97 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal computer system is having trouble talking to its main control unit, meaning the appliance cannot tell itself to heat your home or water.
Your boiler has lost the ability to 'talk' to its display, meaning it cannot receive commands or show you what it is doing.
This is a settings menu adjustment that controls the maximum power your boiler uses for heating, rather than a mechanical failure.
Your boiler is simply finishing its normal cooling down cycle after a period of heating, which is a standard operational state and not a fault.
Your boiler is taking a temporary break to prevent itself from turning on and off too frequently, which helps save energy and protect its internal components.
Your boiler is currently in a brief, automatic resting period between heating cycles to prevent excessive wear on the system.
Your boiler is displaying the current temperature of the water inside your hot water storage cylinder.
Your boiler is currently displaying the target temperature it is trying to reach for your radiators; this is an information status code rather than a fault.
Your boiler is displaying the current temperature setting for your hot water tank rather than a fault code.
Your boiler is operating normally but is currently showing whether your external room thermostat is telling the heating to be on or off.
Your boiler is simply displaying the target temperature being requested by your external room thermostat or smart control system; this is a status message rather than a breakdown.
Your boiler is currently showing the status of its internal pump while it circulates water through your radiators.
Your boiler is currently reporting the operational status of an internal pump used to help circulate water through your radiators.
Your boiler is displaying the current operating status of your external hot water pump rather than an actual error message.
Your boiler is currently set to a configuration mode that requires an adjustment to how water is circulated through your heating system.
This is a normal status message showing whether your external thermostat is currently telling the boiler to turn the heating on or off, rather than a genuine fault.
Your boiler is currently set to manage its operation based on the temperature of the water returning from your radiators rather than the water leaving the boiler.
Your boiler is not currently experiencing a fault; it is simply showing a status message to indicate the internal pump is cooling the system down after use.
Your boiler is notifying you of the maximum temperature your hot water is allowed to reach, usually based on your current settings.
This is a normal status message showing whether your central heating is currently requested to be on or off; it is not a system fault.
Your boiler is currently reporting whether the internal water pressure switch is active or inactive, which is part of its normal checking process but may indicate an issue if the boiler stops working.
Your boiler is currently receiving a signal from your thermostat to heat your hot water cylinder or prepare for hot water delivery.
Your boiler's internal control switch is not communicating correctly with connected parts like a pump or external valve, preventing it from starting up properly.
Your boiler is notifying you of a specific settings or wiring issue within an optional plug-in accessory module used to control extra components like pumps or external valves.
Your boiler is currently telling you how it is set to refill its water pressure, rather than indicating a breakdown or a dangerous fault.
Your boiler is struggling to control its internal fan speed, which is preventing it from safely moving air through the system to start the heating process.
Your boiler is displaying the current fan speed for diagnostic purposes rather than an error, but it may indicate an issue with how the fan is communicating with the system.
Your boiler is displaying the current water temperature being sent to your radiators, which is a normal status message rather than an error fault.
Your boiler is displaying the temperature of the water returning from your radiators to help you monitor its efficiency.
Your boiler is confused because it is receiving conflicting instructions regarding how hot the radiators should be based on the outside temperature.
This is not an error code, but a technical setting that allows you to adjust the temperature at which your heating system starts operating.
Your boiler is struggling to read the outdoor temperature, which may affect how efficiently it balances your heating based on the weather outside.
Your boiler is displaying an internal message regarding how slowly the fan is spinning, which usually means the system is attempting to calibrate itself but may need a professional adjustment.
Your boiler is adjusting its fan power settings to maintain a safe and stable flame.
Your boiler is notifying you that it is currently using extra heat to prevent your solar heating system from getting too cold.
Your boiler has paused heating because it is detecting a temperature change that is too rapid or unusual, often caused by a restriction in water flow.
This is an information code rather than a fault, showing you a history of how many times the boiler has successfully started up.
Your boiler is currently running at a lower temperature because your heating controls have told it to enter an energy-saving night mode.
Your boiler is providing a status update about how long it takes for the flame to light, which may indicate it is starting to struggle during ignition.
Your boiler is taking longer than it should to light the flame, which is preventing the heating from starting up properly.
Your boiler is currently pre-heating water so that it is available more quickly when you turn on your hot tap.
Your boiler is taking a planned short break between firing cycles to prevent inefficient operation and internal wear.
Your boiler is struggling to light the flame on its first try, which could lead to it locking out and leaving you without heating or hot water if it continues.
Your boiler is struggling to light its flame and is failing to stay on regularly, which may leave you without heating or hot water.
Your boiler's heating temperature has been set to a limit that is too high for the system to safely handle, often resulting in an automatic shutdown to prevent overheating.
Your boiler is taking longer than it should to heat up your hot water tank, meaning the water may not be reaching the desired temperature efficiently.
Your boiler is struggling to efficiently heat your hot water cylinder, likely due to a poor connection or an incorrect settings configuration.
Your boiler's memory of past errors has been successfully cleared and it is now operating normally.
Your boiler is currently reverting its internal settings back to the manufacturer's original state.
Your boiler has lost its connection to the sensor that measures how hot the water is inside it, preventing it from heating your home safely.
Your boiler has lost its connection to the sensor that monitors the water temperature returning to the unit, causing it to shut down for safety reasons.
Your boiler has stopped working because a sensor that monitors water temperature has developed a faulty faulty connection or failed completely, causing the system to shut down for safety.
Your boiler has stopped working because a sensor that measures the temperature of water returning to the system is providing an incorrect signal, causing a safety shutdown.
Your boiler is struggling to read the temperature of your hot water cylinder because a sensor or its connecting wire has developed a fault.
Your boiler is having trouble detecting the temperature of your hot water, which means it may struggle to provide a consistent hot shower or turn off the tap water heating properly.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected that the water is heating up significantly faster than it can move around the system, so it has safely turned itself off to prevent overheating.
Your boiler has detected that the water inside is heating up far too quickly for the system to handle, so it has shut down to prevent damage.
Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent overheating or fire risk.
Your boiler has detected an internal error where it mistakenly believes a flame is present when the burner is actually turned off, preventing it from starting safely.
Your boiler is trying to start up but cannot successfully light the flame needed to heat your water.
Your boiler has stopped because the flame inside has gone out and will not stay lit.
Your boiler has detected an issue with the internal ventilation system that helps move exhaust gases safely out of your home, so it has shut down to prevent unsafe operation.
Your boiler's internal communication system is failing to send signals correctly, which is preventing it from firing up.
Your boiler has detected an internal communication error with the gas control system, meaning it will not light because it cannot safely manage your fuel supply.
Your boiler has detected that the internal gas valve is not closing correctly when it should, which prevents the unit from starting safely.
Your boiler's computer memory has encountered an internal error, which prevents it from operating correctly and requires a specialist to reset or replace the main circuit board.
Your boiler's computer is struggling to read internal sensor signals, causing it to shut down to prevent incorrect operation.
Your boiler’s control brain is overheating, which has triggered a safety shutdown to protect the internal electronics from damage.
Your boiler has detected an internal communication error with its flame monitoring system and has shut down for your safety.
Your boiler is struggling to keep the flame lit reliably, causing it to shut down for safety reasons.
Your boiler's computer has lost its internal identification settings, essentially forgetting which specific model it is, which prevents it from operating correctly.
Your boiler is struggling to accurately measure the temperature of the water flowing into your heating system, so it has stopped working to prevent potential damage.
Your boiler has detected an inconsistent temperature reading between its internal pipes, meaning it cannot accurately measure how well it is heating your water.
Your boiler has detected that the internal sensor responsible for monitoring water pressure is sending an incorrect electrical signal, meaning the system may not be able to accurately tell how much water is inside.
Your boiler's internal water pressure gauge is sending a confused signal to the control panel, meaning the system cannot accurately read how much pressure is in the pipes.
Your boiler is not detecting the necessary water movement to safely ignite and provide heating or hot water, usually because the internal system pressure is too low or a sensor is blocked.
Your boiler has detected that it is getting too hot inside and has safely turned itself off to prevent damage.
Your boiler has detected a problem with the system that safely removes waste water or controls exhaust gases, causing it to shut down to prevent damage.
Your boiler has lost the connection to the temperature sensor that controls your hot water, meaning it cannot properly heat the water for your taps.
Your boiler is struggling to detect the expected temperature difference between the water leaving and returning to the system, causing it to shut down to prevent damage.
Your boiler is confused because the temperature readings between different parts of the system don't match, causing it to shut down to prevent damage.
Your boiler's internal temperature probe has been identified as being loose or incorrectly positioned, meaning it cannot accurately read the water temperature to heat your home safety.
Your boiler has lost the signal from the contact sensor that monitors your underfloor heating system, preventing it from heating that specific area.
Your boiler is failing to light the flame properly, meaning it cannot produce heat or hot water.
Your boiler is struggling to control its internal gas flow, which has triggered a safety shutdown to prevent the unit from operating incorrectly.
Your boiler's water circulation system is failing, which means the device cannot move heat around your home effectively.
Your boiler has lost the ability to read the temperature of your hot water cylinder, which means it cannot safely heat your tap water.
Your boiler has encountered a general communication error or internal electronic fault that is preventing it from running properly.
Your boiler is currently running a self-cleaning air removal cycle to clear trapped air from the system pipes.
Your boiler is currently running a professional diagnostic test to check its performance at full power, rather than showing a breakdown fault.
Your boiler is currently performing a routine automated safety check after starting up to ensure it is running efficiently.
Your boiler is performing a routine air-bleeding or check program after being switched on or reset, and it is not currently an error that requires a repair.
Your boiler is currently in a manual filling or draining mode, which is why it is temporarily preventing the heating and hot water from working.
Your boiler is operating normally and is currently running to provide heating to your radiators.
Your boiler is currently working exactly as it should, warming up the water for your taps and shower.
BoilerFaultCodes