BoilerFaultCodesYour boiler has stopped working because the internal control panel cannot talk to the main computer brain of the unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No reception by the main board (MMI Lead)
What causes this fault?
This fault occurs when the communication link between the boiler's display interface and its main internal computer is broken. The most common reason is a loose or damaged data cable connecting the two components, though it can also be caused by an electrical failure within one of the circuit boards. Without this constant 'handshake' between the parts, the boiler cannot safely receive commands and will shut down.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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