Ceiling Fans

A Few Tips


I'm not any sort of authority on ceiling fans, but I am a Mechanical Engineer and I have owned no fewer than seven ceiling fans for 25+ years.  My fans are cheap -- I'm a skinflint -- so I've got some experience in what to avoid in cheap fans.

In my experience, there are three common problems that befall cheap fans:  The bearings get noisy, the capacitor fails, or the blades deteriorate.

Bearings:

Most ceiling fans have ball bearings.  In most applications, this would be a good thing; ball bearings are precision manufactured, durable, and thanks to mass production and standardization are relatively inexpensive and readily available.  In this case, however, ball bearings are arguably the worst option.  A ball bearing consists of steel balls rolling around steel races, and the metal-to-metal rolling generates a metallic sound.  New, these bearings are pre-lubed with some sort of relatively thick grease that not only lubricates the rollers but also dampens any noise they generate.  After a while, though, this grease dries out a bit and gets pushed out of the races and the fan develops a sound when running.  It's not really a fault; it'll run for many years making that noise.  But if you're trying to sleep in that room, that ssssssssss sound over your head might disturb your slumber.

You can try lubricating the bearings, but your odds of success are poor.  The bearings are sealed, which means they have little metal covers with rubber edges over each side to keep dust and dirt out.  It also keeps oil out.  You might be able to use a hypodermic needle to inject a bit of light lubricating oil past the rubber edge of the seal, but unfortunately light oil will only make the noise worse!  It'll rinse the rest of the thick grease out of the bearings, and they'll be really noisy from then on.  What it really needs is something akin to wheel bearing grease to dampen the sound, but you'll never get that stuff in with a hypodermic.  If you're really good, you might be able to pry out a clip, lift the dust seal up, spoon some grease in there, and reinstall the seal and clip.  Good luck!

One other possibility involves motorcycle chain lube.  This stuff comes in a spray can with a tube on the nozzle.  When sprayed, it comes out of the tube as a very thin, watery fluid, perfect for soaking into the links of a motorcycle chain.  Once out of the spray can, though, a solvent quickly evaporates, leaving a rather thick grease behind.  If you could get that stuff into the bearings, it might work.  I've never succeeded.  And remember, you're dealing with lubricants and solvents in close proximity to an electrical device.  Spilling it all over everywhere is not good, especially if you're dumb enough to turn the fan on before it dries.

The obvious answer to all this is to get the bearings out, which would give you an opportunity to clean and lubricate them properly "on the bench", or even to just throw them away and install new bearings.  Again, good luck!  Standardized ball bearings are designed to be replaceable, but these ceiling fans are not designed to be rebuilt in this manner.  You will find it very difficult to get the motor open, the old bearings out (requires a puller of some sort), back in, and back together.  While there are only four wires into a ceiling fan (ground, neutral, power, and lamp), inside the motor there are zillions of wires associated with the three speeds, and you'll probably mess up a bunch of them attempting that rebuild.

Back in the day, Hunter fans were built without ball bearings.  Hunter fan motors -- besides filling the entire cast metal housing, rather than most of a stamped tin casing being an empty shell surrounding a little motor -- had only one bearing, and it was a sleeve bearing immersed in an oil bath.  On paper this sounds cheap, there's no balls and no machined races, but in fact it's a vastly better way to build a fan.  It does require rather precision machining, and unfortunately that has to be done at the fan factory, they cannot just buy over-the-counter bearings and slap them in.  It also involves a little port on top where the owner has to check the oil level once a year and make sure it doesn't run dry.  For all that, you'll get a fan that'll run silently for 100 years.  Unfortunately, I think Hunter may have moved away from this design.  If you can find one that still has that design, I suggest you buy it.

Capacitor:

The capacitor on a 3-speed fan is actually two capacitors in one; in fact, it's possible to replace it with two separate capacitors, and some fans once came with two capacitors.  I suspect they fail in a variety of ways, but I had one fail dramatically:  The fan started making a humming sound, the blades ground to a stop, it began to smoke and stink, and molten goo started dripping from the switch housing on the bottom.  Fortunately, we weren't sleeping under it!  We got the power turned off quickly.

It may be dramatic, but believe it or not this is an easy fix.  Three screws remove the cover on the bottom of the switch housing, and the capacitor is inside.  Before you do anything, make very careful notes which wires connect to which.  New fan capacitors are readily available.  Oddly, the replacement capacitor may not have exactly the same specs as the original.  Don't worry about that!  The only difference it'll make is that the fan may run slightly faster or slower on the various speeds.  The new capacitor may have different color wires than the old one, and when you first hook it up something odd may happen like the 2nd speed is slower than the 3rd.  You'll get it working, though.

While in there, I recommend you fasten that capacitor down.  When left to rattle around in there, sometimes they will buzz or rattle while the fan is running.  A bit of double-sided foam poster tape usually works well enough; just apply it to the end of the capacitor and stick it down to the flat area deep inside the housing.  Obviously, if you have a fan that's running fine but has a buzz, you might want to look into this.

Blades:

There's nothing cheaper about a cheap fan than the blades.  These things are made of whatever particleboard or cardboard the maker thinks they can get away with selling.  Sure, they look nice when new, but they may not look nice for long -- especially if the fan is installed in an area where the humidity may get high, like in a garage or on a porch.  I live in Florida and I've had two fans with blades that drooped to nearly vertical at the tips within two months of installation.  I've also had fans with blades that delaminated, the pretty wood-pattern surface peeled right off and bubbled up along the edges.  Garbage.

The prevention for this is to buy "indoor/outdoor" fans.  These aren't really intended to get rained on, but they do come with blades that won't droop or delaminate in the humidity.  Rather than being made of veneered particleboard, they are typically made of either plastic or fiberglass.  Fiberglass would last until the sun burns out in this application; I dunno how long the plastic will last (I'll probably find out!) but it's certainly a lot longer than the particleboard.  Fans with these blades do cost a bit more, obviously, but in my opinion it's money well spent -- even if the fan is to be installed indoors.

You might not care for the appearance of the plastic or fiberglass blades, but if it'd help you can pick up a rattlecan of spray paint and paint them to match your decor prior to assembling your fan.  Lay out some newspaper and then lay out the blades using something to hold them above the paper.  I found that a socket set out of my toolbox worked great, using three or four sockets to hold up each blade.  Use Krylon Fusion or some other paint that's intended for plastic; some paints just won't stick to plastic.  Apply a thin coat, let dry, apply another thin coat, let dry, flip the blades over and repeat.  Try to apply the same amount of paint to each blade to help maintain balance.

If you've already got a fan with deteriorating blades, the fix would seem easy enough yet it is fraught with complications.  You can buy a set of Harbor Breeze replacement blades at Lowe's, and guess what?  The replacement blades are the indoor/outdoor type!  I guess they figure you've already learned your lesson and won't be interested in buying any more garbage blades.

The package says "fits most ceiling fans" -- but it lies!  Each blade attaches to a blade arm with three screws, and obviously that pattern of three holes has to line up or the blades won't fit.  And a cursory look at the fans on display in the same store reveals that the replacement blades won't fit most of them.  Many new fans now come with some sort of snap-on attachment scheme to save contractors the man-hours of having to install all those screws, and that attachment scheme uses a different hole pattern.

You could, of course, try to drill holes in your new blades to match the holes in your old blades.  If you're really good at machine work and have a drill press, this might work well enough.  For most of us, though, you'll have trouble getting the hole pattern exactly the same on the entire set of blades, and that may result in some blades being positioned a bit differently than others.  That, in turn, will result in balance problems.  You might be able to balance it out anyway (I'll discuss balancing fans below) but in general I don't recommend going that route.

A better idea is to replace the blade arms as well.  Right next to the packages of new blades you'll find packages of new blade arms, and the replacement blades will fit the replacement blade arms.  But then you face the next complication:  Will the new blade arms fit your fan?  Fortunately, your odds are a lot better here.  Each blade arm attaches to the motor with two screws, and if the spacing between the two screws is about 2-1/16", the replacement blade arms will fit.  If the spacing between the two screws is different, you're dead in the water, you'll probably need to buy a new fan.  When you select a new fan, besides checking for indoor/outdoor rating, you might want to check the attachment schemes to see if the replacement parts will fit!

Your next problem, of course, is whether the replacement blade arms are the right color.  Back to the spray paint again.

The cost of the set of replacement blades plus the cost of the set of replacement blade arms adds up to close to the cost of a new fan!  But don't be tempted to just buy a new fan.  The new fans in that price range have the crummy blades.  If your old fan is in good working order other than the blades, you'd be much better off buying the replacement blades and blade arms.  Besides, it'll save you the effort of removing the old fan and installing the new; you can just swap the blades out with it hanging there.

In my experience, the indoor/outdoor blades are considerably more massive than the particleboard blades.  Hence, when you turn the fan on it'll take longer to get up to speed, and when you turn it off it'll coast longer.

One other bit of good news:  I have found that, after installing the replacement plastic blades with new blade arms, often the fan doesn't need balancing.  At all.  Apparently the quality control on the indoor/outdoor blades is considerably better than on the garbage particleboard blades.  Duh!

Balancing:

If your fan wobbles when running, it needs balancing.  I'll provide some tips on successfully balancing a ceiling fan.  It's not difficult, but it does take some time -- which is the reason your contractor didn't do it.

The first step is to make sure all the blades are properly installed and straight.  Check all the screws holding the blade arms to the motor to make sure they're tight.  Ideally, loosen each pair and then pull outward gently on the blade while retightening it.  This ensures the clearance in the screw holes is taken up the same way on each blade.

Spin the fan slowly by hand and stand back and watch the blades so that, on one side of the fan, you're looking at the edge of the blade so it looks very thin to you.  With the fan turning slowly, each blade passing that same spot should appear exactly the same.  If one of them looks different, that means its pitch is different, the blade is twisted to a different angle.  You've got to fix that by fitting an adjustable wrench around the blade arm right where it attaches to the blade and gently twisting the arm.  Be very careful; those blade arms are cheap pot metal, and bending them too much will just snap them.  You can fix the mismatch between blades by moving some of the blades to a steeper angle to match the others, or by moving the others to the shallower angle of the first.  Doesn't matter as long as they're all the same.  It won't make any difference in how much air the fan moves, because moving all the blades to the shallower angle just permits it to spin a little faster at the same power setting.

If there's a ceiling right above the fan, pick a spot on it and measure the distance from the ceiling down to a blade tip.  Turn the fan around, trying not to rock it on its swivelling mount, and measure the distance to each blade tip from the same spot on the ceiling.  If any blade is lower or higher than the others, bend the blade arms accordingly to level them all up.  Warning:  This is likely to be rather difficult to do, because the fan motor won't sit still while you're trying to bend the blade arm.

Measure the distance from the tip of one blade to the tip of the next blade.  Measure the distance between all the blades in the same manner.  The tips should all be the same distance apart.  If the distance between one pair is a bit less than most and the distance between the next pair is a bit more than most, the blade in the middle is bent to one side.  You will need to bend that blade arm a bit sideways to put the tip back to centered between the blades to either side.  If the distances are all different, add up all the distances and divide by the number of blades to determine what the distance should be between each and every pair of blades.  If any blade has more than this on one side and less on the other, bend that blade first.  Keep bending blade arms until the blades are all equally spaced.

Now you'll probably need to go back and repeat all of those last three paragraphs, because fixing one thing tends to mess up another.  Keep at it until your blades are all equally spaced, level, and have the same pitch.  It won't serve any purpose to be balancing the fan until the blades are straight.

Balancing a ceiling fan is a remarkably unscientific process; rather than using a fancy computerized balance machine as is used on car tires, for balancing a ceiling fan we use trial-and-error.  Fans come with a balancing kit, but you really don't need one; I'll describe how to do the job with or without the kit.

Imbalance in a rotating assembly is a vector, meaning it's a particular mass applied in a particular direction.  To correct that imbalance, you will almost always need to be adding two weights to the blades of your fan.  The odds of your imbalance lining up perfectly with one blade -- allowing you to correct it with a single weight -- are minimal.  Far more likely, the imbalance will line up between two blades, so you'll need to apply a weight to each of two adjacent weights to properly balance your fan.

A given imbalance can be corrected with a small weight out at the tip or a larger weight closer in.  The weight multiplied by the distance from the center is what's important.  The balancing kits take advantage of this fact by giving you only one size weight to work with; you achieve balance by how far out from the center you apply them.  They also provide a clip that weighs the same as the balance weight, so you can slide the clip around until the fan balances and then stick a weight down where the clip is.  They only give you one clip, so you've got to apply one weight and then start over to apply the second.  Since the fan won't be perfectly balanced with the first weight, your trial-and-error involves trying to figure out which spot results in the least wobble, which is more difficult to discern than no wobble at all.

You can forget the clip and balance the fan by just taping the weights down with Scotch tape and peeling them up and moving them around.  Since you're using the weights themselves rather than a clip, the weights can be heavier or lighter than the weights that come with the balance kit.  You can use a paper clip, a small bit of scrap metal, whatever.  Once you've decided where they need to go, remove the Scotch tape and fasten them down permanently.  I often balance fans using very thin, broad pieces of sheet metal applied with clear packing tape, since that makes the flattest application to the blade.

Balancing a fan is trial-and-error, which requires patience.  Run the fan at high speed, notice how much it wobbles.  Stop it, stick a weight on it near the inner end of a blade, then run it again and see if the wobble is better or worse.  If worse, try a blade on the other side of the fan.  If it doesn't seem much different, try an adjacent blade.  If better, try moving the weight a bit outward on the same blade.  Keep stepping outward until the wobble reaches a minimum and then starts getting worse again.  The spot where the wobble is minimum is where you want that weight to stay.  If you reach the end of the blade and the wobble is still improving, your weight is too light, you either need to use a bigger weight or two weights on that blade.

The second weight should go on an adjacent blade.  There are two adjacent blades; try one and then the other, again starting with the weight near the inner end.  If one of the farther blades works better, you put the first weight on the wrong blade.  If adding weight to the opposite blade on a 4-blade fan is what works best, you really screwed up that first weight.  If you did things correctly, this second blade will require less weight than the first, so you might opt to use a lighter weight than the first one.  Using the balancing kit, of course, you'd just use the same size weight mounted closer to the inner end.

If you've done the job correctly, the fan should have no wobble.  None at all.  It takes a lot of patience to get it that good, though, so most people quit when it's "good enough."  Hey, if it's good enough for you, it's good enough.  It's probably a bunch better than it was when you started.