BoilerFaultCodesYour boiler's internal computer has lost communication with the control panel or display, preventing the system from operating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main board connection fault
What causes this fault?
This fault occurs when the boiler's main brain and the front display panel stop talking to each other due to an electrical communication break. The most common reasons are a loose internal plug, moisture getting onto the electronics, or a component failure on one of the circuit boards themselves.
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 F12 — 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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