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 switched itself off to prevent any damage.
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 is struggling to push water through your heating system effectively, preventing it from heating your home or water properly.
Your boiler has detected that the water is not flowing around your heating system correctly, which is preventing it from heating your home properly.
Your boiler is struggling to move enough water through your radiators or pipes, preventing it from heating your home property.
Your boiler has detected that the water pressure inside your heating system is too high, which can cause internal leaks or force the safety valve to open.
Your boiler is unable to read the temperature of the water flowing through your heating system, so it has safely shut itself down to prevent overheating.
Your boiler has lost its connection to one of its internal temperature sensors, meaning it cannot correctly measure the warmth of the water returning to the system and has shut down as a precaution.
Your boiler is struggling because it has lost the signal from the weather sensor mounted outside your home, meaning it cannot automatically adjust your heating based on the temperature outdoors.
Your boiler has stopped heating because a safety switch connected to your underfloor heating system has triggered, telling the boiler to shut down to prevent overheating.
Your boiler is struggling to accurately read the temperature of the water circulating through your radiators, so it has stopped heating to prevent potential damage.
Your boiler has detected that water is not flowing around your heating system as efficiently as it should be.
Your boiler has detected that water is not moving around your heating system correctly, which is stopping it from working properly.
Your boiler is struggling to move water around your heating system effectively, which is preventing it from heating your home properly.
Your boiler has detected that water is not flowing around your heating system as efficiently as it should be.
Your boiler is struggling to detect the temperature of the water used for your taps and showers because a sensor connection has been interrupted.
Your boiler's computer is having trouble reading its own internal memory, which means it cannot safely coordinate its heating functions.
Your boiler's electronic control panel is having trouble 'talking' to the main internal brain, which has caused the system to stop working entirely.
Your boiler's internal computer is experiencing a central communication failure and cannot operate safely.
Your boiler has been manually restarted too many times in a short period, so it has locked itself for safety to prevent damage.
Your boiler's central control computer is experiencing a communication fault, preventing it from operating safely.
Your boiler's central control computer is experiencing a communication or processing error, which has caused it to shut down for safety.
Your boiler's internal computer is experiencing a communication or processing error and needs to be reset or inspected by a technician to restore function.
Your boiler has reached its pre-set service interval and is simply reminding you that it is time for a routine professional safety check.
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 has attempted to start but detected that no flame has formed to provide heat or hot water.
Your boiler has detected a flame inside when it should be turned off, which is a significant safety concern that requires immediate professional attention.
Your boiler is struggling to keep the flame attached to the burner correctly, which causes it to shut down for safety reasons.
Your boiler has failed its first attempt to light the flame, which means it cannot produce heating or hot water at this moment.
Your boiler has tried to start twice but failed to light the flame, so it has safely shut down to prevent gas from building up.
Your boiler has detected that the flame has gone out unexpectedly while it was running, which has caused it to stop heating to ensure your safety.
Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage to its internal parts.
Your boiler is struggling to push air through its internal system effectively, which prevents it from igniting safely.
Your boiler is struggling to accurately measure the temperature of the water being sent to your radiators, which means the heating system may not work as expected.
Your boiler is having trouble 'reading' the temperature for one of your heating zones, meaning it may struggle to provide heat to that specific area of your home.
Your boiler is having trouble reading the temperature for the third heating zone in your home, which may cause that specific area to stop heating properly.
Your boiler is struggling to accurately monitor the temperature of the water returning to it from your radiators because one of its sensors has stopped working correctly.
Your boiler is having trouble reading the temperature of the water coming back from your secondary heating zone, which may prevent that part of your home from warming up properly.
Your boiler is having trouble reading the water temperature for one of your heating zones, which may stop that specific area of your home from heating up correctly.
Your boiler has detected that the radiator circuit serving your second heating zone is becoming significantly hotter than the system settings allow.
Your boiler has detected that the water temperature in one of your heating zones is getting hotter than it should be.
Your boiler has disabled the central heating system because it can no longer detect or communicate with the equipment that manages how your home is heated.
Your boiler has detected that the water pressure inside the system has dropped too low to operate safely.
BoilerFaultCodes