F3 High
Your boiler has detected an issue with its fan, meaning it cannot safely circulate air or clear exhaust fumes and has shut down as a safety precaution.
Technical description: Fan fault
Typical repair cost: £250-£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 F3 — no call-out fees, no surprises.
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Parts commonly replaced
- Fan motor
- Main circuit board (PCB)
- Wiring harness
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