25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a problem with its primary temperature sensor and has shut down as a safety precaution to prevent overheating.
Your boiler has detected a problem with its primary temperature sensor and has shut down as a safety precaution to prevent overheating.
Your boiler has detected a problem with its primary temperature sensor and has shut down as a safety precaution to prevent overheating.
Your boiler has detected a problem with its primary temperature sensor and has shut down as a safety precaution to prevent overheating.
Your boiler has detected a problem with its internal temperature sensors, which means it cannot accurately monitor the water temperature and has stopped working for safety.
Your boiler has detected a problem with its internal temperature sensors, which means it cannot accurately monitor the water temperature and has stopped working for safety.
Your boiler has detected a problem with its internal temperature sensors, which means it cannot accurately monitor the water temperature and has stopped working for safety.
Your boiler has detected a problem with its internal temperature sensors, which means it cannot accurately monitor the water temperature and has stopped working for safety.
Your boiler has lost connection to its outdoor thermometer because the wiring has developed a fault or been damaged.
Your boiler's fan is failing to maintain a steady speed, which prevents the system from safely drawing in air and exhausting gases.
Your boiler's internal control board cannot safely operate the gas valve, preventing the system from firing up for heating or hot water.
Your boiler has detected a fault with its internal temperature sensor, meaning it cannot safely measure the heat of the water and has stopped working as a precaution.
Your boiler has stopped working because one of its internal heat sensors has developed a fault and can no longer read the temperature correctly.
Your boiler has stopped working because its internal temperature sensor cannot send information to the main control board.
Your boiler has stopped working because it cannot detect a signal from the internal sensor that monitors the temperature of your hot water.
Your boiler has stopped working because an internal temperature sensor that monitors your hot water or heating has developed an electrical fault.
Your boiler has stopped working because it cannot communicate with the internal sensor that monitors your hot water temperature.
Your boiler has detected that the exhaust gases are getting too hot or there is a fault with the temperature sensor, causing the system to shut down for safety.
Your boiler has stopped working because it cannot detect a stable signal from the sensor that monitors exhaust gases, often due to a loose wire or a faulty internal component.
Your boiler has detected a fault with the sensor that monitors water returning from your radiators, preventing the system from heating up safely.
Your boiler has stopped working because one of its internal temperature sensors has lost its electrical connection or developed a fault.
Your boiler has stopped providing hot water because the internal sensor that monitors water temperature has developed an electrical fault.
Your boiler's hot water sensor has failed or become disconnected, meaning the system cannot tell how hot your water is and has stopped heating it for safety.
Your boiler has lost connection with the sensor that monitors the outdoor temperature, which might cause it to heat your home inefficiently.
Your boiler has lost its connection to the outside temperature sensor, meaning it cannot automatically adjust its performance based on the weather.
BoilerFaultCodes