First, check to see that the fan blades turn freely by hand and coast after being spun. If rotation is in any way stiff, this is a sign of dirty, dry, or gummed bearings, which can slow the motor. Sometimes the bearings can become tight and binding which can also be an issue.
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First, check to see that the fan blades turn freely by hand and coast after being spun. If rotation is in any way stiff, this is a sign of dirty, dry, or gummed bearings, which can slow the motor. Sometimes the bearings can become tight and binding which can also be an issue. You can possibly oil this.
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Second, does the fan wobble at all? If for any reason the blade pitch is steeper on one or more blades than the motor is designed for, this will slow the motor. This can often be the cause of warping, or a blade being knocked off balance. This will also cause the fan to wobble or shake. See the section on balancing. You can bend the blades to a shallower pitch if they appear to be too steep, but be extremely careful as blade brackets can break easily.
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Second, does the fan wobble at all? If for any reason the blade pitch is steeper on one or more blades than the motor is designed for, this will slow the motor. This can often be the cause of warping, or a blade being knocked off balance. This will also cause the fan to wobble or shake. You can bend the blades to a shallower pitch if they appear to be too steep, but be extremely careful as blade brackets can break easily.
Most fans made in recent years use permanent split capacitor motors, as they are efficient and reliable. However with age capacitors can drift in value. If the blades turn freely and are balanced, the cause of a fan running slowly is almost always a bad capacitor. The capacitor is a small black box or silver cannister with two or more wires attached, and is located inside the switch housing, motor housing, or inside a bell on top of the motor. It should be replaced with a capacitor of equal value, they are marked i.e. 6uf, 4uf, etc. Some fans have capacitors with two or more values, they should be replaced with the equivalent of those values by one or more capacitors
First, check to see that the fan blades turn freely by hand and coast after being spun. If rotation is in any way stiff, this is a sign of dirty, dry, or gummed bearings, which can slow the motor. Sometimes the bearings can become tight and binding which can also be an issue.
Second, does the fan wobble at all? If for any reason the blade pitch is steeper on one or more blades than the motor is designed for, this will slow the motor. This can often be the cause of warping, or a blade being knocked off balance. This will also cause the fan to wobble or shake. See the section on balancing. You can bend the blades to a shallower pitch if they appear to be too steep, but be extremely careful as blade brackets can break easily.
Most fans made in recent years use permanent split capacitor motors, as they are efficient and reliable. However with age capacitors can drift in value. If the blades turn freely and are balanced, the cause of a fan running slowly is almost always a bad capacitor. The capacitor is a small black box or silver cannister with two or more wires attached, and is located inside the switch housing, motor housing, or inside a bell on top of the motor. It should be replaced with a capacitor of equal value, they are marked i.e. 6uf, 4uf, etc. Some fans have capacitors with two or more values, they should be replaced with the equivalent of those values by one or more capacitors