I am in need of an old obsolete part number for the compressor start relay on my old whirlpool refrigerator. I can’t help but think that somewhere out there, someone should have an old parts list for this model . I just need the part number to cross reference to a new part.
You can install a URO41 (AP4503418) start device, comes with instructions. This is a very old unit, can’t find info for it. You just plug the unit in and use spade terminals on the input refrigerator wires.
I assume it is between 1/4 and 1/3 hp, current draw between 1.5 to 3 amp. I also assume the compressor terminals are in a triangular configuration with common on top, start terminal on bottom left, run on bottom right. This is the standard configuration.
Let us know if you have problems with it.
Thanks for the information, what is the difference between the uro41 and the upro41? Since your response, I have found an article written by you (Richappy) titled “Replacing compressor start devices” where near the end of it you mentions the upro41 is safe in 90% of all compressor’s. It just has the same problems as the uro41. So which one is the best one to use in my situation? The terminals are in a triangular configuration with the common on top, start bottm left, run bottom right. The Tech sheet that came with the fridge shows that the ohms for common to start terminals should be 6-22 ohms, mine is 7.23 ohms. Common to run should be 1.5-6 ohms, mine is 1.51 ohms. I did have a different old start relay on hand and hooked it up to see what the amp pull is. Using my Fluke multimeter with capture mode this is what I found. On start up it pulls 27.6 amps and immediately goes to 3.9 amps where it stays while operating. The fridge tag with the model number and serial number also says its 120v, 60HZ, single phase, 6.8 amp, 720 heater watts. The overload device has part number 548474 on it. Anything you can tell me would be appreciated to get me up and running.
[quote=richappy;352756]You can install a URO41 (AP4503418) start device, comes with instructions. This is a very old unit, can’t find info for it. You just plug the unit in and use spade terminals on the input refrigerator wires.
I assume it is between 1/4 and 1/3 hp, current draw between 1.5 to 3 amp. I also assume the compressor terminals are in a triangular configuration with common on top, start terminal on bottom left, run on bottom right. This is the standard configuration.
Let us know if you have problems with it.[/quote]
The UPRO41 is very easy to use, just plug it in and comes with directions, the URO41 is not a plug in and you must verify compressor pins to wire it up. Both are inferior devices, easily burn up during power surges.
The discrete ptc start device and klixon are much more reliable. In my service work I have NEVER seen one of these burn out, just a very good thermal design, but you must wire them up properly or you run the risk of compressor burnout. When I use them, I triple check to make sure the power does not go directly to the start winding, or you will blow it out.
You have a 1/2 hp compressor, so you probably should use the URO21, designed for for 1/3 to 1/2 hp compressors if you elect to use that device. It delivers more starting current and has a higher klixon trip current.
To use a discrete ptc device, I would have to search for one as that device was developed for the newer, high efficiency, low hp compressors, it just might not be available.
If you use the URO21, you should use a 1000joule surge protector to prevent burnout.
Your compressor will probably not burnout if you misswire it, I think it was appliance man who wired one up wrong and it didn’t burnout. The older compressors are impedance protected, they do not draw huge currents when wired up wrong.
I searched and could not find ptc info, you can order the AP3414961 ptc and the klixon AP206490, they are cheap enough.
Thank’s for the ino, I used the URO21 with the surge protector and it works great.
Very good, glad to hear it, just never use the hard start kit called a 3 n 1 hard start kit, they have been known to catch on fire!
I have successfully used Supco 3-in 1 RC-410 and RC-810 start relays, but not the ones labeled hard start kits. Are there any problems with those models?
Any hard start unit with a start capacitor in it is unsafe to use. It will say on the package it increases starting torque which means it has a start capacitor in it.