53 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an internal communication error between its internal components, meaning it cannot operate safely and has shut itself down.
Your boiler is displaying a status message related to optional solar water heating equipment, which is usually just an information screen rather than a system fault.
Your boiler is reporting an issue with your home's solar water heating system, which is keeping it from communicating with the main heating unit.
Your boiler's computer is reporting a configuration mismatch between its internal components, meaning it has paused operation to prevent incorrect performance.
Your boiler is displaying a status check of its internal control software, which is usually a temporary communication glitch rather than a mechanical failure.
Your boiler is failing to recognise its internal settings chip, which means it cannot operate correctly until the electronic data connection is restored.
Your boiler's electronic brain is unable to read or recognise the specific configuration key that tells it how to operate your heating system.
Your boiler's internal computer is experiencing a communication or software error, causing it to shut down for safety.
Your boiler's internal computer is reporting an issue with its software configuration that prevents it from starting up correctly.
Your boiler is operating normally and is currently heating your home as requested.
Your boiler is currently just confirming it is working normally and actively heating your hot water.
Your boiler is temporarily pausing to wait for the system temperature to drop, which is a normal protective feature to prevent frequent switching on and off.
Your boiler is perfectly healthy and is simply waiting for you to turn on a tap or adjust your heating.
Your boiler has detected that the water inside the unit is getting hotter than it should be and has switched itself off to prevent overheating.
Your boiler has been accidentally switched into a testing mode used by engineers to check emissions, rather than a sign of a mechanical breakdown.
Your boiler has detected that it has become too hot and has automatically shut down to prevent any internal damage.
Your boiler is trying to start but cannot detect the flame needed to produce heat.
Your boiler has detected an internal error where it believes a flame is present when it should be off, which is a safety lockout preventing the unit from starting.
Your boiler is temporarily pausing between heat cycles to prevent unnecessary wear and excessive fuel use.
Your boiler has detected that a flame is still present even though it has tried to shut off the gas supply, which could indicate a safety issue.
Your boiler's internal computer chip does not match the specific model settings, meaning it cannot communicate correctly to start the heating process.
Your boiler is struggling to accurately read the temperature of the water circulating through your heating system, so it has stopped working as a safety precaution to prevent overheating.
Your boiler's electronic control panel has lost its connection, meaning the main brain cannot communicate with the rest of the system to turn on your heating or hot water.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is simply reminding you that it is due for its regular annual safety inspection and service.
Your boiler is struggling to accurately detect the temperature of your hot water, which means it will likely stop producing hot water until the faulty sensor is replaced.
Your boiler is struggling to detect the current temperature outside, so it is using a default setting to keep your home warm.
Your boiler is currently unable to accurately read the water pressure within the system, so it has safely stopped working to prevent potential damage.
Your boiler has lost signal from the sensor outside your home that measures the temperature, so it is defaulting to a standard operating mode.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, likely due to a loose wire or a faulty sensor connection.
Your boiler has lost the connection to a sensor responsible for monitoring the temperature of the water inside, causing it to stop heating your home to prevent potential damage.
Your boiler has stopped working because one of its internal temperature sensors is giving a faulty reading that suggests a short circuit.
Your boiler has lost its connection to an internal temperature sensor, so it has safely shut down to prevent overheating.
Your boiler has detected that the internal ignition system is staying on longer than it should while the flame is lit, which is causing it to shut down for safety.
Your boiler has detected an internal communication failure within its gas control system, meaning it cannot safely regulate the fuel supply to heating components.
Your boiler is struggling to control the gas supply it needs to heat your home, so it has stopped working for safety reasons.
Your boiler has stopped because the internal flame went out unexpectedly while it was trying to heat your water or home.
Your boiler's computer chip is not communicating correctly with the main control board, preventing it from starting up safely.
Your boiler is struggling to stay lit at a low power setting, which stops it from providing heating or hot water effectively.
Your boiler is trying to start but the flame is failing to establish, which means it cannot produce heat or hot water.
Your boiler has detected that the water temperature readings inside the system are conflicting or missing, causing it to shut down for safety.
Your boiler has detected that water is not flowing through its internal heating system fast enough to operate safely.
Your boiler has detected that water is not circulating properly inside it, which is preventing it from heating your home or water safely.
Your boiler has detected that the water inside the system is becoming dangerously hot, so it has safely shut down to prevent damage.
Your boiler has detected that the water inside isn't moving properly, causing it to overheat and shut down for safety.
Your boiler is overheating rapidly because the water inside isn't circulating properly to carry the heat away.
Your boiler is overheating because water is not circulating through your heating system fast enough, likely due to low pressure or a blockage.
Your boiler has detected that the water temperature is changing in a way that suggests there might be a blockage or a problem with how the water is flowing inside the unit.
Your boiler has detected that water is not circulating correctly through the system or is heating up unevenly, causing it to shut down for safety.
Your boiler has detected that the water pressure in your heating system is dropping significantly faster than it should, which usually points to a leak somewhere in your radiators or pipework.
Your boiler has detected that the water pressure in your heating system is falling away much faster than it should, which usually points to a leak somewhere in your radiators or pipes.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
BoilerFaultCodes