125 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that parts of its internal system are getting too hot and has automatically shut down to prevent damage.
Your boiler is struggling to accurately detect the water pressure inside the system, which is preventing it from firing up safely.
Your boiler is struggling to move water around your heating system, likely because the pressure is too low or a valve is blocking the flow.
Your boiler is struggling to push water through your heating system, usually because there is trapped air, a blockage, or a pump failing to circulate the water.
Your boiler is struggling to push water around your heating system because the flow is too restricted or the pressure is too low.
Your boiler is struggling to move water around your heating system correctly, which is preventing it from working as it should.
Your boiler is struggling to move enough water through your heating system, usually because there is trapped air, a blockage, or the system pressure is too low.
Your boiler has detected that the water pressure inside the system is too low to operate safely.
Your boiler has detected that the water pressure inside your heating system is too high, which can put unnecessary strain on the internal components.
Your boiler has lost the ability to read the temperature of the water circulating through your radiators, so it has safely shut down to prevent overheating.
Your boiler has lost the ability to read the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler is having trouble communicating with the outdoor weather sensor, which means it cannot automatically adjust your heating based on the temperature outside.
Your boiler is struggling to accurately detect the temperature of the water being sent to your radiators, so it has stopped working as a safety precaution.
Your boiler has detected that water is not moving around your heating system fast enough, triggering a safety shut-off to prevent overheating.
Your boiler is struggling to move enough water through your heating system, which usually means there is a blockage, air trapped in the pipes, or a pump struggling to work.
Your boiler is struggling to move water around your heating system effectively, usually due to low pressure or trapped air.
Your boiler is struggling to detect the temperature of your hot water supply because a connection to one of its internal sensors has been lost.
Your boiler is having trouble reading the water temperature in your storage tank because a sensor connection is interrupted or broken.
Your boiler is struggling to detect the temperature of the water in your separate hot water cylinder, preventing it from heating up your tap water properly.
Your boiler is having trouble communicating with the solar energy system because a heat sensor is disconnected or faulty, which may stop the solar panel integration from working correctly.
Your boiler is having trouble reading the temperature of the water heated by your solar panels, likely due to a loose wire or a faulty sensor connection.
Your boiler has detected that the solar water heating system connected to your home is getting too hot.
Your boiler has detected that the external conditions are cold enough to risk freezing, so it is temporarily running its protective systems to keep internal parts from being damaged by ice.
Your boiler's computer memory has encountered a software glitch, preventing it from functioning correctly.
Your boiler's internal computer is unable to send signals between its main parts, causing the system to stop working reliably.
Your boiler's internal computer is experiencing a software or communication error and has shut down to prevent incorrect operation.
Your boiler has been manually reset too many times in a short period and has now locked itself to prevent potential damage.
Your boiler's internal computer is experiencing a temporary software glitch and cannot communicate with its own systems properly.
Your boiler's internal computer is experiencing a communication failure or software glitch, preventing it from starting up correctly.
Your boiler's internal electronic brain has encountered a processing error and cannot safely operate your heating or hot water.
Your boiler is struggling to read the temperature correctly because it has lost its connection to the room thermostat or internal sensor.
Your boiler has stopped working because it cannot detect a flame, meaning it is currently unable to safely ignite or stay lit to provide heating and hot water.
Your boiler has detected internal flame activity whilst it is instructed to be off, which is a significant safety concern that requires an immediate professional check.
Your boiler is failing to keep the flame stable during operation, which stops the system from heating your water or home safely.
Your boiler has failed to light the flame on the first attempt, which usually happens because there is an issue with the gas supply or the ignition system.
Your boiler has failed to fire up twice and has now locked itself out as a safety precaution while trying to light the flame.
Your boiler is struggling to keep the flame attached to the burner correctly, causing it to cut out for safety reasons.
Your boiler has stopped working because the mechanical fan responsible for pushing out exhaust gases is not spinning at the required speed.
Your boiler is struggling to clear exhaust gases properly, so it has safely shut itself down to prevent any risk.
Your boiler has detected that the internal fan is not operating correctly, preventing it from safely clearing exhaust gases.
Your boiler has detected a break in an internal safety circuit, which is preventing it from firing up to ensure the system remains safe.
Your boiler is struggling to clear air from its system or detect the necessary airflow to start safely, which is preventing it from firing up.
Your boiler has lost the connection to the temperature sensor for your secondary heating zone, which may prevent that specific part of your home from heating up properly.
Your boiler is having trouble communicating with the temperature sensor for your secondary heating area, which may cause that specific part of your home to lose heating control.
Your boiler is having trouble communicating with one of the heating zones in your home, which means that specific area may not be receiving heat as expected.
Your boiler is having trouble communicating with the heat sensor for an secondary heating zone, which may prevent that specific area of your home from heating up correctly.
Your boiler is having trouble detecting the water flow in one of your heating zones, which may stop that specific area of your home from warming up properly.
Your heating system has detected that the water temperature in your second heating zone has risen above the safe operating limit.
Your boiler has detected that the water temperature in one of your heating zones is higher than it should be, so it has shut down to prevent damage.
Your boiler is struggling to pump water around your heating system, usually because there is not enough water in the pipes or a blockage is preventing the flow.
Your boiler has lost communication with its temperature sensor, meaning it cannot accurately tell how warm your room is and may stop heating your home as a safety precaution.
Your boiler is struggling to pump water around your heating system correctly, which is preventing it from heating your radiators or taps effectively.
Your boiler has lost the ability to measure the temperature of the water being sent to your radiators, so it has shut down to protect the system.
Your boiler is struggling to push air through its internal system effectively, preventing it from lighting safely.
Your boiler has detected that the water pressure inside your heating system has dropped too low to operate safely.
Your boiler has tried to start up but failed to light the flame, so it has shut down as a safety precaution.
Your boiler has detected a flame signal even though it has commanded the gas to turn off, which is a safety concern that requires an immediate check.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent potential overheating.
Your boiler is struggling to keep the flame burning steadily, which means it will stop working to stay safe.
Your boiler is struggling to accurately measure the temperature of the water being sent to your radiators, so it has stopped working for safety reasons.
Your boiler has failed to light the flame after multiple attempts, so it has shut down as a safety precaution.
Your boiler has detected a break in a vital safety circuit and has shut down to prevent potential overheating or hazardous operation.
Your boiler is struggling to talk to its internal control system, which prevents it from safely igniting or providing heating and hot water.
Your boiler has stopped because it failed to keep the burner flame lit during operation.
Your boiler is struggling to read the outdoor temperature, which may cause your heating to run less efficiently or not respond correctly to the weather.
Your boiler's central control computer is experiencing a communication error, which has caused the system to shut down for safety.
Your boiler has stopped heating because a secondary control, typically a floor thermostat or a safety cut-out for underfloor heating, is telling the system to power down.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal systems.
Your boiler has locked itself out because the reset button has been pressed too many times in a short period.
Your boiler has detected that a safety switch associated with your underfloor heating system has tripped or disconnected, causing the system to pause to prevent overheating.
Your boiler is trying to light its flame but failing, or the flame is going out as soon as it starts, so it has shut down for safety.
Your boiler has detected that the internal fan, which is essential for pushing out combustion fumes, is not working correctly, causing the boiler to shut down for safety.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler is failing to detect the electrical signal required to open the gas supply, meaning it cannot ignite to provide heat or hot water.
Your boiler is struggling to direct heat where it needs to go because a motorized internal switch has failed to move into the correct position.
Your boiler is failing to detect a flame, so it has safely shut down to prevent gas from building up inside the unit.
Your boiler is unable to read the temperature of the water flowing into your radiators, which means it has safely shut down to prevent overheating.
Your boiler is struggling to accurately detect the temperature of the water it is heating for your taps and shower.
Your boiler is failing to detect that you have turned on a hot water tap, so it is not igniting to heat the water for you.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is having trouble managing its internal gas supply, which prevents it from firing up correctly to provide heat or hot water.
Your boiler has detected an issue with how it manages the air needed for safe combustion, causing it to shut down to prevent unsafe operation.
Your boiler has detected that it is running too hot and has automatically switched itself off to prevent any damage or safety issues.
Your boiler is struggling to communicate with your room thermostat, meaning it doesn't know when to turn your heating on or off.
Your boiler is having trouble monitoring the temperature of the water returning from your radiators, so it has stopped heating to stay safe.
Your boiler's computer has detected an internal communication error and has safely shut itself down to prevent potential system faults.
Your boiler’s internal computer is experiencing a communication error, meaning it has lost its ability to regulate itself safely and has shut down to prevent damage.
Your boiler's internal computer is experiencing a temporary communication error which is preventing it from functioning correctly.
Your boiler has failed to light the flame three times in a row, so it has locked itself out to prevent a gas buildup.
Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage or safety risks.
Your boiler has detected an issue with the system that removes waste gases, meaning it has shut down to ensure your home remains safe.
Your boiler has detected that the internal system used to drain away water produced during heating is not working correctly, causing the system to stop for safety.
Your boiler's computer is experiencing an internal processing error and cannot safely manage the heating system.
Your boiler's computer is having trouble communicating internally, which has caused it to stop working to ensure your safety.
Your boiler's computer is having trouble communicating with its internal safety systems, which means it has shut down to prevent any unsafe operation.
Your boiler has stopped working because the water pressure inside the system is currently too low to operate safely.
Your boiler is struggling to accurately measure the temperature of the hot water it produces because a sensor is not communicating correctly.
Your boiler has lost the ability to measure the temperature of the water used for your radiators, so it has shut down to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating through your heating system.
Your boiler has lost the signal from one of its internal temperature sensors, causing it to stop heating to prevent any potential issues.
Your boiler's internal sensor that monitors the water temperature returning to the system is reading incorrectly, causing the unit to shut down for safety.
Your boiler has detected a flame even though it is telling the gas supply to shut off, meaning it has triggered a safety shutdown to prevent a hazard.
Your boiler has detected that the electricity supply wires are connected in the wrong order, preventing it from functioning safely.
Your boiler has detected that the internal components responsible for venting waste gases are not working correctly, causing the system to stop for safety reasons.
Your boiler is struggling to detect the necessary airflow to start safely, so it has stopped working to prevent any risk.
Your boiler's internal computer is experiencing a software glitch that is preventing it from starting up correctly.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is currently unable to read the temperature of your hot water supply, so it has safely stopped heating tap water to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of your hot water, which means it will stop heating it to prevent overheating.
Your boiler has lost the ability to read the temperature of the water circulating through your radiators, so it has shut down to prevent overheating.
Your boiler has stopped working because a sensor that measures water temperature is reporting a faulty signal, causing the system to shut down for safety.
Your boiler has lost the 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's sensor that monitors water returning from your radiators is malfunctioning, which is causing the system to stop heating your home as a safety precaution.
Your boiler has detected a flame when it should be turned off, suggesting a potentially dangerous issue that requires immediate attention from a professional.
Your boiler has detected that the electricity supply wires have been connected the wrong way round, which is preventing it from turning on safely.
Your boiler is failing to start because it detects a faulty signal from its internal airflow sensor before the ignition process has even begun.
Your boiler is failing to detect the airflow needed to safely burn gas, so it has shut down to prevent any risk.
Your boiler has blocked itself for safety because it was reset too many times in a short period.
Your boiler is trying to start but cannot detect a flame, meaning it is currently unable to provide heating or hot water.
Your boiler has automatically shut down because the water inside the system has become dangerously hot.
Your boiler has failed to start because it cannot detect a flame, likely due to a gas supply issue or an internal ignition problem.
Your boiler is correctly powered on and is currently in standby mode or ready to provide heating and hot water.
Your boiler has stopped working because it cannot light the internal flame needed to heat your water.
Your boiler's computer memory has encountered a data corruption error, meaning it can no longer remember its settings or operating instructions.
BoilerFaultCodes