62 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to light the internal flame needed to heat your water, so it has shut down as a safety precaution.
Your boiler is detecting a flame inside the unit even though it isn't being asked to heat your home or water, causing it to shut down for safety.
Your boiler has detected that a flame is still present inside the unit even though it should have turned off, which suggests a safety control issue.
Your boiler has stopped working because the internal fan is not spinning fast enough to safely clear waste gases from the system.
Your boiler is failing to light the internal flame needed to heat your water, so it has safely shut itself down to prevent gas from building up.
Your boiler has lost the signal from one of its internal heat sensors, meaning it cannot accurately monitor the temperature and has shut down to stay safe.
Your boiler's hot water sensor is struggling to communicate with the main control board, meaning the system cannot accurately monitor the temperature of your hot water.
Your boiler's hot water storage tank is experiencing a sensor error, meaning it currently cannot accurately detect the temperature of the water inside.
Your boiler has lost the signal from the sensor that monitors your hot water temperature, which means it cannot accurately heat your water.
Your boiler has detected that the internal pump, which pushes heat around your home, is not spinning correctly and the system has shut down to prevent damage.
Your boiler has lost communication with one of its internal control units, meaning it cannot properly manage your heating or hot water functions.
Your boiler has lost track of how hot the water stored inside it is, so it has safely stopped heating to prevent it from overheating.
Your boiler's internal computer has lost contact with the specific memory card that tells it how to operate your particular model.
Your boiler's computer is having trouble communicating with its internal components, causing the system to stop working safely.
Your boiler has lost the ability to communicate correctly with its internal control system, causing the unit to halt operations as a safety precaution.
Your boiler's computer is having trouble communicating internally, which has caused it to switch itself off for safety.
Your boiler's computer is having trouble communicating internally, which is preventing it from starting up correctly.
Your boiler's internal computer is experiencing a communication error, meaning it has lost track of its own settings and cannot safely operate.
Your boiler's main computer brain is having trouble communicating with the ignition system, which means it has safely shut itself down to prevent a potentially unstable start.
Your boiler's fan system is failing to confirm that it is moving air correctly, which stops the boiler from firing up to prevent unsafe operation.
Your boiler has detected that the fan, which pushes waste gases safely outside, isn't slowing down or switching off as it should.
Your boiler is failing to start because it cannot confirm that the internal fan is moving air properly to ensure safe combustion.
Your boiler is struggling to detect the speed at which heating water is returning to it, which will prevent your heating and hot water from working properly.
Your boiler has detected that the water temperature has risen too high and has temporarily shut itself down to prevent damage.
Your boiler is unable to safely drain away the water it creates while running, so it has stopped working to prevent internal flooding.
Your boiler has detected that the internal water storage tank is overfilling, which forces the system to stop working to prevent internal flooding or water damage.
Your boiler has stopped working because it has lost the connection to the sensor that monitors its internal temperature, meaning it cannot safely regulate heat.
Your boiler is currently unable to accurately measure the temperature of the water inside its internal storage tank, which means your hot water supply will not work until this sensor is fixed.
Your boiler has stopped working because it cannot detect the temperature of the water flowing through the system, likely due to a loose wire or a faulty sensor connection.
Your boiler is failing to light the internal burner, so it has safely shut itself down to prevent wasting gas.
Your boiler has detected an internal software or communication error that is preventing it from operating safely.
Your boiler's internal computer is experiencing a software memory error, meaning it cannot process instructions correctly and has shut down for safety.
Your boiler has detected a flame signal even though it is not supposed to be running, which is a serious safety concern as it suggests the gas valve may not be closing properly.
Your boiler is struggling to keep the flame lit once it starts, causing it to shut down for safety.
Your boiler's reset button has been held down for too long, causing the control panel to lock out as a safety precaution.
Your boiler has detected that the internal water storage tank is becoming dangerously hot, so it has safely shut itself down to prevent damage.
Your boiler is sensing a flame even though it hasn't been asked to turn on, which is often caused by moisture or a sensor fault.
Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage or dangerous overheating.
Your boiler is sensing a flame even though the gas should be turned off, leading the system to shut down as a safety precaution.
Your boiler is struggling to accurately measure the temperature of the water inside its internal storage tank, which means it cannot reliably provide hot water.
Your boiler has detected that the internal water storage tank has become too hot and has shut itself down as a safety precaution.
Your boiler has detected that the water storage tank has become too hot and has automatically shut down to prevent damage or safety issues.
Your boiler has detected that it is running much hotter than it should be and has automatically shut itself down to prevent damage.
Your boiler is struggling to drain away the water it creates while running, which causes it to shut down to prevent internal flooding.
Your boiler has switched itself off because it has reached an internally high temperature and needs a manual restart to clear the safety lock.
Your boiler is unable to safely drain away the water it creates during normal operation, causing it to block its own internal system and switch off.
Your boiler's internal pump has stopped circulating water, which means your heating and hot water will not function.
Your boiler has detected an internal safety shutdown because the fan that clears exhaust gases is not running.
Your boiler is failing to ignite the burner at the required power, meaning it cannot provide heating or hot water.
A small cooling fan inside the boiler's control panel has stopped working, which prevents the system from starting to ensure the electronics do not overheat.
Your boiler's internal pump is failing to run its normal cooling-down cycle after you turn the heating off, which could cause the unit to overheat.
Your boiler has switched itself off because the internal fan that clears exhaust gases has stopped working.
Your boiler is failing to circulate water when you turn on a hot tap, meaning you will likely have no hot water.
Your boiler is struggling to switch between providing heating and hot water, meaning you likely have no hot water available.
Your boiler is receiving a request to turn on the heating, but it is failing to respond or light up correctly.
Your boiler is failing to circulate water for your radiators, meaning your heating will not warm up despite being turned on.
Your boiler is failing to light the burner correctly, meaning it cannot heat your home or water.
Your boiler's flame is failing to stay lit or start properly when it needs to run at its lowest power setting.
Your boiler is failing to switch between providing hot water and heating, meaning your central heating may not turn on even when the system is calling for it.
Your boiler has detected that a safety link or internal connector has become loose or disconnected, causing it to stop operating to prevent damage.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler is unable to safely drain away excess water produced during operation, which has caused it to stop working to prevent internal damage.
BoilerFaultCodes