23 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because an internal temperature sensor has failed and can no longer monitor the heating water.
Your boiler has shut down because the water inside the heating system has become too hot and cannot circulate properly.
Your boiler has detected that the water temperature is getting too hot while you are trying to use your taps or shower, causing it to shut down for safety.
Your boiler has detected that the exhaust gases are getting too hot, so it has shut down as a safety precaution to prevent internal damage.
Your boiler is failing to light the gas flame required to provide heating and hot water.
Your boiler started to heat up but the flame went out unexpectedly, causing the system to stop working.
Your boiler thinks it sees a flame even when it hasn't started the burner yet, which is a safety conflict that prevents it from firing up.
Your boiler is failing to detect a flame after it tries to ignite, meaning it will not stay lit to provide heating or hot water.
Your boiler has switched itself off because the fan, which manages air and gas flow, is not spinning at the correct speed to operate safely.
Your boiler's main internal computer has developed a technical error and can no longer communicate with the burner safely.
Your boiler has detected a problem with one of its internal temperature sensors, which means it cannot accurately measure heat levels and has stopped working for safety.
Your boiler has detected a problem with one of its internal temperature sensors, which means it cannot accurately measure heat levels and has stopped working for safety.
Your boiler has detected an issue with a temperature sensor that is preventing it from heating your home or water safely.
Your boiler has detected that a temperature sensor is not correctly attached to the internal pipework, preventing it from monitoring heat levels safely.
Your boiler has detected that a temperature sensor is not properly attached or is incorrectly mounted, preventing the system from heating up safely.
Your boiler has detected an internal communication error or a connection issue with a thermal sensor, causing it to shut down for safety.
Your boiler is struggling to breathe because the pipes that take exhaust gases away or bring fresh air in are restricted or blocked.
Your boiler has detected an internal communication error between its main control boards, meaning it cannot operate safely and has shut down.
Your boiler is having trouble reading the outside temperature because the sensor or its wiring has developed an electrical fault.
Your boiler's internal computer has become confused after several reset attempts and has locked itself out for safety.
Your boiler is unable to control the gas supply correctly, which has caused it to shut down for safety.
Your boiler has stopped working because a internal sensor that monitors the temperature of the flue or hot water system has developed a fault.
Your boiler has stopped working because one of its internal heat sensors is reporting a technical error or has failed.
BoilerFaultCodes