Tip & How-To about Refrigerators

Pins on the compressor.

If you have an ohm meter you can test the compressor in your equipment. There are three pins on the compressor. Start, Run and Common. The common pin is the pin that is by itself while two are either above it or below it.
First thing to do is check for grounds. From compressor body or tubing to each pins seperatly, You should get no reading on the pins to ground. Now that you have done this, you can check each winding for open, and check the resistance on each winding. With you meter one leg on common and you can pic any one that is left, it will only be either the start winding or the run winding. Measure the resistance and write it down, If you get no reading, the compressor is scrap due to open winding. Then go to the next pin and check it for open if you get a reading right it down. Between the two numbers that you have the comon and whatever pin has the lowest reading is the run winding. The pin with the highest reading is start winding. Now add these two numbers together and take your meter and measure pins start and run, they should equal the two numbers that you wrote down, hope this helps. A rating would be cool.

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Replaced capacitor and start relay. now the compressor clicks but wont start. is the compressor bad. replaced thermostat and heater also


you can measure from pin to pin on the compressor connection with an ohm meter, the two small numbers should equal the large number if not bad compressor start to run = start to common=and run to common=

Nov 05, 2015 | Maytag Refrigerators

1 Answer

Please identify compressor connections. Original = red to low, white to high left, nothing on high right. New 3n1 has black (common) and red (run) white (start) and twin black power lines.


The three compressor pins are shaped in a triangle, the common is either directly on the top or directly on the bottom depending on the compressor. The wires of the supco are installed with the red to run, the white to start,and the black to common.(If the common is directly on top, run is lower right and start terminal is lower left) (If the common pin is directly on the bottom, the run is on the upper left, and the start is on the upper right) When you cut out the bad relay overload, the wires hook on the two black wires of the supco with bare ends.

Check for full 120 volts at the outlet, important.
If you have a meter you can ohm out the compressor windings, the run and start are connected to the common. It is easier to explain looking at a picture, so good luck.......... Picture a triangle with three letters c for common, r for run, and s for start........

The other thing to remember is there is a new type of compressor(some variable speed new one I am unfamiliar with) that does not use this setup, check the schematic(95% will) Consider if you still have a warranty on the compressor also. Supco also sells a 3n1 with a hook up for the old capacitor on its part, very handy, just plugs on, you do not mention it, so probably not the one you have. If you get your compressor running and it sounds good, do not buy a fridge full of groceries for a week or so, compressor may fail, let it run for a few days first, hope this helps,
good luck and do not forget to unplug when working on it..........

This is basically general information for a older refrigerator out of warranty....
Also consider the possibility of what could go wrong if you are not sure of your work, do not attempt this if there is a strong burn mark from old electrical s, replace compressor and or buy a new unit.

Mar 16, 2011 | Whirlpool Refrigerators

1 Answer

Then refrigerator and freezer are not operating. I suspect the compressor relay P/N 61006293. When I read across the female pins of the relay with an ohm meter I read a short. Should this relay read short or open when checked across both pins? Also what is the effect of the $TM Overload and how can it be checked?


what you are checking in the female pins are the start and run winding at the same time. first check compressor with a meter. go from common to start, then common to run, add these two together and if you go from start to run you should get this total, let me know.

Mar 12, 2011 | Maytag MSD2756G Side by Side Refrigerator

1 Answer

Refrigerator keeps tripping the breaker and not blowing.


Good day,
Usually 2 reasons for this problem.
1. The compressor. Unlpug machine. There are 3 pins sticking out of the compressor body. Remove all the start components to the compressor so the pins are exposed.
You will need an ohm meter to perform the test.
With the ohm meter set to any of the higher settings or if it is digital put the probes together to make sure it zero's out.
Take one probe and place it on any pin. Take the other probe and find a bare copper (clean) pipe coming off the body of the compressor. Take a reading. It should read infinity or near infinity (no resistance). If you get a reading on that pin or any of the other 2 you have a grounded compressor that needs replaced.

If the compressor checks O.K. remove the rear cover in the freezer compartment. There is a calrod heating element that runs along the bottom of the cooling coil. Unplug both ends.
Plug the machine in and turn it on. If it appears to start and run O.K. it's a shorted heater, and needs replaced.

If neither of these items solves your problem. Post back. They are the common items in this situation.

May 20, 2010 | Kenmore 55612 / 55614 / 5561 / 655619 Side...

1 Answer

Kenmore Refrigerator 106.53502300


sethjames,the relay can fail and the compressor could still be fine.as a serviceman in your home i would pull off the relay and ohm out the compressor.their are three pins.i would put a meter probe to ground[scrape the probe into the metal of the compressor]and then touch each pin with the probe one at a time.you should get no reaction on you meter,if yes, then the internal motor windings are shorted to ground.now if that test's ok,next you put one probe on the common pin[most brands its the top of a triangle formed by the three pins]and the other would go on the start or run pin.the measurements/or readings would be like this if normal.common to start winding from about 1.0 ohms+- maybe .3 ohms,common to run wining about 1.5 ohms+- .3 ohms .the newer more efficient your compressor the lower the numbers the older the unit the higher the numbers,because the energy standards were less .if readings in the 3.0's that's not good [although ive seen boxes that were 15 to 20 years old working fine and were drawing about 4 amps],so resistance,ohms would be higher [dont mean to confuse you there mixing ohms and amps].also if you had an amp probe you could clamp it over one wire and that would tell you how hard the compressor is working.should be about one amp in the run winding[in a newer box]on my truck i carried a universal relay that was rated for certain horse power.it was best for me ,then only needed one part for all makes.wholesale in 2007 it was less than 10$.with on line access it may be just as easy for you to get the original.but i would think twice if cost was quite abit higher.i hope that helps abit ill be there if you need more advise God bless ,tom

Feb 03, 2009 | Kenmore 53082 / 53084 Side by Side...

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