BoilerFaultCodesYour boiler has detected an internal communication error between its electronic control boards or a software fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: ALTERNATING 'L' '8' GO TO FRAME 89
What causes this fault?
This fault occurs when the main control board and the display panel stop talking to each other effectively. It is usually caused by a loose wiring connection between the two components or a critical failure of the internal software on the main circuit board. Without this constant stream of data, the boiler shuts down as a safety precaution because it can no longer monitor its own operations.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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