BoilerFaultCodesYour boiler's main internal screen is having trouble communicating with the central control board, meaning the boiler cannot receive commands to turn on.
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 data link between the boiler's control panel and the main internal brain is broken or interrupted. The most common reason is a loose or damaged ribbon cable, but it can also be caused by an electrical component failure on one of the circuit boards. Without this connection, the boiler cannot process your heating requests and shuts down for safety.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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