from running incorrectly.
Your boiler has detected a communication problem with the internal sensor that monitors water leaving the unit, causing it to shut down as a safety precaution.
Your boiler has sensed that the water inside it is heating up much faster than it is supposed to, causing it to shut down to prevent damage.
Your boiler has stopped working because it cannot correctly read the temperature of the water returning to the unit due to an electrical fault.
Your boiler has detected that the water leaving it is significantly hotter than the water returning, meaning heat isn't circulating properly through your radiators.
Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water returning to the unit.
Your boiler is struggling to move water around your heating system properly, which is causing it to shut down for safety.
Your boiler's main internal computer has developed a serious fault and is no longer able to control the heating process safely.
Your boiler's computer brain has suffered a serious electronic failure and can no longer control the heating system safely.
Your boiler's internal computer has suffered a critical failure and can no longer control the heating process safely.
Your boiler’s internal computer has suffered a critical failure and can no longer control the heating system safely.
Your boiler’s internal computer has suffered a critical failure and can no longer control the heating process safely.
Your boiler's main internal computer has developed a serious fault and is no longer able to communicate with or control the heating system safely.
Your boiler’s internal computer has suffered a critical error and can no longer control the heating system safely.
Your boiler's internal computer has suffered a critical software or hardware failure and can no longer control the heating process safely.
Your boiler has detected that the water inside is getting too hot because it isn't moving through the system quickly enough.
Your boiler has detected that water is returning to the unit too hot, which usually means the water isn't circulating through your radiators properly.
Your boiler is overheating because the water isn't moving through the system fast enough to cool it down.
Your boiler has detected a fault with the hot water temperature sensor, meaning it cannot accurately tell how hot the water is.
Your boiler has lost connection with the sensor that monitors your hot water temperature, which usually means it can't heat your water properly.
Your boiler's internal computer brain is confused by its own settings and needs to be checked and restarted.
Your boiler's computer memory has encountered a software error and cannot confirm its safety settings.
Your boiler has detected an issue with the fan that safely clears exhaust gases, preventing the system from starting for safety reasons.
Your boiler has detected a problem with how gas is being controlled, meaning it cannot safely light or maintain a flame.
Your boiler is correctly sensing a flame when it expects the burner to be extinguished, which is typically caused by a faulty internal sensor or a gas valve that isn't closing properly.
Your boiler has sensed that water is not circulating quickly enough through the system, so it has safely shut down to prevent overheating.
Your boiler has stopped working because it cannot light the flame or keep it burning, requiring a professional to check the gas supply and internal safety sensors.
Your boiler is struggling to keep its internal flame lit, which means it will likely stop providing heating or hot water until the ignition system is serviced.
Your boiler's main internal computer has stopped working correctly and cannot control the heating process.
Your boiler is struggling to keep its internal flame lit, which prevents it from safely heating your water or home.
Your boiler has stopped working because it cannot detect the water level inside the unit, likely due to a loose wire or a faulty sensor connection.
Your boiler is currently running normally and is in its standard operating state.
Your boiler is currently in a manual testing or configuration mode used by engineers to perform maintenance checks.
BoilerFaultCodes