29 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to light, which means you will not have any heating or hot water until the issue is resolved.
Your boiler has detected an internal temperature issue and has locked itself out to prevent overheating.
Your boiler has sensed that it is getting too hot and has shut itself down to prevent damage or safety issues.
Your boiler's internal thermometer for the central heating system has stopped working correctly, which means the system cannot monitor or control the water temperature.
Your boiler has stopped working because the fan is not receiving the correct electrical power needed to safely clear exhaust fumes.
Your boiler has detected that there is not enough water pressure or flow to operate safely, which is preventing your heating and hot water from working.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot or the sensor itself has failed.
Your boiler has detected that the exhaust gases are not being monitored correctly and has shut down for safety.
Your boiler has stopped working because water is not moving through the system properly, which is causing it to overheat and shut down for safety.
Your boiler has detected an issue with the sensor that monitors water movement, preventing the system from heating up properly.
Your boiler has detected a problem with the sensor that monitors hot water temperature, meaning you will likely have no hot water or inconsistent temperatures.
Your boiler has detected an issue with the fan that clears exhaust gases, preventing the system from starting for safety reasons.
Your boiler has detected that the water temperature in your heating system is getting too high, causing it to shut down for safety.
Your boiler has detected that there is not enough water in the system to operate safely and has shut down to prevent damage.
Your boiler has shut down because it has detected its internal temperature is getting too hot, usually caused by a blockage or a pump failure.
Your boiler has too much water in the system, which puts extra stress on the internal components.
Your boiler's internal computer has encountered a glitch or a configuration error and cannot communicate properly with the system.
Your boiler has detected that the water returning from your radiators is too hot, causing the system to shut down to prevent damage.
Your boiler has sensed that the exhaust gases are becoming too hot and has shut down as a safety precaution.
Your boiler has detected a fault with the sensor that monitors exhaust gases, and as a safety precaution, it will not operate until this is fixed.
Your boiler has detected a problem with the sensor that monitors the water temperature returning from your radiators, preventing the system from operating correctly.
Your boiler has detected that the water inside the main heating unit has frozen due to extremely cold temperatures, preventing it from operating.
Your boiler has detected that the water used for your taps and showers is getting too hot, causing the system to shut down for safety.
Your boiler has lost its digital connection with your external smart thermostat or heating controls, meaning it cannot receive instructions to turn on.
Your boiler has sensed an unusual temperature difference between the water leaving it and the water returning, suggesting that water is not circulating through your heating system correctly.
Your boiler has detected that heat is not moving through the system correctly, usually meaning the water is hotter in one part of the machine than another.
Your boiler has detected an unusual temperature difference between internal parts, suggesting that water is not circulating correctly through the system.
Your boiler has detected an unusual temperature difference between internal sensors, suggesting a possible circulation issue or a faulty component.
Your boiler is having trouble monitoring its internal water pressure, which has caused it to stop working for safety.
BoilerFaultCodes