37 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is currently in standby mode and is working normally, meaning no fault has been detected.
Your boiler has tried to start up several times but failed to ignite the burner, meaning you currently have no heating or hot water.
Your boiler is struggling to circulate water properly or is heating up too quickly, causing it to shut down for safety.
Your boiler has shut down because it is getting too hot inside, usually caused by a lack of water circulation through the system.
Your boiler has automatically shut down because it detected dangerously high internal temperatures or a potential issue with the gas supply safety valve.
Your boiler has detected an internal safety check failure within its main control board.
Your boiler has detected an issue while monitoring the temperature and performance of the main heat exchanger, causing it to safely lock out.
Your boiler's main internal computer has developed a serious communication fault and can no longer control the heating process safely.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler has stopped working because the internal computer and its sensors are no longer communicating correctly with each other.
Your boiler has detected that a tiny bit of gas may still be burning or sensed after it should have safely shut off.
Your boiler is detecting a flame inside before it is actually trying to ignite, which stops the system for safety reasons.
Your boiler has detected an issue with the internal fan that blows combustion gases safely outside, so it has locked out to prevent unsafe operation.
Your boiler has detected an internal communication or safety response issue and has safely shut down to prevent potential hazards.
Your boiler has detected a problem with the flow of water through the system, meaning it cannot circulate heat properly.
Your boiler is picking up an unusual reading from the hot water storage cylinder temperature sensor.
Your boiler is displaying a status code to show the current temperature of the water being sent to your radiators, which usually indicates normal operation rather than an actual fault.
Your boiler has temporarily stopped working because the water pressure inside the system has risen higher than it should be.
Your boiler has automatically shut down because the water inside it has become dangerously hot.
Your boiler has temporarily stopped working because it cannot properly detect the flow of water inside the system due to a sensor connection issue.
Your boiler's internal sensor that detects water movement has developed an electrical fault, causing the system to stop working as a precaution.
Your boiler has lost the ability to measure the temperature of your hot water, which usually stops hot water from working properly.
Your boiler has detected an electrical fault with the hot water temperature sensor, which means it has temporarily stopped providing hot water to keep the system safe.
Your boiler's computer has detected a serious internal fault that prevents it from operating safely and reliably.
Your boiler has detected a flame even though the gas supply should be turned off, which is a critical safety issue that requires immediate professional attention.
Your boiler has detected that the incoming electricity wires have been wired the wrong way around.
Your boiler has detected that the incoming electricity supply is not running at the correct standard frequency, causing it to lock out for safety.
Your boiler has detected an internal electrical connection issue on its main control board, which causes the system to shut down for safety.
Your boiler has temporarily stopped working because it has lost the temperature reading from the pipe returning water back into the system.
Your boiler has detected a faulty temperature reading inside its internal pipes, so it has safely shut down to prevent any damage.
Your boiler's main computer has suffered an internal error and needs to be reset or inspected by a professional.
Your boiler has automatically turned off because the internal water pressure has dropped too low to operate safely.
Your boiler is temporarily locked out because the water pressure inside the heating system has dropped too low.
Your boiler is operating normally with the correct water pressure while the system is warm or hot.
Your boiler is showing that the internal water pressure is outside the normal operating range, which usually prevents it from working correctly.
Your boiler is displaying an informational status code indicating the temperature of the water being heated for your taps and showers.
Your boiler is simply registering that you have adjusted the hot water temperature control knob on the front panel.
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BoilerFaultCodes