BoilerFaultCodesYour boiler's main control computer has developed an internal electrical fault and can no longer safely operate the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: There is an internal fault in the Automatic Control Module.
What causes this fault?
This fault occurs when the boiler's internal computer suffers a hardware failure, meaning it can no longer process data or send signals to other components safely. The most common reason is typical wear and tear on the electrical circuitry or a sudden power surge that has damaged the delicate components on the control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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