BoilerFaultCodesYour boiler’s internal computer brains are struggling to talk to each other, meaning the system cannot run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main PCB / Display PCB fault
What causes this fault?
This fault occurs when the main control board and the display panel lose their ability to communicate with each other. It is usually caused by a physical failure of the electronic components or a loose connection in the internal wiring, preventing the boiler from confirming it is safe to ignite.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F64 — no call-out fees, no surprises.
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