58 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has shut down because the water inside is getting too hot, too quickly, or cannot circulate properly through your heating system.
Your boiler has lost the ability to accurately measure the temperature of the water circulating inside it, so it has shut down as a precaution to prevent damage.
Your boiler has detected that an external safety control, such as a heating programmer or a smart thermostat, is not communicating with or is disconnected from the unit.
Your boiler has switched itself off because it has become dangerously hot inside, likely due to a blockage in the water flow or a mechanical internal fault.
Your boiler has stopped because it cannot keep the internal fire lit, meaning you currently have no heating or hot water.
Your boiler is trying to start up but is failing to light the internal flame, which means you currently have no heating or hot water.
Your boiler's internal computer is struggling to talk to its internal parts, meaning it has paused operations as a safety precaution until the signal issue is resolved.
Your boiler is having trouble breathing because a part responsible for moving air and fumes is not working correctly, which has caused it to shut down for safety.
Your boiler's internal computer is experiencing a configuration error, which prevents it from knowing how to safely operate your heating and hot water.
Your boiler's internal computer is experiencing a communication error, meaning it has forgotten its operating settings and cannot safely start up.
Your boiler's computer is experiencing an internal error, which has safely stopped the unit from running to prevent any unsafe conditions.
Your boiler is having trouble communicating internally, which is causing it to shut down for safety reasons.
Your boiler has detected a communication issue between its internal parts, meaning it has safely switched itself off to prevent further errors.
Your boiler has detected a communication error between its internal electronic parts, causing it to shut down for safety.
Your boiler has lost the chemical signal needed to release gas, so it has safely shut itself down to prevent any unsafe operation.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler's temperature sensor is providing incorrect readings, so it has safely shut down to prevent overheating.
Your boiler's electronic control system is failing to communicate with an external safety sensor or accessory, causing it to shut down to prevent unsafe operation.
Your boiler's internal communication system is experiencing a fault with an add-on device, causing the system to stop working as a safety precaution.
Your boiler has lost communication with an added safety module, meaning it has disabled itself to prevent any potential risks.
Your boiler has detected an internal system error that is preventing it from operating safely, causing it to shut down to protect itself.
Your boiler has detected that the water inside the heating system has become too hot and has automatically shut down to prevent damage.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler is failing to detect the expected temperature rise after the flame ignites, which means it cannot safely heat your water or radiators.
Your boiler has stopped working because it failed to keep its internal flame lit while trying to heat your home.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety.
Your boiler has stopped working because it cannot light its internal flame to heat your water or radiators.
Your boiler is failing to light because it cannot detect a stable flame or is not receiving the gas it needs to stay running.
Your boiler is trying to start but the flame is not catching, meaning you currently have no heating or hot water.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning correctly, so it has shut down to keep your home safe.
Your boiler's internal computer is unable to talk to its control panel, meaning the system has safely shut down to prevent incorrect operation.
Your boiler has detected an internal communication or unexpected electronic fault that is preventing it from starting up safely.
Your boiler is having trouble communicating with an external safety device, such as a carbon monoxide alarm or a specialized shut-off sensor, causing it to stop operating as a precaution.
Your boiler has detected an issue with the electrical connection to the internal gas control system, meaning it cannot safely ignite.
Your boiler's temperature sensor is sending an incorrect or missing signal, which causes the system to stop heating for safety reasons.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to pump water around your heating system correctly, which is preventing it from staying on safely.
Your boiler has attempted to light the flame but has failed to stay on, so it has shut itself down for safety.
Your boiler's temperature sensor is failing to provide accurate readings, which has caused the system to shut down for safety.
Your boiler is failing to ignite because it cannot receive or burn gas properly.
Your boiler has stopped working because it is not receiving a steady supply of gas to keep the flame lit.
Your boiler is having trouble measuring water temperatures, causing it to shut down for safety reasons to prevent overheating.
Your boiler has detected an issue with the internal ventilation system that removes exhaust gases, so it has safely shut itself down to prevent unsafe operation.
Your boiler has detected that hot water is not flowing correctly through your heating system, so it has shut down to prevent damage.
Your boiler is currently unable to sense the temperature of your hot water, which means it has stopped providing it to prevent system errors.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has stopped because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to move water through its internal system effectively, preventing it from heating your home or water properly.
Your boiler has detected that there is not enough water flowing through the system, meaning it has switched itself off to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the water it is heating, so it has safely shut down to prevent overheating.
Your boiler is failing to light because it cannot detect a flame or is not receiving a consistent supply of gas.
Your boiler's air circulation system is currently unable to operate, meaning the boiler has temporarily shut down for safety reasons.
Your boiler has detected trapped air inside the system, which is preventing water from circulating properly to heat your home.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler's temperature sensor is providing incorrect data, so it has safely shut down to prevent overheating while it cannot accurately monitor the water temperature.
Your boiler has detected that the water pressure inside your heating system is too low to operate safely.
BoilerFaultCodes