BoilerFaultCodesYour boiler's main internal computer has encountered a processing error and cannot communicate correctly with the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's internal computer chips stop talking to each other correctly, leading to a total communication breakdown. The most common reason is a physical failure of the circuitry on the main control board or a loose internal data connection that prevents the boiler from safely managing the gas and heat. It is essentially the boiler equivalent of a 'blue screen of death' on a computer.
DIY fix possible
Press the 'Reset' button on the front display onceSwitch the main electrical power to the boiler off at the fused spur switchWait 60 seconds and switch the power back on to see if the error clears
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