BoilerFaultCodesYour boiler's internal display screen is unable to communicate with its main control computer, preventing the boiler from firing up.
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 digital connection between the boiler's control panel and its internal computer is broken. It is usually caused by a loose wiring plug, moisture getting into the electronics, or a component failure on one of the circuit boards. Because these parts cannot 'talk' to each other, the boiler stays off for safety until the link is restored.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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