Stopping Ceiling Fan Wobble
For a variety of reasons your ceiling fan many wobble. The following procedures have been developed over a period of years and are designed to reduce the problem of fan wobble.
Step 1 – Visual Inspection
a. Make certain all blades are firmly attached. Screws can loosen over time
b. Check that all blades are straight and true. Blades can warp over time and this can cause an eccentricity in the way they move air. This eccentricity can then create a wobble in your fan.To check if blades are warped or bent, first look along each blade for a twist in the blade or an increase in the angle of the blade along its length. Second, a measurement from the ceiling to the blade tip can be made. Leave the measurement tool in the same place and rotate each blade around to the point of measurement. This should give you an indication if you need to replace the blades. Blades that are not straight and true need to be replaced to correct the fan’s wobble.
Note: Blades are weighed and then packaged with partners of equivalent weight and thus need to be replaced as a complete set. Using one or more dissimilar blades may unbalance the rotational inertia of the unit causing more wobble.
c. Turn your fan on and check for wobble. If the above process has not eliminated the wobble problem, you need to dynamically balance your fan.
Step 2 – Dynamic Balancing
Dynamic balancing involves counter-weighting to neutralise any eccentricities in the rotational inertia. By using a small weight opposite to the point or wobble, you can in almost all cases eliminate the wobble. The procedure requires a bit of trial and error and a certain amount of patience to achieve a perfect result.
a. Determine which fan speed causes the most wobble. This will almost always be the highest speed.
b. Turn off the fan. If you have a blade balance kit attach the balance clip half way between the blade tip and body of the fan on the rear edge of the blade. If you don’t have a balance kit firmly attach an Australian 10 cent piece to the middle centre of the blade, ensuring that it won’t detach during testing.
Caution: Be careful to say clear of the blades when running. If the clip or counter weight is not secure, injury may result from it dislodging and striking items or people in the vicinity.
c. Turn on the fan. Observe if the wobble is better or worse. Turn off the fan and move the clip to the next blade. Perform this task on all blades and note which blade the clip or weight improves the wobble the most.
d. Place the clip back on the blade which showed the most improvement and by trial and error move the clip in and out along the blade to find the position which most improves the wobble. You will need to stop and start the fan each time to move the counterweight.
e. Once the exact position is determined, you will need to place a permanent counterweight on top of the blade on its centreline directly in line with the balance clip or trial counterweight. Remove the temporary counterweight and enjoy a wobble free fan.
