OT---Fan Motor Capacitor

Jiles · Aug 29, 2016

I have bought two new vent fan motors and both stopped working in less then a year.
Old ones will spin free but not run. So I suspect the capacitors are bad.
I have searched extensively for capacitors but don't know exactly how to go about finding a couple.
Any suggestions appreciated.
I have no idea why motor tag states 3/4 when it is a 1/2" shaft?

4520BW · Aug 29, 2016

Looks like u need an 8 micro farad
capacitor.the black tag tells you
everything you need. I keep a couple of
the ones that work across a wide range
on hand.

Jiles · Aug 29, 2016

Where can I buy a couple?

Steve@Advance · Aug 29, 2016

Will they run if you give them a spin? If not, it's not the capacitor.

Says they have a thermal cut off. Is that a auto reset or a one time burn open? Be sure you are getting power to the motor. If the thermal cut off is open, there is a reason, the motor got too hot. It's a safety you don't want to bypass, fire hazard!

old · Aug 29, 2016

If you have an electric motor repair place in your area they should have them on hand. I might be one of the lucky one since we do have a motor repair place in town

Jiles · Aug 29, 2016

Haven't tried spin test, but I will.
Through research, I think I read it was a "run capacitor"

Jiles · Aug 29, 2016

At top of capacitor photo, you can see it has two "spade terminals".
Don't think there is a repair shop in my area.

Jiles · Aug 29, 2016

(quoted from post at 18:34:56 08/29/16) Will they run if you give them a spin? If not, it's not the capacitor.

Says they have a thermal cut off. Is that a auto reset or a one time burn open? Be sure you are getting power to the motor. If the thermal cut off is open, there is a reason, the motor got too hot. It's a safety you don't want to bypass, fire hazard!

I know it doesn't mean a lot, but there is no indication of motor overheating by sight or smell.

retired farmer · Aug 29, 2016

Does the 'Made In China' tell you anything about why they quit working?

Jiles · Aug 29, 2016

(quoted from post at 18:56:12 08/29/16) Does the 'Made In China' tell you anything about why they quit working?

NO ONE Dislikes China junk more then me.
Strange and disappointing that these china motors lasted ten years and the two replacement PACKARD motors stated on their tag "Made in USA" and didn't even last a year.
They don't have external capacitors.

Two Dogs · Aug 29, 2016

I have a squirrel cage blower in my barn . It quit and it turned out to be the capacitor. I searched for one and found an exact replacement on Ebay. About six dollars with free shipping where as locally I could have bought one for fifteen to twenty bucks. TDF

Texasmark1 · Aug 29, 2016

+1. You can just www a search engine with the numbers you see on the side of it for uf, ACV, values and notations afterwards including and you should get an eye full, possibly with the terminals you seek. If not, get out some spade lugs and make a couple of jumpers out of suitable wire...check the wire going to the existing terminals, 600v rated insulation and temp to match the cap. Find a convenient spot and RTV it in place or however you choose to mount it to wherever. If they aren't spade lugs, but probably are, get out your soldering iron and solder the jumpers.

Jiles · Aug 29, 2016

Will this work---
https://www.amazon.com/piece-Ceiling-Fan-Capacitor-Wires/dp/B00DTV83OC

Bob Harvey · Aug 29, 2016

Shows me that 'cheaper is better', China can make anything you want. There is some wrong thinking in the 'China Junk'. Retailers will do ANYTHING to make a profit. China is not the culprit, it is a huge country (larger in land mass than the U.S.) and produces anything you want for the price that will get you the largest profit, these are folks that can produce robotic devices that build our cars and such. Those guys don't care - you set the parameters and they will fill the bill. American consumers want low prices- Wal Mart- and don't really care about quality, most products bought are disposable. Haysoos, give your freakin' head a shake.

jeffcat · Aug 29, 2016

Ask anyone who does HVAC or heater service. They will have one right on the truck. Go for one a little bigger like 7MFD. or even 10MFD. Sorry to say but so many of these motors just plain crap out.

Jiles · Aug 29, 2016

(quoted from post at 01:22:20 08/30/16) Ask anyone who does HVAC or heater service. They will have one right on the truck. Go for one a little bigger like 7MFD. or even 10MFD. Sorry to say but so many of these motors just plain crap out.

Do you think this will work---

https://www.amazon.com/piece-Ceiling-Fan-Capacitor-Wires/dp/B00DTV83OC

Texasmark1 · Aug 29, 2016

High load starters are Cap start, (different) cap for run cap. Split phase (light duty) no cap. Regular duty, run cap only. The run cap is to keep the
power factor ELI the ICE man (E is field intensity now known as Voltage) within power company specs.

If the load is purely reactive [V (E) and I are 90 degrees out of phase, power factor = 0], no power is consumed and even though you are supplied
Volts and Amperes, it doesn't add up to watts consumed.....heavy torque loaded motors are bad about this with no C compensation. Gotta have
some R in the equation and to do that you have to add some C to balance the reactances. When the power factor is 1, the load looks like a
resistor, and the power co gets paid 100% for kWhrs supplied at the meter. I think a PF of 0.85 is the acceptable lower limit which, besides
transmission losses, they only get paid for 85% of what they send you. That's the way I remember it.

pete black · Aug 29, 2016

Well neighbor, if you can't fix it with a hammer, then you have an electrical problem.

Bob · Aug 29, 2016

Do the motors draw current/hum?

If NOT you are wasting your time and money trying new caps.

In that case, the caps MAY have failed first, then the motors stopped, drew excessive current, and opened the non-resetting thermal cutouts (TCO's).

W_B · Aug 30, 2016

(quoted from post at 18:34:56 08/29/16) Will they run if you give them a spin? If not, it's not the capacitor.

Says they have a thermal cut off. Is that a auto reset or a one time burn open? Be sure you are getting power to the motor. If the thermal cut off is open, there is a reason, the motor got too hot. It's a safety you don't want to bypass, fire hazard!

These fans drive me crazy. Llamas are a cool weather animal so we keep 8-12 fans going in the barn most of the summer. We pretty much gave up on the $40 20 inch high velocity fans that lasted about 1-2 years max. Llamas roll in the dust and drag that inside, so between the dust and constant running the won't last. We just use them at shows now. I have found the enclosed motor ones in 20" and 24" last many seasons.

I did have one 24" fail recently and had a 20" that kept destroying the blades for some reason. My bright idea was to swap the running 20" fan motor into the 24" one with the good steel blades and bigger housing. Got it done, set it in place and it ran about 10 minutes and it quit. After all that swapping and fixing the fan body I was upset. The motor was too hot to touch with a bare hand. I can only guess the motor wasn't up to powering the 24" blade. I did notice the black box (like the OP pictured) on the failed one was melted on the back side. I have a number of furnace fans with good motors that I'm going to put cages around to keep the llamas from getting into the belts and start using those too.

buickanddeere · Aug 30, 2016

Use an analog ohm meter set to resistance and test the caps.
If they are duds then replace with caps having both a higher voltage rating and a higher mfd rating.

OT---Fan Motor Capacitor

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