46 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage to its internal systems.
Your boiler is struggling to move enough water through your radiators, which prevents it from heating your home safely.
Your boiler has detected that water is not moving through your heating system correctly, which is preventing it from heating your home properly.
Your boiler has stopped working because water is not moving through the system quickly enough to prevent it from getting too hot.
Your boiler is struggling to move water through the system, which is causing it to shut down to prevent overheating.
Your boiler is struggling to move hot water around the system, often caused by trapped air or low pressure preventing it from flowing correctly.
Your boiler has lost water pressure and needs to be topped up to work properly again.
Your boiler has too much water inside its system, causing it to shut down to prevent damage from high pressure.
Your boiler has stopped working because it can no longer accurately read the temperature of the water circulating through your radiators.
Your boiler has lost the ability to read the temperature of the water returning to it from your radiators, so it has shut down to prevent potential damage.
Your boiler is having trouble communicating with the outdoor weather sensor, which helps it decide how hard to work based on the outside temperature.
Your boiler has detected that the external temperature safety switch—typically used for underfloor heating—is triggered or disconnected, preventing the system from running safely.
Your boiler has detected a fault with the sensor that measures the temperature of the water being sent to your radiators, which means it cannot heat your home safely.
Your boiler is struggling to move water through the system efficiently, which is stopping it from heating up correctly.
Your boiler is struggling to move water through the system properly, which is causing it to stop running to prevent overheating.
Your boiler is struggling to move water through the system properly, which is preventing it from heating up correctly.
Your boiler is struggling to push water through the system, which is causing it to stop running to prevent overheating.
Your boiler is having trouble measuring the temperature of the water coming from your solar thermal system or incoming supply, which can affect how your hot water is heated.
Your boiler's internal computer memory has encountered a reading or writing error, preventing the system from functioning correctly.
Your boiler's internal computer is struggling to talk to its control parts, preventing it from functioning correctly.
Your boiler’s main internal control board has developed a technical fault, preventing the system from starting up or operating safely.
Your boiler has been manually reset more than five times in fifteen minutes and has temporarily locked itself for safety.
Your boiler's internal computer has encountered a critical error and is unable to communicate with its own internal systems to function correctly.
Your boiler's internal computer is experiencing a communication error and cannot operate, meaning you currently have no heating or hot water.
Your boiler's internal computer is experiencing a communication error and has shut down to prevent potential hardware damage.
Your boiler is simply reminding you that its annual service is due soon to ensure it continues running safely and efficiently.
Your boiler has lost the connection to the temperature sensor that tells it how warm your home is, meaning it doesn't know when to turn the heating on or off.
Your boiler is having trouble communicating with the temperature sensor for your secondary heating zone, meaning that specific area may not heat up correctly.
Your boiler is having trouble communicating with the temperature sensor for one of your heating zones, meaning it doesn't know whether to turn the heating on or off in that area.
Your boiler is failing to light the gas even though it is trying to start up.
Your boiler’s internal safety sensor thinks the burner is still lit even though it should be turned off, which prevents the system from starting safely.
Your boiler is struggling to keep the flame stable, which is preventing it from heating your water or home properly.
Your boiler tried to start up but couldn't create a flame on its first attempt, meaning you likely have no heating or hot water right now.
Your boiler has tried to start twice but has failed to successfully light its internal flame.
Your boiler has stopped during operation because the main burner flame has unexpectedly gone out.
Your boiler has detected that the internal water temperature has become dangerously high and has safely shut itself down to prevent damage.
Your boiler has stopped working because the internal fan isn't spinning fast enough to safely clear away exhaust fumes.
Your boiler has detected a fault with a temperature sensor in your main heating circuit, which may prevent your radiators from warming up correctly.
Your boiler has detected a fault with a temperature sensor responsible for controlling one of your heating zones, which may cause that specific area of your home to stop heating correctly.
Your boiler has detected a fault with a temperature sensor in the third heating zone, meaning it can no longer accurately measure or control the heat for that specific area.
Your boiler is struggling to accurately read the temperature of the water returning from your heating system, which means it cannot heat your home efficiently.
Your boiler is having trouble communicating with the temperature sensor for your secondary heating zone, which may prevent that part of your home from heating up properly.
Your boiler is having trouble reading the water temperature in one of your heating zones, which may stop that specific area of your home from heating up correctly.
Your boiler has detected that the temperature in your secondary heating zone, such as an upstairs floor or an extension, is getting too hot and has shut down as a safety precaution.
Your boiler has detected that the water temperature in one of your heating zones is higher than it should be for safe operation.
Your boiler has disabled all heating areas, meaning your radiators will not warm up until the control system is reset or repaired.
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BoilerFaultCodes