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Trouble-Shooting => Refrigeration => Topic started by: briandr1 on January 17, 2011, 07:45:44 pm



Title: comp question
Post by: briandr1 on January 17, 2011, 07:45:44 pm
If I was to hook up the condensor fan at the same place where you supply power to the 3 and 1 starter could that harm the 3 and 1 starte. I did it that way while the deck was out of the machine and it ran fine compressor and fan both, ran it for 5 min. Then  I put the deck back in the machine and the compressor wont start anymore but the condensor fan does. Any sugestions???  :down:


Title: Re: comp question
Post by: johnieG on January 17, 2011, 09:24:19 pm
No. hooking up the condenser's fan motor electrical leads to the input lines of the 3-in-1 is actually the correct way to do it ( the fan & 3-in-1 in parallel ) if the compressor won't run, but the compressor doesn't, then somethings wrong with the compressor, make sure your connections are still in place on the compressors terminals & didn't come loose,

you should also check your compressor for an open "start-winding" with an OHM meter ( power off, & all wires disconnected from the compressors terminals) there are several discussions you can search for on testing a compressors electrical windings if the unit checks out OK electrically, then the compressors beyond a simple 3-in-1 fiz.


Title: Re: comp question
Post by: briandr1 on January 17, 2011, 10:18:46 pm
I will do I think its a lost cause though. I hooked up the 3 and 1 directly to a cord  to isolate it from the rest of the machine didnt start and when i touched the condensor I felt an electrical shock not a big one but none the less a charge what could cause that ground bleed? anyway thanks for your help John. looks like new deck time.


Title: Re: comp question
Post by: briandr1 on January 18, 2011, 06:58:44 am
To test the windings you add C + S and C+R  then R + S must be equal to the sum of C+S and C+R correct?


Title: Re: comp question
Post by: johnieG on January 18, 2011, 12:29:30 pm

run to start terminals Ohms reading has to equal the sum of run to common plus start to common

also take a reading from each terminal to the compressors chassis/dome ( scratch through the paint to bare metal) any reading less than 10-meg ohms, junk the compressor, it has a shorted field winding. 


Title: Re: comp question
Post by: briandr1 on January 18, 2011, 01:35:22 pm
Will do thanks for your help Ill let you know how it tests out.


Title: Re: comp question
Post by: briandr1 on January 18, 2011, 08:35:39 pm
Well I have to wait on a friend of mine who has a mega ohm meter he cant make it till tomorrow, have you ever had a new 3 and 1 just go bad although its new this one I have doesnt test right it wount build up when I test it and wont discharge when I  reverse the leads its a surpco brand are the any good and I dont know for shure if its a 1/4 or a 1/5 hp compressor do you know off hand what hp the comp is in a cavalier 96. The tag on the evap doesnt say and the tag on the body is missing.


Title: Re: comp question
Post by: johnieG on January 18, 2011, 09:54:14 pm
3-in-1 starter/run boosters rarely go bad except when overloaded, ( too small of a rated unit on a compressor that's too large [H.P. wise] ) as in example, if you put a 1/3 HP rated unit on say a 1/2 HP compressor.

Conversely, if you install a 1/2 HP unit onto a 1/4 HP compressor, it will cause the compressors start winding to over-heat as the solid-state start-run relay wouldn't have sensed sufficient current to cause it to switch from "start" to "run"....thus the compressor will start & "run"  only on it's start winding, which isn't designed to run at 100% duty-cycle


Title: Re: comp question
Post by: briandr1 on January 18, 2011, 10:05:09 pm
I get ya thanks for all your help I think even if I get it running again I wont trust it. I think I get a tune up kit which is a new comp condensor tubing and a drier Ive allredy changed both fan motors then ut will be good for another round. thanks again for all your help man. Ive still got my selectivend 64 sa working so my sodas are cold lol that machine is bullet proof!!!


Title: Re: comp question
Post by: briandr1 on January 21, 2011, 06:56:03 pm
I diid have a chance to test the comp the meter would test up to 20 meg ohms and both terminals tested over 20 meg ohms does that mean the field windings are ok


Title: Re: comp question
Post by: johnieG on January 21, 2011, 07:27:11 pm
generally yes, 20-Megs is fine,  but you should test all three terminals to the compressors dome. also did you test the terminal to terminal ohms reading? ( testing for an open start winding basically) once the resistance readings are complete ( assuming it all checks out OK) you could try to hook up the 3-in-1 starter again. & maybe do a current test to check for a locked rotor...


Title: Re: comp question
Post by: briandr1 on January 22, 2011, 03:54:14 pm
It tested 20 plus megs on start pin, nothing on run pin or common. got 18 volts resistance from start to run pins, nothing from start to comon or from run to commomn. but there is continuity from the start and common pins when you ground on the dome of the compressor. its shot for shure lol bummer.


Title: Re: comp question
Post by: johnieG on January 22, 2011, 07:54:26 pm
Yep. toe-tag it & time for a new unit.