22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal computer is unable to talk to its control panel, meaning the system cannot receive any instructions to turn on.
Your boiler has lost its connection to the external wall-mounted heating controller, meaning it no longer knows when to turn your heating on or off.
Your boiler has lost the digital connection between its main brain and the operating controls, causing it to stop functioning correctly.
Your boiler has stopped working because it cannot light the flame or clear its waste gases, which may be caused by a blocked flue or external venting issue.
Your boiler has detected a flame when there shouldn't be one, or the sensor incorrectly thinks a fire is lit, causing it to shut down for safety.
Your boiler has shut down because it has reached an unsafe temperature, triggered by a safety sensor that prevents the unit from overheating.
Your boiler has stopped working because the fan that removes waste gases is not spinning or communicating correctly with the system.
Your boiler is struggling to accurately measure how much water pressure is inside the system, which is preventing it from firing up correctly.
Your boiler is struggling to detect enough water pressure to operate safely and has shut down to prevent damage.
Your boiler has lost the ability to measure the water pressure accurately, which has caused it to stop running for safety.
Your boiler is struggling to detect the temperature or flow of your hot water properly, which usually means it will temporarily stop providing hot water to your taps.
Your boiler has temporarily stopped working because it has detected an abnormal temperature difference between the water flowing out and returning in.
Your boiler is receiving an incorrect temperature reading from its internal heating sensor, which is causing it to stop operating to prevent potential overheating.
Your boiler has detected that the water temperature coming back from your radiators is too different from the temperature leaving the boiler, which has caused it to shut down to prevent damage.
Your boiler has lost the ability to accurately measure the water temperature in your heating pipes, which prevents it from running your central heating safely.
Your boiler has lost its connection to the sensor that monitors the temperature of the water being sent to your radiators, causing the system to stop heating for safety.
Your boiler has detected that the temperature in the exhaust system is too high, causing it to shut down for safety reasons.
Your boiler has detected that the main part responsible for heating your water is becoming blocked or dirty and needs a professional service.
Your boiler has stopped working because it has failed to start too many times in a row, meaning it has now locked itself out for safety.
Your boiler's internal computer is experiencing a software mismatch, meaning the control board does not recognise the installed firmware version.
The internal clock that schedules your heating and hot water has developed a fault, meaning the boiler cannot keep track of time or follow your programmed settings.
Your boiler is struggling to communicate correctly with your thermostat or external controls, so it has stopped heating to prevent errors.
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BoilerFaultCodes