BoilerFaultCodesYour boiler's internal computer brain has encountered a glitch and needs to be restarted.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal electronic fault - Turn the power off and on again. If the fault persists, it may be the boiler control board.
What causes this fault?
This fault occurs when the boiler's main control board suffers a communication error or an internal electronic failure, preventing it from managing the heating process safely. It is often caused by a sudden power surge or simple component wear that disrupts the 'brain' of the appliance. If a power reset doesn't work, it usually means the electronic circuitry has failed permanently and can no longer process commands.
DIY fix possible
Locate the power switch or fused spur for the boiler.Turn the power off for 30 seconds.Turn the power back on and see if the 'L' code clears.
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