BoilerFaultCodesYour boiler's internal computer has developed a fault and can no longer communicate with the rest of the system safely.
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 main control board experiences an internal electronic failure or a breakdown in its memory processing. It is usually caused by aging electrical components on the circuit board that have finally worn out or been damaged by a sudden power surge. Because the 'brain' of the boiler can no longer verify that it is operating safely, it shut downs the system entirely to prevent any hazards.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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