BoilerFaultCodesYour boiler's internal computer has encountered a critical electronic error and can no longer communicate with the rest of 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: internal failure - electronic
What causes this fault?
This fault occurs when the boiler's main control board suffers an internal hardware failure, essentially acting like a crashed computer that can no longer process instructions. The most common reason is electrical degradation of the board's components or a communication break in the internal wiring that prevents the system from running safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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