BoilerFaultCodesYour boiler's main control board has lost connection with the display screen, meaning the system cannot receive instructions and has stopped working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: User interface (display) communication error.
What causes this fault?
This fault occurs when the digital conversation between the boiler's internal computer and the front display screen is interrupted. It is usually caused by a loose wiring connection or a component failure on one of the circuit boards, preventing the boiler from receiving your temperature settings.
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 F12 — no call-out fees, no surprises.
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