46 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start up but cannot successfully light the internal flame to produce heat.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has detected an issue with the electrical connection to the internal gas control system, meaning it cannot safely start up to provide heat or hot water.
Your boiler has stopped working because it cannot correctly measure the temperature of the water flowing through your heating system.
Your boiler is having trouble measuring the temperature of your hot water, which means it has stopped providing hot water to your taps and shower.
Your boiler has been manually restarted too many times due to an unresolved issue and has now locked itself for safety.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler is struggling to detect the temperature of your hot water cylinder, which means it may fail to heat your taps or shower correctly.
Your boiler has detected an internal communication or connection error within its control system, preventing it from operating safely.
Your boiler has stopped working because it cannot communicate with the inner fan that clears waste gases, meaning the appliance has safely shut down to prevent unsafe operation.
Your boiler is confused because it senses a flame inside when it shouldn't be there, or it detects a flame when it has not yet commanded the gas to turn on.
Your boiler's control panel detects that one of the buttons is jammed or sticking, preventing it from functioning correctly.
Your boiler has detected that it is heating up significantly faster than it should, so it has safely shut itself down to prevent damage.
Your boiler is struggling to circulate water properly, causing the system to overheat almost instantly, which means it has shut down to protect itself from damage.
Your boiler has detected that a temperature sensor inside the exhaust system is not giving a proper reading, so it has shut down to keep you safe.
Your boiler has lost its digital connection to the wall-mounted thermostat control, meaning it doesn't know when to turn your heating on or off.
Your boiler is failing to start because it is not receiving enough electrical power from your home's mains supply.
Your boiler is struggling to keep its flame lit, so it is automatically turning itself off and trying to restart to keep you safe.
Your boiler is struggling to keep its internal flame lit while it is running, so it has safely shut down to prevent any issues.
Your boiler has lost its connection to the weather sensor that sits on the outside wall of your home, meaning it doesn't know how cold it is outside to adjust your heating automatically.
Your boiler has detected that the exhaust gases are getting too hot and has automatically lowered its power to prevent overheating and potential damage.
Your boiler has lost its wireless connection to the temperature controller, meaning it doesn't know when to turn your heating on or off.
Your boiler is failing to light its internal flame, which means you currently have no heating or hot water until the issue is resolved.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal parts.
Your boiler has detected that the exhaust gases are becoming too hot, so it has safely shut itself down to prevent damage.
Your boiler has detected a general internal fault that is preventing it from operating safely or correctly.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating inside it.
Your boiler is struggling to detect the temperature of the water used for your taps and shower, so it has turned off your hot water to prevent it from getting too hot.
Your boiler has attempted to restart itself too many times after encountering previous faults and has now locked itself to prevent further damage.
Your boiler is struggling to detect the gas flow required to ignite the flame reliably.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler’s internal computer has lost its specific settings, meaning it has forgotten how to correctly manage your heating and hot water.
Your boiler has detected an issue with its internal air extraction system, which is preventing it from lighting safely.
Your boiler has detected what it thinks is a flame inside the unit when the gas is supposed to be turned off.
Your boiler's control panel is struggling to register commands, which is preventing it from starting up or responding to your temperature settings.
Your boiler has detected that water is not moving around your heating system correctly, which is preventing it from heating your home properly.
Your boiler has lost its connection to its external thermostat or control panel, meaning it cannot currently take instructions to turn the heating or hot water on.
Your boiler is struggling because the electrical power it is receiving has dropped below the required level to operate safely.
Your boiler is trying to start but the flame is not staying lit, so it has safely shut down to prevent gas from building up.
Your boiler has tried and failed to light the flame several times and has now locked itself out for safety reasons.
Your boiler has detected an electrical fault in the system that manages the gas supply, meaning it has switched itself off as a precaution to keep you safe.
Your boiler is correctly identifying that the internal mechanism responsible for controlling the flow of gas to the burner isn't receiving the necessary electrical signal, causing the boiler to stop working to ensure safety.
Your boiler has detected an electrical issue with the component that controls its gas supply, which prevents it from igniting safely.
Your boiler's main computer brain is experiencing an internal error and cannot safely operate your heating or hot water.
Your boiler is struggling to clear fumes safely, which has caused it to shut down to prevent the build-up of dangerous gases in your home.
BoilerFaultCodes