43 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's water circulation system is experiencing a fault, which means it cannot move heat around your home efficiently.
Your boiler is struggling to switch between heating your radiators and heating your hot water because a internal physical valve is getting stuck.
Your boiler is having trouble communicating with an extra piece of equipment that controls heating for a specific zone of your home, which may result in that area not heating up properly.
Your boiler is struggling to detect the temperature of your hot water cylinder, which means it may fail to heat your water properly.
Your boiler has detected an issue with the sensor that monitors the temperature of your hot water tank, meaning it cannot properly regulate your hot water supply.
Your boiler is receiving a faulty or confused signal from the weather sensor located outside your home, causing it to struggle with calculating the correct temperature for your heating.
Your boiler has lost the connection to the thermometer installed outside, so it is struggling to calculate how much heat your home needs based on the current weather.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, likely due to a faulty electrical connection or sensor.
Your boiler has detected a critical internal error in its main computer that prevents it from turning on the burner safely.
Your boiler is struggling to detect the flow of water inside it, so it has stopped working to prevent any internal damage.
Your boiler has lost the connection to the sensor that measures the water temperature, so it has safely shut down to prevent overheating.
Your boiler is receiving gas at a pressure that is too high, which could be dangerous and requires a professional to stabilise.
Your boiler has detected an incorrect electrical signal from an internal temperature sensor, causing it to stop heating your home as a safety precaution.
Your boiler has lost the connection to the temperature sensor that monitors the main heat exchanger, so it has shut down to prevent overheating.
Your boiler is struggling to accurately read the temperature of your hot water tank because a wire or sensor has stopped working correctly.
Your boiler has lost the connection to the temperature sensor in your hot water tank, meaning it cannot accurately judge when to heat your water.
Your boiler is unable to read the temperature of the water flowing through it because of a faulty connection or component, so it has shut down to prevent damage.
Your boiler is unable to read the temperature of the water flowing through your heating system, which means it cannot safely heat your home or water.
Your boiler has stopped working because it failed to ignite, meaning you currently have no heating or hot water.
Your boiler's computer is having a internal communication breakdown and cannot process instructions properly.
Your boiler is having trouble 'talking' to its internal pump, which means it cannot flow water around the system to heat your home.
Your boiler has paused its initial setup process because the automatic air-venting sequence has not finished successfully.
Your boiler is currently stuck in an incomplete setup mode, meaning the installation process wasn't fully finished or the system hasn't been properly coded.
Your boiler has not been fully configured for operation or there is a communication problem between the internal controls and the burner assembly.
Your boiler has failed to complete its initial setup process, meaning it hasn't properly cleared air from the system or finished its first startup sequence.
Your boiler has detected a signal error from one of its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has stopped working as a safety precaution.
Your boiler has likely been left in a testing mode used during installation or there is a fault with the gas ignition valve.
Your boiler has failed to light the flame needed to heat your home and has automatically shut down for safety.
Your boiler has detected a flame or an electrical signal suggesting a flame is present when the burner is actually turned off, so it has safely locked itself to prevent a potential fire risk.
Your boiler is continuing to detect a flame even after it has been told to shut down, which is a safety precaution to prevent gas issues.
Your boiler’s main computer has detected a serious internal fault that prevents it from operating safely or correctly.
Your boiler has detected that the exhaust gases leaving your home are becoming dangerously hot and has shut itself down to prevent damage.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent permanent damage.
Your boiler is detecting a flame when it shouldn't be, so it is refusing to start for safety reasons.
Your boiler has attempted to start, but it has failed to detect a flame, so it has safely shut itself down to prevent a gas buildup.
Your boiler is struggling to confirm that air is flowing correctly through its internal system, which prevents it from safely starting the burner.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from running safely.
Your boiler has detected that a safety valve responsible for shutting off the gas supply is not closing as quickly as it should.
Your boiler is failing to start because the internal fan that pushes air and gases through the system isn't spinning fast enough to light the flame safely.
Your boiler is unable to start up correctly because the internal air fan is spinning faster than it should during the initial safety check.
Your boiler has detected an issue with the internal ventilation system that pushes gases out, so it has safely shut down to prevent unsafe operation.
Your boiler's main internal computer has detected a serious internal error and has stopped the burner from operating to ensure safety.
Your boiler's computer is having trouble communicating with its internal settings, which has caused it to stop working for your own safety.
BoilerFaultCodes