BoilerFaultCodesYour boiler's internal control boards are not communicating correctly because they do not recognise each other's software or settings.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Display and Main PCB incompatible
What causes this fault?
This fault occurs when the boiler's two internal computer brains—the main circuit board and the display board—lose their digital connection or fail to recognise each other. The most common reason is that one of the boards has been replaced with an incorrect version, or a sudden electrical surge has corrupted the software settings that link them together.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F70 — no call-out fees, no surprises.
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