Your boiler has stopped working because the internal fan, which clears away waste gases, is unable to spin or start up.
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.
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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A boiler cover plan would cover faults like 129 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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