BoilerFaultCodes.com
29 High Lockout

Your boiler has detected an issue with the fan, which means it cannot safely move air and gas through the system to start the heating process.

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: Fan defect.

What causes this fault?

This fault occurs when the boiler's control system loses communication with the fan or detects that it isn't spinning at the required speed. The most common reasons are a mechanical failure of the fan motor itself, loose internal wiring, or a fault on the main circuit board failing to send power to the unit.

Typical repair cost £250-£450 (including labour)

Engineer required

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

Find a Gas Safe engineer

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Protect yourself from future repair bills

A boiler cover plan would cover faults like 29 — no call-out fees, no surprises.

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