BoilerFaultCodesTechnical description
Internal control unit error
What causes this fault?
This fault occurs when the boiler's main control board suffers a critical internal communication failure or a hardware malfunction. It basically means the 'brain' of the boiler can no longer process data or send instructions to vital components like the gas valve or fan. The most common reason is the natural degradation of electrical components on the circuit board or loose connections within the internal wiring harness.
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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