BoilerFaultCodes.com
F008 High Lockout

Your boiler has stopped working because the fan that clears exhaust gases from the unit is not spinning at the correct speed.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Incorrect fan speed

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is not spinning at the required speed to safely clear exhaust gases. The most common reasons are a mechanical failure within the fan motor itself or a communication issue where the control board can no longer send signals to the fan. In some cases, loose or damaged internal wiring can also prevent the fan from receiving the power it needs to start.

Typical repair cost £180-450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Protect yourself from future repair bills

A boiler cover plan would cover faults like F008 — no call-out fees, no surprises.

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