BoilerFaultCodesYour boiler's main control unit has lost communication with one of its electronic plug-in modules, meaning the system cannot talk to itself correctly.
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 central brain fails to recognize one of the electronic expansion cards plugged into its circuitry. The most common reason is a communication failure caused by a loose internal connection, a power surge that has glitched the memory, or a physical component failure on the control board itself.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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