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 setting that limits how hard your boiler works for heating to save energy and match your home's size, rather than a broken part.
Your boiler is currently running its internal pump to cool down after a heating cycle, which is a normal process and not actually a fault.
Your boiler has reached its target temperature and is taking a short rest to prevent it from turning on and off too frequently, which protects the 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 currently reading and displaying the temperature of the water inside your hot water cylinder.
Your boiler is currently showing the target temperature it is aiming to reach for your heating, rather than a fault code.
Your boiler is simply showing the current temperature setting you have chosen for your hot water cylinder.
Your boiler is currently receiving a signal from your thermostat that it does not need to provide any heating.
Your boiler is simply showing the target temperature requested by your room thermostat and is operating as normal.
Your boiler is currently showing you that the internal pump is circulating water around your heating system used for warming your radiators.
Your boiler is currently reporting the operational status of an internal pump used to move water around the heating system.
Your boiler is displaying the current operating status of the pump that circulates hot water, which is a normal information message rather than a breakdown.
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 status indicator showing whether your external room thermostat is currently asking the boiler to provide heating or stay off.
Your boiler is simply displaying whether it is currently regulating its heat based on the water flowing out to your radiators or the water returning to the unit.
Your boiler is currently running its internal pump to cool down or circulate heat, which is a normal setting rather than a malfunction.
Your boiler has reached the maximum temperature limit you have set for your hot water.
This is a normal status indicator showing whether your central heating is currently requested to be on or off, rather than a fault.
Your boiler is checking if the water pressure is high enough to run safely, but it is currently detecting a status that might prevent it from firing up.
Your boiler is currently receiving a signal from your thermostat to heat your stored hot water or maintain the temperature for quicker hot water delivery.
Your boiler's internal control board is having trouble sending a signal to an external component, such as a pump or valve, meaning it cannot operate correctly.
Your boiler is struggling to talk to an internal control switch that handles extra features like pumps or external fans.
Your boiler is notifying you of its current setting for filling itself with water, which is an status update rather than a breakdown.
Your boiler is struggling to bring enough fresh air into the system or clear waste gases out properly, which is stopping it from starting up safely.
Your boiler is displaying a diagnostic message showing its current fan speed, which is a normal status update rather than a failure.
Your boiler is displaying the current temperature of the water heading out to your radiators and is not an error code.
Your boiler is displaying the temperature of the water returning from your radiators rather than showing an error, which is usually part of normal operation.
Your boiler is notifying you that it is using a specific calculated temperature setting to heat your home, typically when an outdoor weather sensor is connected.
This is a settings menu display rather than a fault, showing the starting temperature point for your heating system's weather compensation.
Your boiler is struggling to read the outdoor temperature, which may affect how efficiently it balances your heating.
Your boiler is adjusting its lowest fan speed to ensure it stays running safely and efficiently.
Your boiler is notifying you that it has adjusted its fan speed settings to ensure the gas and air mixture remains at the correct level for efficient operation.
Your boiler is notifying you that a solar panel system is currently being used to pre-heat your hot water.
Your boiler has paused operation because its internal sensors have detected several instances of overheating in a short period.
This is a technical status message indicating the total count of times your boiler has successfully fired up, rather than a system fault.
Your boiler is currently running at a lower temperature because it is in a scheduled energy-saving mode, typically used during the night.
Your boiler is taking longer than expected to light the burner, which may lead to intermittent heating or noise issues.
Your boiler is struggling to light the flame and is timing out before it can get a steady burn established.
Your boiler is simply letting you know that the pre-heat feature is active to provide hot water to your taps more quickly.
Your boiler is taking a temporary, normal breather to prevent itself from turning on and off too quickly, which helps save energy and protect the components.
Your boiler is struggling to light the flame on its first try, which could lead to a complete lockout if the problem continues.
Your boiler is struggling to light the gas flame and has failed to start after multiple internal attempts.
Your boiler is notifying you that the temperature of the water going to your radiators has reached its maximum allowed limit.
Your boiler has taken longer than expected to heat up your hot water tank, so it has timed out for safety.
Your boiler is notifying you that it is currently operating at maximum heat output to warm up your hot water cylinder as quickly as possible.
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 safely.
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 currently running a specific self-test or purging programme usually used during first-time setup or after 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