BoilerFaultCodesTechnical description
Internal control box failure: check/replace the control box.
What causes this fault?
This fault occurs when the boiler's internal electronic brain can no longer process data or send signals to individual components safely. The most common reason is the natural degradation of electrical circuits or a sudden power surge that has damaged the delicate components on the main control board.
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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