70 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 detect the water pressure inside the system because the sensor that monitors it is either faulty or unable to get a clear reading.
Your boiler is struggling to move water through your heating system effectively, preventing it from heating your home properly.
Your boiler is struggling to move water through your radiators, likely because the internal pump is blocked or the system pressure is too low.
Your boiler is struggling to push water around your heating system, likely because the radiators are blocked, a valve is shut, or the pump is having trouble.
Your boiler is struggling to move water through your radiators, which prevents it from heating your home properly.
Your boiler is struggling to move water through your radiators, likely because there is air trapped in the system or a blockage preventing proper flow.
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 is struggling to accurately measure the temperature of the water circulating through your radiators, so it has safely shut itself down to prevent overheating.
Your boiler has sensed that water is not flowing through the system correctly, which is preventing it from heating your home safely.
Your boiler is struggling to move water around your heating system effectively, possibly due to trapped air or a blockage.
Your boiler has detected that water is not flowing around your heating system correctly, causing it to shut down to prevent overheating.
Your boiler is having trouble reading the temperature of your hot water storage tank, which means it cannot accurately heat your water.
Your boiler is having trouble communicating with the solar heat sensor, which prevents it from correctly reading the temperature from your panels.
Your solar water heating system has detected that the fluid in your roof panels has become dangerously hot, likely due to a lack of sunlight usage or a system blockage.
Your boiler has detected that the internal water temperature is extremely low and is running its built-in protection mode to prevent the pipes from freezing.
Your boiler's main internal computer has developed a fault and is unable to communicate with the rest of the system, meaning the boiler will not function.
Your boiler's internal computer is struggling to talk to its control parts, preventing it from functioning correctly.
Your boiler's electronic brain is failing to talk to its internal controls, meaning it has safely shut down to prevent incorrect operation.
Your boiler has locked itself out because the reset button has been pressed too many times in a short period, likely due to an underlying fault repeatedly cutting the system off.
Your boiler's internal computer is experiencing a communication error, meaning it has lost track of its own operational state and cannot safely run.
The internal computer that controls your boiler is experiencing a communication error and cannot operate the system safely.
Your boiler's internal computer is experiencing a communication error and has shut down to prevent potential hardware damage.
Your boiler is struggling to read the temperature because the connection to your thermostat or the internal room sensor is faulty or disconnected.
Your boiler is failing to light the internal flame needed to produce heat and hot water, likely due to a gas supply issue, a blocked flue, or a faulty ignition sensor.
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 light the flame to heat your water but was unsuccessful on its first attempt.
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 fan is moving too slowly to safely clear exhaust gases, so it has stopped working as a safety precaution.
Your boiler has detected a break in a safety circuit designed to shut the system down if it overheats, which has caused it to stop working completely.
Your boiler has detected that the internal fan responsible for venting exhaust gases is not spinning or reporting its speed correctly, preventing the boiler from starting safely.
Your boiler is having trouble 'talking' to the temperature sensor for your secondary heating zone, which may prevent that part of your home from heating up correctly.
Your boiler is having trouble reading the temperature in one of your heating zones, which may cause that specific part of your home to lose heating.
Your boiler has lost signal from a temperature sensor responsible for a specific heating zone, which may prevent that part of your home from heating up correctly.
Your boiler is struggling to accurately read the temperature in one of the specific heating areas of your home, which may cause that part of the system to stop warming up correctly.
Your boiler is struggling to detect water flow between its internal heating circuits, which means it will likely stop providing heating and hot water until the faulty sensor is replaced.
Your boiler has detected that the water temperature in your second heating zone is rising higher than it should be, so it has triggered a safety shutdown to prevent damage.
Your boiler has detected that the water temperature in one of your heating circuits has risen too high, so it has purposefully shut down to prevent damage.
Your boiler has detected an issue with the sensor that tracks the temperature of the water circulating through your radiators, causing the system to stop heating safely.
Your boiler's internal computer is having trouble talking to its main control board, which has caused it to shut down to prevent incorrect operation.
Your boiler has stopped working because it cannot light the flame required to produce heat or hot water.
Your boiler has detected that the internal fan responsible for safely exhausting fumes is not spinning or responding correctly, so it has shut down to keep you safe.
Your boiler's temperature sensor is sending an incorrect signal, causing the system to stop working as a safety precaution.
Your boiler is reporting that the water in your hot water cylinder has become slightly hotter than the temperature you have requested.
Your boiler is struggling to detect the temperature of the water being used for your taps, which is preventing it from heating your water properly.
Your boiler has lost its connection to its internal control system or has blown an electrical safety fuse, meaning it cannot operate safely.
Your boiler is failing to register that the internal fan has stopped, likely due to a stuck sensor or internal blockage.
Your boiler is struggling to push air through its internal vent system, which prevents it from igniting safely.
Your boiler is struggling because it cannot detect that it is successfully pulling fresh air in and pushing exhaust fumes out, so it has stopped running to keep you safe.
Your boiler is struggling to stay lit and is repeatedly trying to restart even after ignition has failed.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler is struggling to move water through the system, either because the flow is blocked or the internal pump is not working correctly.
Your boiler has lost the ability to read the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler's temperature sensor is providing an incorrect signal, causing the system to stop heating for safety reasons.
Your boiler has lost its ability to measure the temperature of the water used for your radiators, so it has shut down as a precaution to prevent overheating.
Your boiler is currently unable to provide hot water because it is having trouble reading the temperature of the water coming from your taps.
Your boiler has lost the signal from one of its internal temperature sensors, causing it to stop heating your home as a safety precaution.
Your boiler is struggling to detect the temperature for your hot water supply, so it has stopped providing hot water to be safe.
Your boiler has detected that the temperature is low and has automatically turned itself on to circulate water and prevent your pipes from freezing.
Your boiler has detected that the water is not flowing properly around your heating system, which is preventing it from heating up your home or water.
Your boiler is perfectly safe and is simply running its internal pump to prevent its pipes from freezing during cold weather.
Your boiler has stopped working because it is unable to detect a flame, which prevents it from safely igniting and heating your home.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to the system.
Your boiler has lost water pressure and needs to be topped up to work correctly.
Your boiler is displaying a historical log of the last ten faults that have occurred, rather than a single active error code.
BoilerFaultCodes