BoilerFaultCodesTechnical description
Internal control box failure: check/replace the control box.
What causes this fault?
This fault occurs when the boiler's internal computer brain suffers a fundamental hardware failure or a memory corruption. It is usually caused by electrical components wearing out over time or damage from a sudden power surge. Once this part fails, the boiler can no longer monitor safety sensors or control the flame, so it shuts down entirely for safety.
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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