Selling fan suddenly completely run stop

Since a fan is a relatively simple machine, you can narrow it down quickly with a few checks.

Before dismantling anything, ensure the motor is actually receiving electricity.

• The Wall Switch: Check if the wall switch or the pull-chain has been toggled to the "off" position.
• Circuit Breaker: Check your electrical panel. If the fan is on a circuit with other high-load appliances, it may have tripped the breaker.
• The Reverse Switch: Sometimes the small toggle switch on the side of the motor (used to change summer/winter direction) gets stuck in the middle. If it’s not fully clicked to one side, the circuit is broken and the fan won't move.

With the power off, try to spin the fan blades by hand.

• If they spin freely: The bearings are fine, and the issue is likely electrical (capacitor or motor).
• If they are stiff or won't move: The bearings are seized or there is a massive buildup of dust and debris inside the motor housing. You might be able to fix this with a drop of non-detergent motor oil (SAE 10 or 20), but often a seized motor requires replacement.

The capacitor is a small black box inside the fan housing that provides the "torque" needed to start the motor.

• Symptoms: If you hear a faint humming sound when the fan is turned on, but the blades don't move, the capacitor has likely failed.
• The Jump-start Test: Turn the fan on and give the blades a manual push. If the fan starts spinning on its own after the push, the capacitor is 100% the problem. They are cheap and easy to replace.

If you smell a "burnt" or acrid odor coming from the fan, or if you see dark scorch marks on the motor windings, the motor itself has likely shorted out. At this point, it is usually more cost-effective to replace the entire fan than to attempt a motor rewind.