BoilerFaultCodesYour boiler's main internal computer has developed a fault and is no longer able to control the heating process 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 internal electronic brain experiences a hardware failure or a memory error. It is usually caused by electrical wear over time or a power surge that damages the delicate components on the circuit board, preventing it from processing safety information. Because the computer can no longer guarantee the boiler is operating correctly, it shuts down the system entirely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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