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 safely detect a flame or the pipe that drains wastewater is blocked or frozen.
Your boiler is struggling to breathe because the pipe that vents exhaust gases outside or draws in fresh air is blocked or damaged.
Your boiler has detected a flame inside when it should be turned off, which means it is shutting itself down as a safety precaution.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage to the internal components.
Your boiler has detected that the internal mechanism responsible for safely clearing exhaust gases is not working, so it has shut down to prevent unsafe operation.
Your boiler has detected that the internal water pressure is either too low or the sensor measuring it is faulty, which safely stops the system from running.
Your boiler is having trouble measuring the water pressure or flow inside the system, which usually stops it from working properly.
Your boiler is having trouble detecting the flow and pressure of water moving through the system, which typically stops it from working properly.
Your boiler is struggling to accurately measure the temperature of your hot water, which usually means it will stop heating the water properly.
Your boiler has detected that the water temperature inside is rising too fast or there is a major temperature difference between the pipes, so it has safely shut down to prevent overheating.
Your boiler has detected an issue with the sensor that measures the temperature of the water returning from your radiators.
Your boiler has temporarily stopped working because it has detected an unusual difference in temperature between the water leaving and returning inside the system.
Your boiler has detected a faulty temperature sensor on the main heating circuit, meaning it cannot accurately read the water temperature.
Your boiler has temporarily stopped working because it has detected an issue with an internal temperature sensor.
Your boiler has temporarily stopped working because the temperature inside the exhaust pipe has become too hot.
Your boiler has detected that its main internal heating component requires cleaning or maintenance to continue operating efficiently.
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