28 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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The main computer inside your boiler has lost its connection with the internal components, meaning it cannot send or receive instructions to heat your home.
Your boiler has failed to light or stay lit and has locked itself out for safety.
Your boiler has detected a flame when there shouldn't be one, which means the system has shut down for safety reasons.
Your boiler has switched itself off because it has detected that the water inside has become too hot, acting as a safety precaution to prevent damage.
Your boiler has stopped working because it cannot properly detect the flame needed to heat your water.
The boiler's flame sensor is not working correctly, causing the system to shut down for safety because it cannot confirm if the gas has ignited.
Your boiler is having trouble detecting the flame needed to heat your water, so it has shut down as a safety precaution.
Your boiler has stopped working because it cannot correctly detect the flame it needs to stay lit safely.
Your boiler has detected a problem with its internal fan or the way it clears exhaust fumes, causing the system to shut down for safety.
Your boiler has detected that the water pressure is incorrect or the sensor that monitors it has stopped working properly.
Your boiler has detected that the water pressure is too low for it to operate safely and has temporarily stopped working.
Your boiler is struggling to accurately monitor the water pressure in the system, which is preventing it from heating properly.
Your boiler has detected an issue with the electrical power supply coming from your mains, meaning it cannot operate safely or reliably.
Your boiler has lost connection with the sensor that monitors your hot water temperature.
Your boiler is having trouble controlling the electrical current to its gas valve, which is preventing it from heating properly.
Your boiler has detected an issue with the flame sensor which is preventing it from heating your water and radiators for safety reasons.
Your boiler has detected that the water temperature is too high or that the sensors measuring heat are giving conflicting readings, causing it to shut down for safety.
Your boiler has detected a problem with the sensor that monitors the water temperature for your main heating area, causing it to stop running as a safety precaution.
Your boiler has detected that the water temperature returning to the unit is either incorrect or too high, which has caused it to shut down for safety.
Your boiler has detected an issue with how the gas is burning, which could lead to unsafe fumes being created.
Your boiler has detected a blockage in the chimney or flue pipe that is preventing exhaust gases from leaving your home safely.
Your boiler is having trouble detecting the flame needed to generate heat, causing it to shut down for safety.
Your boiler has detected that the exhaust gases are getting too hot or the sensor monitoring them has failed, causing the system to shut down for safety.
Your boiler has detected a buildup of debris or sludge in its main heating component, which is reducing its efficiency and potentially causing it to overheat.
Your boiler has detected an unsafe level of carbon monoxide or poor combustion, causing it to shut down for your safety.
Your boiler has detected an unsafe level of carbon monoxide or improper combustion and has shut down for your safety.
Your boiler has detected an issue with the flame and has shut down as a safety precaution to ensure gas is not being supplied without being burned.
Your boiler has been reset too many times in a short period and has now locked itself completely for safety.
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BoilerFaultCodes