BoilerFaultCodesYour boiler's internal computer has lost contact with its control panel or external sensors, meaning it cannot receive the instructions it needs to work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Break in communication
What causes this fault?
This fault occurs when the boiler's main control board can no longer 'talk' to the display screen or external controls. The most common reason is a loose connection in the internal wiring, though it can also be caused by moisture damage or a component failure on one of the electronic circuit boards.
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 A8 — no call-out fees, no surprises.
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