30 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is attempting to start its flame but is failing to do so, meaning you currently have no heating or hot water.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working for safety reasons and requires a professional to identify the internal issue causing the system to shut down.
Your boiler has stopped working because it cannot detect water flowing properly through its internal heating pipes.
Your boiler has detected an issue with the internal ventilation system that prevents it from starting safely.
Your boiler's internal temperature sensor for the heating system is malfunctioning, so the boiler has shut down to prevent overheating.
Your boiler is struggling to detect the temperature outside, which may cause it to run inefficiently or stop your heating from adjusting correctly.
Your boiler has detected a faulty sensor that monitors the temperature of the exhaust fumes, meaning the system has shut down to ensure it is operating safely.
Your boiler has detected that the temperature of the exhaust gases leaving the unit is too high, so it has safely shut itself down to prevent damage.
Your boiler has failed to light the flame properly and has shut down for safety reasons.
Your boiler has detected that water is not moving through the system properly, which has caused it to shut down to prevent overheating.
Your boiler is struggling to circulate water properly, which is preventing it from heating your home or water safely.
Your boiler is confused because two of its internal temperature sensors are either plugged into the wrong spots or the internal water pump has been installed the wrong way around.
Your boiler has stopped working because it cannot accurately measure the temperature of the water circulating inside, meaning it has shut down as a precaution to prevent overheating.
Your boiler has detected that there is not enough water circulating inside the system to heat your home or provide hot water safely.
Your boiler has tried to light several times but failed, so it has shut itself down for safety.
Your boiler has switched itself off because it has detected that the water inside has become or is becoming too hot.
Your boiler has stopped working as a safety precaution and needs to be reset, but if the issue persists, a professional will need to investigate an internal fault.
Your boiler has detected that there is either not enough water in the system or the water isn't moving through the pipes correctly.
Your boiler has detected an issue with the internal air circulation system, which is preventing it from igniting safely.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water flowing through the heating system due to a faulty sensor.
Your boiler is struggling because it has lost the signal from an outdoor thermometer that helps it adjust your heating based on the weather.
Your boiler has detected an issue with the sensor that monitors the exhaust gas temperature, causing it to shut down for safety.
Your boiler has detected that the exhaust gases are becoming too hot, so it has safely shut itself down to prevent damage or overheating.
Your boiler has stopped working because a sensor that measures the temperature of the water returning to the system is failing to send a signal, causing the boiler to shut down as a precaution.
Your boiler has detected that it is dangerously overheating and has automatically shut down to prevent damage.
Your boiler has detected that water is not flowing through it properly, which has caused it to safely shut down to prevent overheating.
Your boiler has detected that two temperature sensors may have been wired into the wrong places or the internal water pump has been installed incorrectly.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water inside the heating system.
Your boiler has stopped working because it cannot detect enough water or water flow inside its main heating pipes.
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BoilerFaultCodes