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mike bruner
Sep 12, 2012, 09:17 AM
I have a 4 ton coleman package unit. The compressor failed under warranty. We took it out took to dealer they said they were having trouble with this particular compressor so they opted to give us another. However the new one has 2 black wires coming out of the bottom and no wires at the little black box terminal that has the three prongs marked ST2 CT1 and R. I do not know everything about A/C however have done a little. The new compressor is a Bristol mod# 22J41 BABCA. I know there should be 3 wires coming from that little black box. One to the capacitor one to load on the contactor and not sure about the common wire. I think its to keep compressor from overheating. I need to know how to terminate this compressor to make it work. Currently we have the two black wires running to the contactor nothing happens when we push it in. I know its not right. Can anyone share any ensite on what needs to happen? It would be greatly appreciated. Also the capacitor is new. It has freon in the system as well. I has to be electrical I am thinking. Thanks for any help.

mygirlsdad77
Sep 12, 2012, 04:51 PM
The two black wires are for an internal overload, that is externially wired. Here you would take one of your 24v contactor coil wires (themostat wires) and hook it in series with the two black wires. This will cause the low voltage to drop out if the internal overload of the compressor opens, which will in turn open the contactor of the condenser, in turn shutting the complete condenser unit down until the internal overload of the compressor resets. You could merely tie the two black wires together, but this would eliminate the compressor saving effects of the internal overload, and void any warranty. Up to you. Please let me know how things work out.

mike bruner
Sep 13, 2012, 08:44 AM
So how do I terminate the three connections at the compressor marked st2 ct1 and r? Thanks so much.Mike

mygirlsdad77
Sep 13, 2012, 03:50 PM
Hook the r to load one of contactor, hook ct1 to load two of contactor, hook st2 to herm side of capacitor.

mike bruner
Sep 13, 2012, 03:59 PM
Awesome man you have been a big help. The electrical stuff stumps me every time. To be clear the two black wires go to any two of the stat wires correct? I definitely want the overload to work. Again thanks so much for taking the time to help me out man. Mike

mygirlsdad77
Sep 13, 2012, 04:08 PM
Yes, either low voltage wire will work. Take your pick. So instead of running one of the stat wires directly to the contactor coil, you run it to one of the black wires on the compressor, then run the other black wire on the compressor to the spot on the contactor coil where the stat wire would have hooked. Hope this is all making sense. Im no electrician, just so used to working with these things that its kind of second nature. Don't ask me to wire a home for you or anything, but the basics of heating and cooling equiptment, that I can do. Take care, and I hope it all works out smoothly.

Grady White
Sep 14, 2012, 06:07 PM
If those two black wire come out of the bottom of the compressor, chances are they are for a crankcase heater. Overloads are usually on the top.

EDIT: Checked Bristol's website. Those wires coming out the bottom are indeed for a crankcase heater. If you choose to use it, connect them to the line side of the contactor. One black wire to each of the line terminals.

mygirlsdad77
Sep 17, 2012, 03:46 PM
Good call Grady. I didn't pay attention to the "bottom of the comressor" in the original post. I just got overload stuck in my head. Glad you came along to catch that one.

Grady White
Sep 17, 2012, 06:33 PM
Hey, I wish I could say I hadn't gotten tunnel vision myself & on more than one occasion.
To err is human. To really foul things up takes a computer. Peace