BoilerFaultCodesYour boiler's internal computer has encountered a software or communication error and cannot operate properly.
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 main control board experiences a critical internal communication failure or a software glitch. It is usually caused by a component failure within the circuitry or an electrical surge that has corrupted the board's ability to process data. In some cases, loose or damaged wiring connections between the internal modules can also trigger this shutdown.
DIY fix possible
Locate the reset button on the front control panel.Press and hold the reset button for several seconds.Wait for the boiler to restart and monitor if the code clears.
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