Author Topic: How do you check a compressor to see if it is good?  (Read 10175 times)

Offline moderators night

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How do you check a compressor to see if it is good?
« on: May 16, 2009, 09:46:25 PM »
This one isn't on the recall list per Maytag today. I'm pretty sure that the relay is bad (rattles), but before I buy a relay, I'd like to be sure that this compressor is good. Should you have continuity or not? I checked it with one meter, and it zeroed out. Then I checked it with a better meter, and it zeroed out, then gained some.
Anyway, how do you check it correctly?
Thank you!

Model MSD2456DEW

Offline jumptrout51

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Re: How do you check a compressor to see if it is good?
« Reply #1 on: May 17, 2009, 05:17:10 AM »
CSR...Can She Run.
With a meter set for continuity Check each pin to the compressor dome. Any reading the compressor is shorted out. Check each pin to the other and record the number.C to S and Cto R should equal S to R.
CSR...Common,Start,Run.
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Offline Repair-man

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Re: How do you check a compressor to see if it is good?
« Reply #2 on: May 17, 2009, 05:18:18 AM »
Here's a little insight about compressors....you can check the resistance of the windings all day long (until the cows come home), but even a compressor that shows good resistance on the windings can have a locked rotor. Only by installing a new relay/overload can you measure the run load amperage of the compressor while it is starting up.  There is no way around this.

Go ahead and invest in a relay or a 3 in 1 start kit.

Overload and relay for your model- part # 12002783
« Last Edit: May 17, 2009, 05:20:31 AM by Repair-man »
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Offline RegUS_PatOff

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Re: How do you check a compressor to see if it is good?
« Reply #3 on: May 17, 2009, 08:55:15 AM »
 :coffee:

attachment:
« Last Edit: May 27, 2009, 04:09:20 PM by RegUS_PatOff »
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Offline JWWebster

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Re: How do you check a compressor to see if it is good?
« Reply #4 on: May 17, 2009, 07:37:52 PM »
I actually have one of those cords,that is old school.
I use a Hard start.
« Last Edit: May 17, 2009, 08:36:07 PM by JWWebster »
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Offline MajorApp

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Re: How do you check a compressor to see if it is good?
« Reply #5 on: May 17, 2009, 08:27:18 PM »
 Are they for sale somewhere or do you have to make one?

Offline JWWebster

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Re: How do you check a compressor to see if it is good?
« Reply #6 on: May 17, 2009, 08:37:39 PM »
Mine I will have to dig up and see but I believe it is made by gemline
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Offline JWWebster

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Re: How do you check a compressor to see if it is good?
« Reply #7 on: May 17, 2009, 08:43:35 PM »
You would be better off to buy  hardstart and attach a lamp cord to it to check compressors.
May the hinges of our friendship
        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

Offline Icehouse

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Re: How do you check a compressor to see if it is good?
« Reply #8 on: May 27, 2009, 03:56:36 PM »

COMPRESSOR TEST CORD
I just use a steel (not plastic) 4 inch square electrical box (1900)  and a  cover with a fuse  for mine, with a grounded 14-3 supply cord going in and a length of 14-4 SJ cord coming out with an alligator clip crimped onto each of the wires (white, black, red, and green). And plastic boots on the clips. Also a short piece of 14/2 SJ cord with alligator clips and plastic boots.
I cut holes in the blank cover to accommodate a heavy duty (15A) on/off toggle switch and a momentary contact push button switch (15A). The white neutral supply wire gets tied to the white wire of the 14/4 SJ cord. This other end of the wire goes straight through to the compressor common alligator clip. The incoming green ground wire attaches to the green wire of the 14/4 SJ cord outgoing line. Using an  alligator clip to attach to the frame of the refrigerator.
The 'hot', black side of the supply, feeds first  through the fuse, then to one side of the  on/off toggle switch. The other side of the toggle switch is wired with the black wire from the 14/4 SJ cord and then straight to the 'run' winding alligator clip. From the output side of the toggle switch, a wire 'tail' also feeds the input side of the momentary contact switch.
The output of the momentary contact switch goes to one side of the 14/2 SJ cord the other wire of the 14/2 SJ cord will go to the red wire of the 14/4 SJ cord. The other end of the red wire will go to the compressor start winding alligator clip. The ends of the 14/2 SJ cord with the alligator clips can be clipped together or connected to a start capacitor.
To use, after verifying which compressor terminals are “common”', “run”, and “start”, just remove the relay and overload, and connect the alligator clips directly to the compressor. Plug the test cord into a grounded receptacle.
Turn the on/off switch on (you should hear the run winding's low hum), and hit the momentary switch to briefly energize the start winding just like the start relay does when it's working correctly.
If it starts and runs with a test cord, it usually means the compressor's OK. You'll want to test the windings with an ohmmeter, though, to be certain there are no winding shorts causing it to 'short-cycle' and run hot.
One of these cords can be handy for test-running other equipment, too. I often just loop the 'start' alligator clip back out of the way, clipping it to the cord, and use this to quickly attach to small motors, etc, to check them.
 


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Offline JWWebster

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Re: How do you check a compressor to see if it is good?
« Reply #9 on: May 27, 2009, 10:12:54 PM »
I have mine on a surge supressor/ cheap ass dollar store electrical strip. I hit the toggle and if the compressor is wank the pop up reset button keeps me from screwing in another fuse. dangit.them thangs done went to $4 for 2 of them at CVS. I have a shitload of them. somewhere.:D
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        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

 

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