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 how much power the boiler uses for heating your home, rather than a system fault.
Your boiler is continuing to run its internal pump after the heating has switched off to cool down the system, which is a normal operating status rather than a breakdown.
Your boiler is taking a short rest to prevent it from switching on and off too frequently, which protects the internal parts and saves energy.
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 simply displaying the current temperature it is aiming to reach for your central heating; this is an information status rather than a breakdown.
Your boiler is displaying the current target temperature setting for your hot water storage, rather than an error or breakdown code.
This is a status code showing whether your external room thermostat is currently asking the boiler to turn the heating on or off.
This is a status code rather than a fault, simply showing the temperature your external room thermostat is asking the boiler to reach.
Your boiler is currently showing the operational status of its internal pump rather than a fault, meaning the pump is active and circulating water for your heating.
Your boiler is currently reporting on the operational status of an internal pump that helps circulate water through the radiator system.
Your boiler is currently reporting the operational status of the pump that circulates your 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 normal status message showing whether your thermostat is currently telling the boiler to turn the heating on or off, rather than a system 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 unit.
Your boiler is simply showing its current internal setting for how the water pump behaves after heating, rather than reporting a broken part.
Your boiler is limited to a specific maximum temperature for your hot water, which is a setting adjustment rather than a mechanical breakdown.
This is a normal status message showing whether your heating is currently being requested to run by your controls.
Your boiler is checking if the water pressure is within the correct range before it starts heating.
Your boiler is currently reporting whether your thermostat is asking it to pre-heat your water or keep it ready for use.
Your boiler's internal control panel is struggling to communicate with or control an additional accessory or component, such as an external pump or a specific valve.
Your boiler is confused about how it should be using its secondary internal electrical switch, which usually controls external equipment like pumps or ventilation.
Your boiler is notifying you of its current automatic filling system setting rather than indicating a breakdown or safety failure.
Your boiler's fan is not reaching the required speed to safely vent exhaust gases, preventing the system from starting up.
Your boiler is displaying an information code that shows the current speed of the internal fan to help diagnose performance.
Your boiler is checking or displaying the current temperature of the water used to heat your radiators.
Your boiler is displaying an information code rather than an error, simply showing the current temperature of the water returning from your radiators.
Your boiler is notifying you that it is using an automatic setting to adjust its heat output based on the outdoor temperature.
This is a settings menu display showing the starting temperature for your heating system, rather than a physical fault with the boiler.
Your boiler is struggling to accurately measure the weather outside, which may stop it from adjusting your heating efficiently.
Your boiler is warning you that its internal fan is struggling to run at the necessary low speed required for efficient and safe operation.
Your boiler's internal computer is having trouble regulating the fan speed, which is a key part of the combustion process.
Your boiler is receiving heat from an external solar thermal system instead of using gas to heat the water.
Your boiler's temperature sensors have detected an unusual number of overheating incidents and have temporarily limited the system to prevent internal damage.
This is a diagnostic information code showing how many times your boiler has successfully lit, rather than a system fault that requires a repair.
Your boiler is currently operating in a programmed energy-saving mode where it runs at a reduced temperature during the night.
Your boiler is taking longer than expected to light the flame, which could lead to an intermittent loss of heating and hot water if left unaddressed.
Your boiler is struggling to light its burner and is timing out, which means it cannot heat your home or water safely.
Your boiler has simply turned on its 'comfort' feature which keeps water pre-heated so it reaches your taps faster.
Your boiler is temporarily pausing between firing cycles to prevent the burner from turning on and off too frequently, which protects the internal components and improves efficiency.
Your boiler is struggling to light the flame on its first try, which can lead to it failing to provide heating or hot water if it continues.
Your boiler is struggling to light its flame properly and has failed multiple attempts to start up.
Your boiler is notifying you that it has reached the maximum temperature allowed for your heating system, so it is temporarily limiting itself for safety.
Your boiler has timed out because it is taking too long to heat up your hot water cylinder to the required temperature.
Your boiler is struggling to bring your hot water tank up to the correct temperature, likely due to a sensor issue or a problem with the pump transferring heat to the cylinder.
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 electronic or system error that it cannot identify specifically, causing it to shut down for safety.
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 commissioning program typically used during installation or testing, meaning it is not in its normal operating mode.
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