BoilerFaultCodesTechnical description
Internal error – possible control board problem
What causes this fault?
This fault occurs when the boiler's main control board suffers an internal electronic failure or loses the ability to communicate with its own memory chip. It is usually caused by aged circuitry or a sudden electrical surge that has damaged the delicate components inside the control box. Because the boiler's 'brain' can no longer verify that it is operating safely, it shuts down the system entirely to prevent any hazard.
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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