BoilerFaultCodesYour boiler’s internal computer has encountered a critical electronic error and can no longer communicate with the main 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 central brain suffers a critical hardware failure, preventing it from processing information or sending commands to other components. It is often caused by an electrical surge, moisture ingress onto the circuitry, or general component degradation over time. Because the internal communication has broken down, the system shuts down entirely to ensure safety.
This fault is slightly more common during winter or storm season, as increased electrical grid activity and power surges can damage sensitive electronic components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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