52 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an internal communication error and has safely shut itself down as a precaution.
Your boiler has failed to light the flame properly and has stopped attempting to heat your home or water for safety reasons.
Your boiler has detected a false flame signal, meaning the system thinks the burner is lit when it should be turned off.
Your boiler has detected that it is not receiving enough water flow to operate safely or effectively.
Your boiler has detected an issue related to the flow of water inside the unit, which has caused it to stop working to protect itself from potential overheating.
Your boiler has failed to ignite or has lost the flame during operation because it is not receiving a consistent supply of gas.
Your boiler has detected an issue with the air supply or exhaust ventilation that prevents it from firing up safely.
Your boiler has detected an issue with the sensors that monitor the water flow, which is preventing it from firing up correctly.
Your boiler has detected a problem with the internal fan that controls the airflow needed to operate safely.
Your boiler has detected an issue with the airflow or exhaust system, meaning it cannot operate safely and has shut itself down.
Your boiler has detected an issue with the air flowing through the flue system, causing it to shut down for safety.
Your boiler has detected an issue with the water pressure sensor, preventing it from knowing if there is enough water to safely heat your home.
Your boiler has detected an issue with the air flowing through the system, preventing it from starting safely.
Your boiler is experiencing a communication failure between the control panel and the main operating system preventing it from firing up correctly.
Your boiler has detected an issue with the air supply or exhaust ventilation system that prevents it from firing safely.
Your boiler has detected an internal communication failure between its main control boards, which prevents it from operating correctly.
Your boiler has detected a communication error between its internal parts, meaning it has safely shut down to prevent incorrect operation.
Your boiler has temporarily stopped working because it cannot safely ignite or maintain a flame.
Your boiler has detected an issue with the internal air or exhaust system that is preventing it from operating safely.
Your boiler is having difficulty communicating with its internal control system, which has caused it to stop working to avoid potential damage.
Your boiler has detected an issue with the water flow or circulation sensor, which is preventing it from heating your home or water correctly.
Your boiler has detected a communication error between its main computer and the internal circuit board, which effectively shuts down the system to prevent incorrect operation.
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 trying to start up, but it cannot get the flame to light properly.
Your boiler is trying to start up, but it is failing to light the gas burner to give you heating and hot water.
Your boiler has tried to start up several times but failed to light the gas flame.
Your boiler has detected that the water inside is getting too hot and may be starting to boil, which is a safety lockout to prevent damage.
Your boiler has detected moisture or combustion gases escaping where they shouldn't be, which requires an immediate professional inspection.
Your boiler has detected that parts of its internal heating system have reached a temperature that is too high, so it has safely shut itself down as a precaution.
Your boiler has detected a potential issue with its safety temperature switch, which ensures the water does not get dangerously hot.
Your boiler has detected that water temperatures inside are incorrect or there may be a serious issue with exhaust gases escaping.
Your boiler has detected that the internal fan responsible for safely clearing exhaust gases is not spinning at all.
Your boiler has stopped working because the internal fan that safely removes combustion gases is not spinning.
Your boiler is confused about how hot the internal water is getting, so it has paused working to keep you safe.
Your boiler is getting confused about how hot the water inside it is getting, so it has paused to keep things safe.
Your boiler has detected that the water flow pipes are connected in the wrong order or that the heat is moving in the wrong direction, causing the system to shut down to prevent damage.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler is struggling to monitor the water pressure in your heating system, so it has safely shut down to prevent potential damage.
Your boiler has detected that the water pressure inside the heating system is too high for it to operate safely.
Your boiler is struggling to accurately read the water pressure inside the system, which is preventing it from firing up safely.
Your boiler is temporarily unable to read the temperature of an external hot water cylinder or secondary tank due to a wiring or sensor fault.
Your boiler's main control computer is experiencing an internal electronic fault, preventing the system from operating correctly.
Your boiler’s internal computer has identified an error in how its internal configuration switches are set, meaning it cannot operate safely until these are corrected.
Your boiler's electronic control panel is experiencing a communication fault, which prevents the display from responding or controlling the unit properly.
Your boiler's computer memory has encountered a serious internal error and can no longer process instructions correctly, meaning the unit cannot operate.
Your boiler's internal clock has lost its settings, which usually means the system cannot keep time to manage your heating schedule correctly.
Your boiler's main computer control panel is failing to process instructions correctly, which has caused the system to stop operating for safety reasons.
Your boiler is struggling to read the temperature outside, which means it cannot automatically adjust your heating to compensate for the current weather.
Your boiler's main control panel is failing to communicate with the internal system, which will prevent your heating and hot water from working properly.
Your boiler is having trouble communicating with your wall-mounted thermostat or smart control system, which prevents it from knowing when to turn on your heating.
Your boiler has detected a minor internal software or communication glitch and needs to be restarted to clear the error.
Your boiler is showing an error because a setting was accidentally changed on the display to the wrong gas type.
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BoilerFaultCodes