Stand Fan And Floor Fan Cannot Start Turning - Page 1
Forum section: electronics / beginners

author: Boris_yo
author_rank: Frequent Contributor
timestamp: July 18, 2013, 05:39:01 pm
content: These fans are old I would say and as time passed, they started to refuse to start at low speed levels. There are in total3 speed levelson each and as more time passes, fans require higher speed levels to start turning. Recently both fans start only on final 3rd speed level and one of fans, starts barely turning and it takes less than minute to start turning normally. I can however reduce speed level to 2 on one of them and it keeps spinning at lower speed but should I set it on 1st speed level, it soon stops turning. You can hear z-z-z-z-z sound as fan struggles to start turning.I am wondering why this is happening fans. Do fans have starter or their motor gets weaker after a while? Is there something I can fix or it is time for me to get new fans?Finally, when buying new fan does it matter with how many paddles in order to ensure fans durability? I fans with 3 and 5 paddles.

author: SeanB
author_rank: Super Contributor
timestamp: July 18, 2013, 06:05:05 pm
content: You need a new 2.2uF 275v capacitor in the fan, it has gone low in value, and as well the grease in the bushings has gone hard, and needs to be relubed with regular engine oil. Some have a split capacitor with 3 leads, one section is 0.5uF, the other is 1.5uF. Easy to tell as it has 3 leadout wires.As to blade number, it makes no difference, the motors inside are likely the same cheap motors made by assorted small vendors using the same patterns, they are all cheap and nasty.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: July 18, 2013, 06:22:42 pm
content: Must I give fan's current capacitor time to discharge in order to not get electrocuted? Is this task of replacing capacitor feasible for DIY'er in home repair like me?

author: SeanB
author_rank: Super Contributor
timestamp: July 18, 2013, 06:30:06 pm
content: Discharges in under a second, and is easy to replace, it is a black rectangular device at the rear, either with a single screw holding it down or just taped in place.

author: IanB
author_rank: Super Contributor
timestamp: July 18, 2013, 07:18:21 pm
content: Before you look at electrical issues, make sure the fan blades spin freely without any resistance. If the bearings are gummed up then no electrical cure will help.

author: bilko
author_rank: Frequent Contributor
timestamp: July 18, 2013, 08:45:29 pm
content: It definitely sounds like the bearings need cleaning and oiling. A couple of drops of sewing machine oil works well.

author: Smokey
author_rank: Super Contributor
timestamp: July 18, 2013, 08:58:43 pm
content: Fans are dust magnets. That dust gets into the oil/grease and makes dust paste which has huge friction. Clean up the mechanical bits and it should run fine. Just don't forget to replace the oil/grease.

author: SeanB
author_rank: Super Contributor
timestamp: July 19, 2013, 06:21:46 pm
content: The grease used is poor quality ( I think they make it out of old cooking oil that is rancid, just boiled and mixed with clay) and goes hard and polymerises with time, but as well the capacitors are not good and slowly go low in capacitance, compounding the problems.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: July 19, 2013, 08:29:17 pm
content: You know this because you reverse-engineered fans?

author: bilko
author_rank: Frequent Contributor
timestamp: July 19, 2013, 09:10:40 pm
content: Its called servicing and maintenance

author: SeanB
author_rank: Super Contributor
timestamp: July 20, 2013, 04:59:42 am
content: It's called being an electrician and having a lot of fans around in a hot country. I do white goods at work, but do not do it private or for free. I meet these slow fans a lot, though often they are so poorly put together it is easier to buy a new one as the plastic parts will have gone so brittle that they shatter when touched.

author: G7PSK
author_rank: Super Contributor
timestamp: July 20, 2013, 03:35:25 pm
content: Most of these fans run in oilite bushes (http://en.wikipedia.org/wiki/Oilite) they dry up after a while and the bearing becomes tight, its best to replace them but often not worth the cost of doing so. You can in such cases just mix some oil an benzine, about 80% oil in the mix and wash the bearings in petrol or benzine and then soak in the mixture over night, works in most cases sometimes after doing so the bearing will rattle because although the motor stops due to sticky bearings the bush has actually worn. If the bearing are small ball races these are very often sealed and the only sensible thing is to replace them any good bearing supplier should stock them, if there is no number written on the inner race just take the inside shaft dia. and the outer dia. and the width and you should be able to find a match, most bearings are an off the shelf item very few are made a special size.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: August 13, 2013, 06:47:33 pm
content: @SeanBAttached is the picture of motor after I took off plastic covering of my 12 year old fan. You mentioned capacitor but there isn't any that I could find.

author: M. András
author_rank: Super Contributor
timestamp: August 13, 2013, 06:53:36 pm
content: lol its the black screwed rectangular thing

author: SeanB
author_rank: Super Contributor
timestamp: August 13, 2013, 07:41:25 pm
content: Standard 1u5 unit, common on these units. Clip the black and white leads to it close to it and replace it. It probably will measure well under 1uF if you measure capacitance. The motor normally stops turning at about the 500n mark.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: August 14, 2013, 10:06:52 am
content: How do I measure capacitance? All I have is multimeter.

author: IanB
author_rank: Super Contributor
timestamp: August 14, 2013, 01:23:32 pm
content: You don't. You simply obtain a replacement capacitor of the same specifications and fit it. Assuming the motor has no other problems like stuck bearings or burned out coils it will now work.

author: Shock
author_rank: Super Contributor
timestamp: August 14, 2013, 01:51:30 pm
content: Fixing the mechanical problem first does save timeQuote from: Boris_yo on August 14, 2013, 10:06:52 amhttp://bit.ly/16PwAIKCap will cost you around $5 plus shipping all the specs are right there on the capacitor.You should read up on how capacitors work, how to read their specs, and how to safely discharge them.I am concerned if your repairing things like this to use or sell, as lack of knowledge on appliance repair can easily kill someone.

author: MrAureliusR
author_rank: Unknown
timestamp: August 14, 2013, 02:26:37 pm
content: Quote from: Shock on August 14, 2013, 01:51:30 pm+1 to this. It seems the OP isn't even reading the replies to this topic, someone specifically mentioned the cap was a 'black box with either a single screw or tape holding it down' and then posted a picture with that exact description stating he couldn't find the cap...

author: Boris_yo
author_rank: Frequent Contributor
timestamp: August 16, 2013, 01:18:53 am
content: I have found black rectangular capacitor although the problem now is that before I did anything, the fan stopped working. Initially it took it warm up time to start spinning and at that time I could barely hear motor working. Now however it does not work and nothing can be heard from it. Maybe bearings are stuck? In addition to bad capacitor this can be another problem.

author: Shock
author_rank: Super Contributor
timestamp: August 16, 2013, 04:23:27 am
content: Think to yourself... how could I test if the bearings are stuck?

author: G7PSK
author_rank: Super Contributor
timestamp: August 16, 2013, 07:44:05 am
content: I would say that the bearings were tight and now that you have persisted in running the fan despite all the information given, the windings have given up the ghost which is why you cant hear any sound from the fan motor.

author: dr_p
author_rank: Frequent Contributor
timestamp: August 16, 2013, 07:51:49 am
content: Ghost or no ghost, it's not dead until the magic smoke is released.

author: David_AVD
author_rank: Super Contributor
timestamp: August 16, 2013, 07:54:15 am
content: "If at first you don't succeed... run the bastard into the ground until it doesn't work at all !"

author: SeanB
author_rank: Super Contributor
timestamp: August 17, 2013, 06:11:00 am
content: Those motors are about the only thing into which the cheap ass manufacturers actually put a thermal fuse, typically a 112C unit. Buried in the windings inside, it is possible to replace it, but you will find it difficult to do. I keep a small packet of around a dozen for that. Typically though if the windings have gotten that hot that the fuse melts then they themselves will fail later.

author: David_AVD
author_rank: Super Contributor
timestamp: August 17, 2013, 06:26:52 am
content: I shudder to think about where people have found a thermal fuse open-circuit and simply bypassed it. One can only hope it's their own home they burn down.

author: SeanB
author_rank: Super Contributor
timestamp: August 17, 2013, 07:10:59 am
content: The thin wiring tends to act as a fuse in most cases anyway, it just blows.

author: Mechatrommer
author_rank: Super Contributor
timestamp: August 18, 2013, 04:01:37 am
content: Quote from: Boris_yo on August 16, 2013, 01:18:53 amas much as i want to help this tens of thousands km away guy, alas i think i'm doing nothing except wasting my time to teach someone who dont bother to figure out how a bearing works or how is it if it doesnt work. instead of making him fatter (teach or tour guide in forum), why he is not going out learn something from local tech personnel, send his unit to electrician for repair and have a peek on how the guy repair things or simply if he has a really tight ass, go to local hardware store and play/fool around with "men's toy" thats abundant around there and then walk away, i'm sure the sale guys will let him. not only he will get his unit fixed, but he also can learn alot and stay healthy by working out his muscles, mind and sweat, not reading forum while eating popcorn. i'll ask the same from my kids, not 100% spoonfeed.

author: MrAureliusR
author_rank: Unknown
timestamp: August 18, 2013, 10:01:05 am
content: Quote from: Mechatrommer on August 18, 2013, 04:01:37 amBecause we're the 1% of people who take it upon ourselves to figure out how things work. Most people just want someone to walk them through it or better yet fix it for me! Its not the 1930s where user service was the norm. Even into the 80s there was still a lot of it. I'm lucky my dad was a self taught electrician and could fix almost ANYTHING electronic. It used to amaze me as a kid that my smashed Sega could ever play another game after I laid a smackdown on it after losing over and over at some game. But he managed to fix it - every time! Totally inspired me and as I grew up I always tried to fix things myself. I usually failed but learned a lot.Its the Disposable Generation I'm in. Your phone stops working? Throw it out and buy a new one. Same for TVs, microwaves, DVD players, everything. Because replacing it is cheaper than sending it for repair.Sad state of affairs. At least EEs still get paid fairly well...Typed using Hacker's Keyboard for Android

author: SeanB
author_rank: Super Contributor
timestamp: August 18, 2013, 10:28:38 am
content: Plumbers get paid better, but the work is just up to the neck in what is eloquently described as "Honey". I do it as well, but often I will need to go and shower immediately after, and wash the clothes as well.

author: dr_p
author_rank: Frequent Contributor
timestamp: August 21, 2013, 01:58:55 pm
content: I'm on par withMechatrommer, in that I like to help people, when and if I can, but I feel insulted if one doesn't show the least bit of effort on his part, but demands solutions.Case in point, the OPmightconsider spinning the fan blade by hand to see if the bearing is stuck, instead of thinking out loud on the forum. GIIIZ

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 10, 2014, 11:59:18 am
content: Took off fan's net covering and tried spinning blade by hand and noticed heavy resistance unlike another working stand fan I have at home that works well.

author: digsys
author_rank: Unknown
timestamp: January 10, 2014, 12:21:52 pm
content: When my Industrial Aussie made Mistral did the same thing a couple yrs back, a friend of mine came by and, by coincidence,happened to have designed it. He said that they had taken short cuts in assembly, and there was no proper alignment doneof the shaft and the bearings, just press fitted together. He simply "whacked" the ends of the casting, 90o to the shaft,until it spun freely then, knowing where the bearing was, drilled a small hole to lubricate it. Finally used a small screw to plug the hole.It's worked ever since, better than new. He's done it twice since to my fans, always perfect results.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 10, 2014, 01:26:46 pm
content: Have disassembled motor compartment and lubricated bar and back bearing using what I had - penetrating and rust preventing oil. The bar that holds fan blades could spin better with way less resistance but after assembling back and plugging it to mains, nothing spinned anymore and no buzzing sound was heard at all. Maybe fan was already dead but if I tried plugging it in before disassembly, I could at least see if it shows any signs of being operational. Maybe after disassembly Imisplaced that square-like partwhich has copper wires around it? Maybe polarization plays important role here?Does it matter how how I align it exactly because I could align it with whatever side it could be aligned? I also lubricated this bearing on the back that had some grease in it by the way:There was also floor fan that does not show any signs of operation. It seems like this stand fan also started to show same signs either before or after I took care of it.