81 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's electronic brain is unable to talk to its internal controls, meaning it cannot operate safely.
This is not an error code, but rather a status message indicating the boiler is currently operating at its maximum heating capacity.
Your boiler is simply moving leftover warm water through your radiators to ensure the system cools down safely after a heating cycle.
Your boiler is taking a short rest between heating cycles to protect its internal parts, which is a normal part of its operation.
Your boiler is currently monitoring or displaying the temperature of the water inside your hot water cylinder.
This code is not a fault; it is simply a status message indicating the boiler is calculating the water temperature required to heat your home.
Your boiler is currently communicating with your hot water tank to confirm the temperature it needs to reach for your taps and shower.
This code is not actually an error; it simply displays the current status of your room thermostat to let you know if your heating is being requested to turn on or off.
Your boiler is simply displaying the target temperature currently requested by your room thermostat to confirm it is receiving the signal correctly.
Your boiler is performing a routine check of its internal water pump to ensure the system is circulating correctly.
Your boiler is currently monitoring how water flows through your heating system, and this status message indicates the pump responsible for moving that water is being checked.
Your boiler is notifying you that it is having trouble detecting the movement of water meant to heat your home or provide hot water.
This code is simply a status message showing that your room thermostat is currently telling the boiler that it does not need to provide any heating.
Your boiler is reporting a conflict in how it measures water temperature between the pipes, which is preventing it from heating your home properly.
Your boiler is currently running its automatic cooling sequence to safely distribute residual heat, confirming it is working exactly as it should.
Your boiler is simply reporting that it has reached the maximum temperature allowed for your hot water supply and is operating as expected.
This code is simply a status message confirming that your boiler is currently waiting for a heating demand from your thermostat or timer.
Your boiler's water pressure sensor is reporting that the system has detected an issue with the internal water pressure or the sensor itself is not registering correctly.
Your boiler is simply communicating with your hot water tank or controls to let them know it is ready to heat water when needed.
Your boiler's internal switch that communicates with external accessories like heating pumps or external valves is experiencing a communication error.
Your boiler's internal control system is having trouble communicating with an external accessory, such as an extra pump or a zone valve.
Your boiler is simply displaying a setting configuration for its internal water-refilling feature rather than indicating a breakdown or fault.
Your boiler is struggling to get enough air into its system to burn fuel safely, so it has stopped operating to prevent a hazard.
Your boiler is struggling to detect or control the speed of its internal extraction fan, which prevents it from igniting safely.
Your boiler is reporting an issue with the temperature of the water currently flowing through your heating system, often caused by a sensor reading or a circulation problem.
Your boiler is struggling to accurately detect the temperature of the water returning to it, which may prevent your heating system from working correctly.
Your boiler is simply showing you a setting related to how it calculates the water temperature needed to heat your home based on the outside temperature.
Your boiler is displaying a background setting related to how it calculates the water temperature, but this is an information display for an engineer rather than a functional fault.
Your boiler is struggling to read the temperature from an outdoor weather sensor, which means it cannot automatically adjust your heating performance based on the weather outside.
Your boiler is automatically adjusting its internal air management settings to ensure it burns fuel efficiently.
Your boiler is struggling to automatically adjust the airflow required for proper combustion.
Your boiler is currently waiting for or receiving a signal that your solar thermal water heating system is topping up the temperature of your hot water cylinder.
Your boiler has detected an issue with how it is reading your central heating system's temperature, which may cause it to switch off to prevent overheating.
This code is simply an information display showing the total number of successful times your boiler has lit, rather than an indication of a fault.
Your boiler is currently operating in a low-energy overnight mode, which is a standard feature designed to save fuel while you are asleep.
Your boiler is noting how long it takes to light the flame, which is currently outside of the expected time frame.
Your boiler is failing to light the flame successfully within the time limit allowed, which prevents it from providing heating or hot water.
Your boiler is simply indicating that the 'warm start' feature is currently active, which keeps a small amount of water pre-heated so your hot water arrives at the tap more quickly.
Your boiler is currently in a brief, automatic resting period to prevent excessive wear and tear, and it will start up again on its own shortly.
Your boiler is struggling to light itself on the first try, which means it might take a few attempts to start up or turn your heating on.
Your boiler is failing to start because it has tried and failed multiple times to light the internal flame.
Your boiler is simply displaying the current internal target temperature it is aiming for to heat your home, rather than indicating a faulty error.
Your boiler has stopped trying to heat your hot water tank because it has taken too long to reach the desired temperature, likely due to a system efficiency issue or a blockage.
Your boiler is struggling to heat your hot water tank quickly enough, likely because the sensor or the heating system is not communicating correctly.
Your boiler has stopped working because it has lost the connection to the sensor that measures the temperature of the water inside the system.
Your boiler has lost the signal from one of its internal temperature sensors, causing it to shut down for safety to prevent overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, triggering a safety shut-off.
Your boiler has detected a faulty connection to a sensor that measures the temperature of the water returning to the system, causing it to stop运行 as a safety precaution.
Your boiler has lost the signal from the sensor that monitors your hot water tank’s temperature, so it may stop heating your water to prevent overheating.
Your boiler has detected that it is running too hot and has automatically turned itself off to prevent damage.
Your boiler has stopped working because it does not have enough water inside the system to run safely.
Your boiler has detected that the water inside it is heating up or moving much differently than it should, so it has shut itself down to prevent overheating.
Your boiler has detected that the water inside it is heating up much faster than it should, so it has shut down to prevent damage.
Your boiler has detected that the exhaust gases leaving the system are dangerously hot and has shut itself down to prevent damage or safety risks.
Your boiler has detected a signal suggesting a flame is present when it should be switched off, causing it to shut down for safety reasons.
Your boiler is attempting to start but cannot successfully light the flame to heat your water.
Your boiler is struggling to stay lit because the flame it produces keeps going out while it is trying to run.
Your boiler has detected an issue with its internal air extraction system, meaning it has shut down to prevent unsafe operation.
Your boiler is having trouble communicating with its external controls, such as your thermostat or programmer, due to an electrical signal error.
Your boiler has detected an internal electrical issue that is preventing it from safely controlling the gas flow, so it has shut down to keep your home safe.
Your boiler has detected an issue with the internal gas valve's software or hardware, causing it to shut down for safety reasons.
Your boiler's computer has encountered an internal memory error, meaning it can no longer process instructions correctly and has safely shut down.
Your boiler has detected an internal issue with its electronic control system which is preventing it from operating safely.
Your boiler has detected an internal issue with the temperature monitoring system and has shut itself down to prevent overheating or damage.
Your boiler has detected an issue with its internal electronic monitoring system, causing it to shut down for safety reasons.
Your boiler is struggling to keep the internal flame burning consistently, causing it to shut down for safety reasons.
Your boiler's computer has lost its identity settings, meaning it no longer knows how to communicate correctly with its internal parts.
Your boiler is struggling to accurately measure how hot the water inside it is, so it has stopped working as a safety precaution to prevent overheating.
Your boiler has detected that the water temperature readings at the flow and return pipes do not match as expected, causing the system to stop working to protect itself.
Your boiler's water pressure sensor is sending an incorrect signal, which means the system cannot accurately detect the water level inside the boiler.
Your boiler's internal water pressure sensor is sending an invalid electrical signal, meaning the system cannot accurately read how much pressure is inside.
Your boiler is unable to confirm that water is moving around the system because it cannot detect a change in pressure when the internal pump starts.
Your boiler has detected that it is getting too hot inside and has shut itself down to prevent any damage to its internal parts.
Your boiler is struggling to clear away liquid waste or detected a blockage in the exhaust system, which has caused it to stop working as a safety precaution.
Your boiler is failing to detect water around the heating sensor, which is preventing it from firing up to protect itself from overheating.
Your boiler has detected that the water temperature is significantly different between the input and output pipes, making it unsure if it is operating safely and effectively.
Your boiler has stopped working because it is unable to accurately read the temperature of the water inside the system.
Your boiler has detected that the external sensor or switch connected to your underfloor heating system is not sending a proper signal.
Your boiler is failing to light the flame properly, which means it cannot produce any heat or hot water.
Your boiler is unable to safely control its gas supply, which prevents it from firing up to provide your heating and hot water.
Your boiler is not detecting that water is moving through the system properly, which means it has safely shut down to prevent overheating.
BoilerFaultCodes