BoilerFaultCodesTechnical description
Internal control unit error
What causes this fault?
This fault occurs when the boiler's internal circuit board suffers a critical hardware failure or loses the ability to talk to other electronic components. It is often caused by an electrical surge, moisture ingress, or simply the natural degradation of the solder joints and microchips over time. Because the brain of the boiler can no longer guarantee safe operation, it shuts down the system entirely.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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