BoilerFaultCodes.com
129 High Lockout

Your boiler has stopped working because the internal fan, which clears away waste gases, is unable to spin or start up.

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 doesn’t start

What causes this fault?

This fault occurs when the boiler's control system attempts to start the fan but receives no confirmation that it is actually spinning. The most common reasons are a build-up of debris blocking the fan blades, a complete motor failure, or a fault in the electronic board that sends 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.

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Protect yourself from future repair bills

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