Ceiling fan troubleshooting

Basic Troubleshooting

1. Fan is not working
2. Fan light is not working
3. Fan runs, but wobbles or shakes
4. Fan runs, but slowly
5. Fan makes mechanical noise while running i.e. clicking, knocking, grinding.
6. Fan makes a humming noise while running.
7. Fan makes an electrical buzzing noise while running.
8. Fan moves very little air.

I. Fan is not working

First, check to make sure that all controls on the fan are functional and set properly. The pullchain should be set to an operating speed (i.e. high), some fans have a speed knob or the like. If the fan has a reverse switch, be sure it it is seated fully in the 'up' or 'down' position. If the fan has a remote, make sure it has a good battery securely in place. If the fan has a more unique or unusual control system you may need to ask more specific questions (see our forums).

Does the fan have a light? Does the light work? If both the fan and the light are not working, it is likely a connection issue. Lower the fan canopy and/or housing, and check to see that all the wires are connected (see our wiring section for proper connections). Check to see that there is indeed power from the supply-- there could be a switch or breaker off, or a connection issue within the wiring. Lastly, open the switch housing to the fan and check that the white wire is connected to both the light kit and fan electronics.

If the light is working and the fan is not, the first thing to check is if the black wire has come disconnected inside the canopy. If it is connected, what is it connected to? Sometimes the fan motor is on a separate circuit that may not be energized. Check also in the switch housing to see that no wires are loose or disconnected.

Next, check to be sure that the blades turn freely. If they do not, the problem may involve stuck bearings (see 'oiling' section), a broken flywheel (see 'flywheel' section), or simply something stuck in the path of the motor or blades that does not belong there.

If the fan does not have a light, any of the above options are applicable. The red, blue, or black/white striped wire in the canopy and switch housing need not be connected as it is for an added light assembly.

II. Fan light is not working

If the fan is working but the light is not, the problem is usually a loose connection between the power source and the light kit. Make sure the red/blue/black & white striped wire is connected inside the canopy to the power source, and inside the switch housing to the light kit's black wire. The light kit's white wire should be connected to the white wire(s) inside the switch housing. Check also that the light kit's pullchain is functional. It is also possible that the fan's light is connected to a separate circuit from the fan motor, in which case the red/blue/black & white striped wire would be connected to a separate hot wire inside the fan canopy.

III. Fan runs, but wobbles or shakes

See section on balancing.

IV. Fan runs, but slowly.

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. See 'oiling'.

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 ceiling 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. More in the 'capacitor section'.

V. Fan makes mechanical noise while running i.e. clicking, knocking, grinding.

If it's a mechanical sound, chances are it is a mechanical problem. It could be something as simple as a wire that has slipped into the path of some moving parts.

First, does the fan wobble? If so, balance the fan (see the balancing section) and see if the noise persists. Often times a shaking fan will allow some loose part (such as a wire nut) to hit against a metal housing piece. Balancing the fan may silence the noise.

If the fan is balanced, the next thing to check is if anything is coming into the path of the blades or any other noticable moving part. Remove the blades. Run the fan motor. Does the noise persist? If not, the problem is something coming into contact with the blades.

Assuming the noise persists, open up the motor housing and rotate the motor slowly by hand. Observe where in it's path of rotation and at which point the noise occurs. Look also for any objects, such as a loose wire or wire nut, coming into contact with the rotor.

If the noise appears to be internal to the motor, it is most likely a bearing issue. Does the motor rotate smoothly? You may notice a catch in the movement as the noise occurs, or the noise may be fairly constant. Dry bearings can also make a grinding, squeeling, or rattling noise. See the section on 'oiling'.

Additional note: sometimes mechanical noises are the result of loose parts on the fan. Check the blades, blade brackets, light kit glass, etc, to be sure all the screws are tight.

VI. Fan makes a humming noise while running

In the case of noise complaints by fan owners, the vast majority encompass a humming noise when the fan motor is running. This is because all motors create vibration, and the humming sound you hear is that vibration being amplified by the fan housing, wood blades, even the structure the fan is mounted to. The key to a quiet fan is to isolate the motor vibration from all other parts. This occurs, in the majority of fans, in three places: between the motor and the blade brackets, between the blade brackets and the blades, and between the downrod/motor flange and the mounting bracket. Some fans also have vibration-isolating material between the mounting bracket and the ceiling.

On more expensive fans, a rubber flywheel is used to attach the blade brackets to the motor. This is extremely effective in dampening all vibration from the blades, and no additional isolating material is required on the blades. The downside is, especially in older designs, these rubber flywheels disintegrate and break with age. See the flywheel section for more information. On less expensive fans, rubber or paper spacers are used between the blade brackets and the motor.

Some fans, especially those that lack rubber flywheels, have rubber or paper washers between the blades and the blade brackets. This also helps dampen the transfer of vibration to the blades.

The most consistent place for vibration isolating material is attached to the mounting bracket. These days, most downrod fans mount with a ball-and-socket type bracket, and the ball, attached to the downrod, is usually made of rubber. Some industrial fans, as well as older fans, use a rubber grommit or grommits attached to a j-hook or other mounting bracket. On hugger-type fans there is usually a rubber washer or washers between the motor flange and the mounting bracket. Lastly, some fans have rubber spacers between the mounting bracket and the ceiling.

If your fan makes a noticable humming noise, inspect it for the above mentioned types of vibration-isolating material. With the exception of the rubber flywheel, if your fan is lacking any of the above, they are easy to add and should solve the majority of humming problems. You can always add additional material as rubber washers and spacers are readily available.

VII. Fan makes an electrical buzzing noise while running.

By far the most common cause of an electrical noise from a fan is the use of an improper speed control. Most fans made today, especially those with imported 16 pole motors (see 'quality/motor info' section) are not designed to be used with Solid State speed controls. Solid State speed controls induce noise on the AC line (spikes in the wave form) that are amplified by the motor windings. Use a speed control, such as a capacitor type, that is recommended for your fan. Do NOT use a dimmer switch EVER on a fan motor. See 'controls section' for more details.

Some older fans, particularly those made in America, ARE designed to be used with Solid State speed controls, and may even have one built in. However over time the insulation on the motor windings of these fans can break down, causing them to buzz. The only solution to this problem is to take apart the motor and varnish the windings (not an easy task for most) or replace the control with a quieter type (if the Solid State control is built into the fan, again, not an easy task for most).

VIII. Fan moves very little air.

First, check and see if any of the other problems listed above apply. Running too slow? Off balance? Check and make sure the fan isn't operating in reverse (for most fans, clockwise, see 'reversing section'). Another, less likely, option is that the blades became bent or warped without actually putting the fan out of balance. If they became pitched too steeply that would also slow the fan, see above. But if the blades became warped or bent to a shallower pitch, that would not decrease the motor speed but would decrease the airflow. Observe the fan from the side to see if the blades are still pitched noticably. If not, reference the balancing section for bending them back into place.

Lastly, you might just have a cheap fan that doesnt move a lot of air. Peruse this site, and buy a new one!

Copyright © 2005 Dan Neuman

For more questions related to ceiling fans, please see our general ceiling fan FAQ page.