BoilerFaultCodesYour boiler's main control system is having trouble communicating with an internal plug-in component, meaning it doesn't know how to operate 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 main internal computer loses its connection with a specific plug-in module or component on the circuit board. The most common reason is a communication failure caused by a loose internal connection or a electronic fault within the control module itself, which prevents the boiler from receiving the necessary instructions to fire up.
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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A boiler cover plan would cover faults like AC — no call-out fees, no surprises.
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