F12 High
Your boiler's internal computer has lost communication with the control panel or display, preventing the system from operating.
Technical description: Main board connection fault
Typical repair cost: £180-450 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Protect yourself from future repair bills
A boiler cover plan would cover faults like F12 — no call-out fees, no surprises.
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Parts commonly replaced
- Main Printed Circuit Board (PCB)
- Display Interface Board
- Wiring Harness
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