# Whole house fan motor repair/replace



## JimP (Feb 8, 2002)

We have this vintage fan in a west window in our attached garage.
It sucks air from the tree shaded east end of the house all the way through beautifully...

Been in the family at least 35 years but the motor finally made a spark and died when I cleaned it and replugged it in this week.







(Web Image, not mine)
It's all steel and when fastened with long screws it is very secure to leave in the window...unlike the cheap plastic available today that a palm punch will knock them out.
The new ones do not have a thermostat either...
I've seen only one online, picture shown, but its gone....$175.00
There's another new one on Ebay for $125 but its the plastic version.

I need to have this one repaired - it's so perfect for the intended purpose....but there are a few problems.

1. It's a Sears Kenmore, 3 speed, Electr.reversible, but the model number is partially obliterated on the small decal inside...
the last numbers are 90270...if that's even a model #.
No other parts have discernable numbers either.
2. An intense search through Sears parts/models with that partial comes up empty, and even similar fans are so old parts wouldn't be available.

A couple of calls to motor and starter rebuilders haven't been returned.
There are a total of six wires going into the motor for all the configurations of speed and direction so it may not be a simple job, dunno.

If it can't be refurbished I'll be happy with a new motor and high/low in one direction - out - and the thermostat working.

With many of you being in the HVAC industry are there any ideas, someone in a garage doing rebuilds or places to call.
Someone have a working model just like it they want to sell, LOL.

I really don't want to start cutting holes in the wall for one of those shutter type exhaust fans.

Thanks in advance for any suggestions....


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## ih772 (Jan 28, 2003)

Check and see if one of the splices lost its insulating material and is now shorting against the case. The polarity reversing capacitor may have bitten the dust as well.

As long as a bunch of smoke didn't come out of the motor and you didn't burn up the windings it will be a very simple fix that you can be talked through.


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## JimP (Feb 8, 2002)

There were some sparks and a bit of smoke from inside the motor before I quickly unplugged it. Put it on the bench and plugged it in again later and drew a blank...nothing.


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## ih772 (Jan 28, 2003)

See if you unbolt the motor housing and take it apart in two halves. That will let you inspect the windings and splices to see what has happened. Take a bunch of pictures for reference as you disassemble it.

It sounds like a connection/splice has opened up and that would be a very easy fix. Had the motor windings burned up there would have been lots of smoke, not just a little curl of smoke when you heard it pop.


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## JimP (Feb 8, 2002)

Thanks, Stay tuned please. 
I'll pull it all apart next week when some traveling and other things get done.
Don't need it right now, Temps in the low 40's, :lol:
The high capacity stove vent is sufficient for the fried fish.


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## JimP (Feb 8, 2002)

Well I dug into it before the Lions game.
I'm no electrician but it looks like toast to me...
I blew out the crud from inside with canned air, the black areas are carbonized and crumble out easily...
Views are from both ends.








Looks like I need a new motor of some kind.
Just keep the metal frame and blade.
Anybody do this?

Stood it on end to slide the bottom on...little chunks of the washer like bearing fell out...


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## ih772 (Jan 28, 2003)

It looks like that one has been slowly burning up over time. Probably from the bearings wearing out. Larger industrial motors have over load protection to keep things like that from happening as they draw more and more current when bearings go bad. Not so on a little motor like that.

You should be able to find a new motor of similar size and ratings in the Grainger catalog.


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## JimP (Feb 8, 2002)

ih772 said:


> It looks like that one has been slowly burning up over time. Probably from the bearings wearing out. Larger industrial motors have over load protection to keep things like that from happening as they draw more and more current when bearings go bad. Not so on a little motor like that.
> 
> You should be able to find a new motor of similar size and ratings in the Grainger catalog.


No markings to even try and figure it out as to rating, rpm, whatever, plus every thing's permanently wired into the switches as a unit, would have to cut all the wiring to even remove it.
The six wires into the motor will be a mystery too...
Oh well, we gave it a shot.
Saw a Gable mounted attic fan with thermostat for $112.00, I just may have to cut a hole in the garage wall after all. ..:rant:

Thanks again...


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## N M Mechanical (Feb 7, 2008)

Go into a motor shop and see what price they will give you for a new one. Grainger will just look at you and ask you what part # you want
_Posted via Mobile Device_


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