BoilerFaultCodesYour boiler's internal computer has lost its connection with the main control board, meaning the system cannot communicate correctly to heat your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication interrupted.
What causes this fault?
This fault occurs when the boiler's central brain loses its ability to talk to the other internal electronic components. It is usually caused by a loose connection in the internal wiring or a component failure on the main circuit board that prevents data from flowing through the system. Think of it like a loose HDMI cable on a TV; the power is on, but the picture cannot get through.
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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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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