23 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 stopped working as a safety precaution.
Your boiler has detected a problem with its primary temperature sensor and has stopped working as a safety precaution.
Your boiler has detected a problem with its primary temperature sensor and has stopped working as a safety precaution.
Your boiler has detected a problem with its primary temperature sensor and has stopped working as a safety precaution.
Your boiler has detected a problem with the temperature sensor that monitors the water returning to the unit, causing it to stop running for safety.
Your boiler has detected a problem with the temperature sensor that monitors the water returning to the unit, causing it to stop running for safety.
Your boiler has detected a problem with the temperature sensor that monitors the water returning to the unit, causing it to stop running for safety.
Your boiler has sensed that the water returning from your radiators is hotter than the water leaving the boiler, which usually means there is a circulation problem or a sensor fault.
Your boiler has detected an issue with the fan, which means it cannot safely move air and gas through the system to start the heating process.
Your boiler has sensed that the water returning to it is significantly hotter than the water going out, which usually means there is a blockage or a sensor error causing the system to stop for safety.
Your boiler is trying to light but cannot spark or maintain a flame, meaning you have no heating or hot water.
Your boiler has shut down because the water inside it has become too hot, causing it to overheat for safety.
Your boiler has shut down because its internal temperature sensors have detected that the exhaust gases are getting too hot, which could damage the system.
Your boiler has detected that the water pressure is too low for it to run safely, or there is a blockage preventing water from circulating.
Your boiler has detected that the fan, which safely removes waste gases, is spinning at the wrong speed or has stopped working entirely.
Your boiler has stopped working because it cannot correctly monitor the temperature of the water leaving the unit.
Your boiler has detected a problem with one of its internal temperature sensors, which prevents it from monitoring the water returning to the unit correctly.
Your boiler's hot water sensor has failed or detected an error, meaning the system cannot accurately measure the temperature of your tap water.
Your boiler has detected a problem with the sensor that monitors exhaust fumes, causing the unit to shut down for safety.
Your boiler is having trouble reading the outside temperature and is unable to adjust your heating efficiently.
Your boiler's electronic brains have encountered an internal software or communication error and can no longer control the heating safely.
Your boiler has detected that the internal temperature sensors have been mixed up or are reading in the wrong order, preventing it from heating your water safely.
Your boiler thinks it sees a flame even though it hasn't started the ignition process yet, which is a safety error that prevents the unit from firing up.
BoilerFaultCodes