BoilerFaultCodesYour boiler's main control board has lost communication with an internal plug-in module or sensor, meaning it cannot currently operate.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Module not detected.
What causes this fault?
This fault occurs when the boiler's main control board loses its connection to a specific internal electronic component or plug-in module. The most common reason is a loose wiring connection or a hardware failure within the circuit board that prevents the various parts of the boiler from talking to each other. Because the control board can no longer 'see' all its necessary components, it chooses to shut down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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