20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Capriz2
This boiler uses LED flash patterns
Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →
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Your boiler has detected an issue with the sensor that monitors the temperature of the water circulating in your radiators.
Your boiler is struggling to work out the outside temperature because there is a problem with the external sensor or its wiring.
Your boiler has identified a problem with how it moves air and exhaust gases through the system, causing it to shut down for safety.
Your boiler has failed to light or maintain a flame, meaning you have no heating or hot water because the burner has shut down for safety.
Your boiler's hot water sensor has detected a fault, meaning you may experience inconsistent water temperatures or no hot water at all.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has become too hot and has automatically shut down to prevent damage or safety issues.
Your boiler's temperature sensor for the heating system has stopped working correctly, meaning the unit cannot accurately measure how hot the water is.
Your boiler has detected an issue with the hot water temperature sensor, but it will stay running at a slightly lower temperature to ensure you aren't left without water.
Your boiler has detected that there is not enough water pressure in the system to operate safely, causing it to shut down.
Your boiler has failed to ignite, meaning it cannot light the gas to provide heat or hot water for your home.
Your boiler's internal thermometer has stopped working correctly, meaning the system can no longer monitor the temperature of the water used for your heating.
Your boiler is having trouble measuring the temperature of your hot water, which means you may have no hot water at all or the temperature could be inconsistent.
Your boiler has effectively switched itself off because it has detected it was getting too hot, usually caused by a blockage or a pump failure.
Your boiler has detected an issue with how it clears waste gases or a blockage in the drainage pipe, causing it to shut down for safety.
Your boiler is having trouble communicating with the optional outdoor thermometer, which might cause your heating to behave unpredictably.
Your boiler has shut down to protect itself, likely because it got too hot or failed to light the gas flame.
Your boiler has stopped working because the water pressure inside the system is too low for it to operate safely.
Your boiler has switched itself off because the water inside it has become too hot, usually due to a lack of circulation or a blockage.
Your boiler has stopped working because the water pressure is too low for it to operate safely.
BoilerFaultCodes