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Author Topic: Why does my fan take so long to speed up ?  (Read 10973 times)

neilep

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Why does my fan take so long to speed up ?
« on: 26/04/2006 18:28:08 »


I have a fan…I luff it…but why does it now take forever to speed up ?

I reckon it takes a good fifteen minutes to reach full potential and then it just fans away quite happily..

When turned off and on again it reaches speed efficiently…so..is it a temperature of motor thing happening here ? along with wear and tear ?

I would consider it a job well done if you could blow me the answer.......a blow job well done !!! *snigger snigger*;)



Men are the same as women, just inside out !

JimBob

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Re: Why does my fan take so long to speed up ?
« Reply #1 on: 26/04/2006 20:42:03 »
The fan sounds old to me. There probably is some sort of bi-metalic part heating up and making full contact after it is fully heated.



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Hadrian

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Re: Why does my fan take so long to speed up ?
« Reply #2 on: 26/04/2006 20:59:10 »
could it be that there is something deposit on or touching the bearing that is causing friction but heats up?  

What you do speaks so loudly that I cannot hear what you say.

neilep

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Re: Why does my fan take so long to speed up ?
« Reply #3 on: 27/04/2006 00:16:25 »
Well Jim is right, the fan is old...well...to be precise it is a very well used fan...We use fans a lot and if we get more than a years use out of it we consider it a job well done. We use the fans every night and I assume it must be a wearing down of something as we see this all the time, or as you said Jim a bimetallic part heating up...


Hadrian, that sounds reasonable too....I think the answer is it's time to buy another fan..

.....actually, that reminds me...toasters use bimetallic components too don't they ?........Gosh...I know stuff...YAYYYY !!

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Hadrian

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Re: Why does my fan take so long to speed up ?
« Reply #4 on: 27/04/2006 09:20:18 »
You could start a used FAN CLUB  

What you do speaks so loudly that I cannot hear what you say.

neilep

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Re: Why does my fan take so long to speed up ?
« Reply #5 on: 27/04/2006 14:00:56 »
quote:
Originally posted by Hadrian

You could start a used FAN CLUB  

What you do speaks so loudly that I cannot hear what you say.




Oh Nooooooooooo !!! :D

*wishes he stayed away longer* ;)...*takes head and walks into wall head down*

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ROBERT

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Re: Why does my fan take so long to speed up ?
« Reply #6 on: 28/04/2006 15:00:36 »
quote:
Originally posted by neilep



I have a fan…I luff it…but why does it now take forever to speed up ?

I reckon it takes a good fifteen minutes to reach full potential and then it just fans away quite happily..

When turned off and on again it reaches speed efficiently…so..is it a temperature of motor thing happening here ? along with wear and tear ?

I would consider it a job well done if you could blow me the answer.......a blow job well done !!! *snigger snigger*;)

Men are the same as women, just inside out !



The "angular momentum" of the fan would cause a delay of seconds to reach full speed. If it truely takes 15 minutes to reach full speed then it is probably due to faulty electrical contacts with the rotating part of the motor called "brushes".
http://www.wci.wcsd.k12.ca.us/itech/solarcar/sites/motor_how.htm
 
Brushes are often made of little blocks (5x5x5mm) of carbon, the carbon dust from worn brushes can cause short-circuiting within the electric motor and cause it to misfire.
If your motor's speed is erratic (misfiring) then it is probably full of black carbon dust and a thorough clean would solve the problem if it can be dismantled safely.
« Last Edit: 28/04/2006 15:04:03 by ROBERT »

neilep

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Re: Why does my fan take so long to speed up ?
« Reply #7 on: 28/04/2006 15:05:26 »
Robert !!....THANK YOU.

This man is a fantastic source of information.

Men are the same as women, just inside out !

Karen W.

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Re: Why does my fan take so long to speed up ?
« Reply #8 on: 28/04/2006 15:32:37 »
I agree with robert, I have fans that are thirty years old and we just take them apart carefully noting where everything needs to go back, especially if you are not used to tinkering. Then thoroughly clean everything from the inside out, checking your greased areas and adding new if necessary. Sometimes those old bearings need replaced or new lube, be careful about the kind of grease you use. Make sure it is for bearings. Sometimes there is still grease but it is so old it becomes ineffective after having broken down.Sometimes causing sluggish startup untill the grease is actually been moved around abit itself. New grease is usually what Bob adds automatically, especially is the fan has been running for some time. Sometimes the fan can capture dirt and grime around the base where it attaches to the rod, causing it to be gummy and noiseier then usual. I am no mechanic, but I have seen my hubby work on ours many times. He tinkers alot with old things like this. Typewriters too. He says No.one reason moving parts slow, is sticky yucky dust and grime. A fan has moisture and dust passing through it constantly and can really build up. You should be able to do this your self. Just make sure you unplug the thing and take notes if you need to. Make a diagram.You do need to check electrical contacts and replace them if neccasry. You will need a soldering gun if any are broken off or loose. In some cases, you might need a whole new wire. make sure your connections are clean and you don't ground your wire out on something that of course will burn it out and can cause a fire. You should try it, it might be a good project for one of those sleepless nights!
« Last Edit: 15/05/2006 06:04:42 by Karen W. »

ROBERT

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Re: Why does my fan take so long to speed up ?
« Reply #9 on: 28/04/2006 15:58:37 »
Karen W is not swearing, Neilep:  :)
"sodering" (USA) = "soldering" (UK)


"(Of England and America) ‘Two nations separated by a common language.

Sometimes the inquirer asks, ‘Was it Wilde or Shaw?’ The answer appears to be: both. In The Canterville Ghost (1887), Wilde wrote: ‘We have really everything in common with America nowadays except, of course, language’.  However, the 1951 Treasury of Humorous Quotations (Esar & Bentley) quotes Shaw as saying: ‘England and America are two countries separated by the same language’, but without giving a source.  The quote had earlier been attributed to Shaw in Reader’s Digest (November 1942)".
http://www1.btwebworld.com/quote-unquote/p0000149.htm



« Last Edit: 28/04/2006 16:10:19 by ROBERT »

ROBERT

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Re: Why does my fan take so long to speed up ?
« Reply #10 on: 28/04/2006 16:06:18 »
Why is this site so sodering slow ? :)
« Last Edit: 28/04/2006 16:07:23 by ROBERT »

neilep

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Re: Why does my fan take so long to speed up ?
« Reply #11 on: 28/04/2006 17:33:02 »
quote:
Originally posted by Karen W.

I agree with robert, I have fans that are thirty years old and we just take them apart carefully noting where everything needs to go back, especially if you are not used to tinkering. Then thoroughly clean everything from the inside out, checking your greased areas and adding new if neccasary. Sometimes those old bearings need replaced or new lube, be careful about the kind of grease you use. Make sure it is for bearings. Sometimes there is still grease but it is so old it becomes ineffective after having broken down.Sometimes causing sluggish startup until the grease is actually been moved around abit itself. New grease is usually what Bob adds automatically, especially is the fan has been running for sometime. Sometime the fan can capture dirt and grime around the base where it attaches to the rod, causing it to be gummy and noiseier then usual. I am no mechanic, but I have seen my hubby work on ours many times. He tinkers alot with old things like this. Typewriters two. He says no.one reason moving parts slow is sticky yucky dust and grime. A fan has moisture and dust pasing through it constantly and can really build up. You should be able to do this your self. just make sure you unplug the thing and take notes if you need to. Make a diagram.You do need to check electrical contacts and replace them if neccasry. You will need a sodering gun if any are broken off or loose. In some cases, you might need a whole new wire. make sure your connections are clean and you don't ground your wire out on something that of corse will burn it out and can case a fire. You should try it it might be a good project for one of those sleepless nights!



Karen, that's marvellous.

Will it be alright if I leave it plugged in and turned on whilst sitting in a full bath whilst I conduct the maintenance with a burning hot soldering iron ? :D:D

..I have always had fun taking things apart..............that's as far as I get !:D.....

..I truly wish I could do general household maintenance like fixing a fan because I can imagine the satisfaction of repairing something like that as an adrenalin rush !!..well...maybe a little subtler than that !....

I can't believe your fan is 30 years old !!..the life expectancy of a fan in this house is about  a year, but boy do we get good use out of them...we have them on every single night without fail ....I just like the feel of the breeze as I fall asleep ! (HA !!..collapse into a comatose stupor more like)

Thanks Karen for your fan orientated insight....hugs&shmishes to you xxx


ROBERT, thanks again as always....regarding the speed of the site there are a few ghosts in the machine at the moment unfortunately...if you browse over to the error log thread you'll see what's been going on....oh..and hugs&shmishes to you too xxx (but I don't do tongues !..sorry to disappoint you ;))



Men are the same as women, just inside out !
« Last Edit: 28/04/2006 17:35:27 by neilep »

Karen W.

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Re: Why does my fan take so long to speed up ?
« Reply #12 on: 29/04/2006 02:17:22 »
Hey Robert, is there really a difference in the spelling? Or did I just mis-spell it myself? Jeesh, I am bad! I am supposed to be the teacher here! Where the heck is Me old trusty  Dictionary?.......Looking.......looking......aha! I humbly apologize for my error and indeed tis mine! Seems we of little brains spelled it wrong....graval graval graval....so sorry ! Soldering iron it is! Thanks friends!

ROBERT

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Re: Why does my fan take so long to speed up ?
« Reply #13 on: 05/05/2006 17:12:54 »
quote:
Originally posted by Karen W.

Hey Robert, is there really a difference in the spelling? Or did I just mis-spell it myself? Jeesh, I am bad! I am supposed to be the teacher here! Where the heck is Me old trusty  Dictionary?.......Looking.......looking......aha! I humbly apologize for my error and indeed tis mine! Seems we of little brains spelled it wrong....graval graval graval....so sorry ! Soldering iron it is! Thanks friends!



No apology necessary Karen, your spelling is correct in America:-
http://www.ameritool-inc.com/store/moreinfo.cfm?product_ID=165&CFID=1759176&CFTOKEN=8541

" Britain and America are two countries separated by the Atlantic Ocean. "- Eddie Izzard.
http://www.geocities.com/hystericalvibrator/izzardquotes.html


« Last Edit: 05/05/2006 17:21:43 by ROBERT »

confusious says

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Re: Why does my fan take so long to speed up ?
« Reply #14 on: 16/05/2013 10:34:58 »
The reason is the bearings are wearing out, and specifically the grease has hardened, so whilst it is in motion, the grease in the bearings warm up, and start to loosen (melt effect), thereby causing less drag and hey presto your fan goes faster.

SeanB

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Re: Why does my fan take so long to speed up ?
« Reply #15 on: 16/05/2013 18:51:17 »
If it is a ceiling fan then likely the fault is either grease in the bearings going hard ( bit hard to fix as they are pressed in and hard to remove, you can drip oil down the shaft to the top one but it is messy, or a drop on the 2 bronze bushes in a free standing one ) or more likely a small capacitor inside busy dying. It is a 3 wire unit and is a common fault in both ceiling and free standing fans, and is a common fault ( almost built in failure so you go out and buy a new one) and is cheap to replace, costing about 2 quid. It is small, black and has 3 wires, typically white, yellow and red coming out of it. A new one and a drop of motor oil and the fan runs like new again.

 

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