PDA

View Full Version : Need Wiring diagram info on hooking up compressor


Peterb79
Sep 18, 2009, 07:09 PM
My Question is about checking the wiring on my A/C compressor and capacitor.
The compressor has five wires coming out of it and they connect as follows:

My compressor has a red wire and a black wire going to the top of the contractor.
Then it has a yellow wire going to the capacitor. The other side of the capacitor has a red wire connected to it and then this wire goes the red hot wire on top of the contractor,
Two wire total going to this capacitor.

Then two brown wires coming out of the compressor and each one is hooking to the bottom of the contractor where the power comes in with a black wire and a red wire.
Brown to red and brown to black. By this hook up, it is giving instant power to the brown wires and into the compressor it seems.

Then the fan motor has a white wire connects to the top of the contractor to the red wire prong.
Then the fan motor has a black wire connects the other prong on the top of the contractor.
Then the fan motor has two brown wires and one is connected to another capacitor and the other brown with also connects to the same capister on the othere side of it. Only these two brown wires are going to this capacitor.

The fan runs and starts up and the compressor is not starting up with this wiring hook up.
Any help appreciated on how to hook up the wires.
Thanks

hvac1000
Sep 18, 2009, 08:58 PM
Exact brand and model number of unit? We cannot do much without it.

NOTE all units come with a wiring diagram. In many cases this diagram is on the backside of the outdoor units service access door.

Peterb79
Sep 18, 2009, 09:27 PM
I hve not been able to find any brand name on the unit. It is a 5 ton unit.
Is there a basic diagram for the wires coming out of the compressor.
My most concerns are if the two brown wires should be connected to the incoming power two 110 screws as this is before the contractor and gives live juice into those two brown wires.
My other concern is how many wires should be connected to the larger capacitor that has the yellow wire from the compressor hooked to it and the othere post on the capacitor goes to the hot plus 110 post at the top of the contractor.
Thanks for your help

hvac1000
Sep 18, 2009, 10:07 PM
Im almost hate to say this but to be honest you are way in over your head on this.In many respects color code means nothing unless you have the factory wiring diagram.
I can guess at this much

The two brown wires are probably for a crank case heater that is built into or wrapped around the compressor. Those wires are supposed to be powered at all times.

How many wires should be connected to the large capacitor is a good question since I have no idea exactly what the capacitor does in the no name unit you have.

It could have two wires to 4 wires depending upon if it is a dual capacitor one side for the compressor and the other for the fan etc.

As always the information I posted here is a GUESS because I do not have a wiring diagram for your unit.

Peterb79
Sep 19, 2009, 08:38 AM
Thanks for the information. I know that I have not given all of the info I should have.
My fan motor went out on the condenser unit. I purchased a new one and the seller gave me a two prong G.E. -OV-10-370 capacitor and told me to connect the two brown wires to it.

Before, the other motor has been connected to the three prong capacitor that is much larger and the number on it is: 5/45 --440 V--25/85/21-P2 This old capacitor is leaking wax out of the top and one of the prongs is burned and warped.
Should I get a new larger cap and not use the small GE one and connect the two brown wires to the larger one as was before.
I installed the motor and left the other wires, yellow from compressor and red from the contactor on the old leaking capacitor.
When I turned the circuit breaker back on, the fan motor started back up and ran, However, the compressor did not kick on.
Now I do not know if the bad leaking cap is keeping the compressor from kicking on or is it the fact that I am now using the other capacitor on the motor and this is keeping the coimpressor from coming on.
Thanks
Peter

hvac1000
Sep 19, 2009, 09:12 AM
First of all you need to use a capacitor sized for the fan motor you have now.
Next you need to obtain a new capacitor for the compressor since it is leaking oil and if not defective right now it will be shortly.

Now it might be possible to find a dual capacitor that has a the correct MFD for both the new fan motor and the compressor OR you can use a single capacitor for the compressor and then the single one you already have for the new fan motor.

The wiring could be keeping the compressor from coming on at this point or it could be the leaking capacitor.

Here is a wiring diagram for a outside unit. Use it for the line wire diagram not for the color code since your colors of wires could be different. It shows a 3 terminal capacitor but the diagram will need to be modified to use two separate capacitors.

http://www.nordyne.com/literature/710570b.pdf

Peterb79
Sep 19, 2009, 11:12 AM
Thank you for the diagram. This explains it to me. My son has a 5 ton outside unit that I can rob parts off. I pulled the capacitor from it and the label reads:
80 + 10 uf 370 V 50/60 hz 70c It is a 3 prong part.
The capacitor that I have have that is leaking could easy not be the correct one as the local repairman just home town rigs a lot of his work as I live out in the country in a rural section. So the one that is leaking is marked 5/45 uf 440V 50/60 hz.70c

The one that I pulled from my son,s unit is not leaking and the unit was running when he took it out for remodel.
I do not know just what number I would need as as I said, the one in there is not original and the repairman does just rig up to get it cooling.
Can the wrong cap hurt the system to try it.
Thank you again!

hvac1000
Sep 19, 2009, 12:08 PM
YES it can hurt the system. The higher number capacitor 80/10 is from a Scroll Compressor and the 45/5 one is from a piston drive unit. GET the correct capacitor or the exact replacement that was in the unit which was 45.

If you really feel it might have been replaced with a incorrect one you can do a Google search with the compressor part number and find the exact value it is supposed to have.

Peterb79
Sep 19, 2009, 12:55 PM
Thank you. The information plate on the top of the compressor has many numbers on it.
First number is BM703007 Protected
V 230-208
Hz 60
LRA 142
H23A563ABCA
Sn 00588193988
Made in USA
There is a sig that looks like OB with Cmpressors stamped over the OB or DB, just can't read it}
Also has a painted type larger numbers which is: 180733 and another painted one is 9211-294
I will attempt to find this on Google and really thank you for all your help.


The motor that I installed reads V 208-230
Amp 3.7
RPM 1075
HP 1/2
Hz 60
Compacitor 10mfd370vac

Peterb79
Sep 19, 2009, 12:57 PM
Sorry on the motor info should be capacitor 10 mfd 370 vac

hvac1000
Sep 19, 2009, 02:50 PM
See bottom of page 9. Your compressor is listed there BUT it says 55 MFD at 440 volts for the run cap. Since you do not have a model number or brand of unit available it still could be a 45. NOTE it is a piston/reciprocating type.

http://www.nordyne.com/literature/8569%20Compr.pdf (http://www.nordyne.com/literature/8569%20Compr.pdf)

Peterb79
Sep 19, 2009, 03:04 PM
Been on the Google for hour and cannot match any of the numbers on the compressor. It is over 25 years old.
A couple of more questions,
If I leave the fan motor connected to the 0V 10 capacitor as the motor chart shows to use the 10 MFD 370 capacitor, then will the old three prong capacitor work with only the yellow compressor wire to it and the red wire to top of the contactor .
Looking at the three prong capacitor there are three marking on it where the clips attach.One reads C, one reads fan and the other one reads herm. I assume the yellow compressor wire goes to C and the red power line goes to herm. Would this work to get some air started today on me.
One more question on the three prong cap.
If the reading printed on it says 45/5, is the 5 for the fan start up part and if the motor asks for a 10, would the 45/5 be too low on the end where the 5 is. Or does 5 mean something else.
Thank You,
Peter

Peterb79
Sep 19, 2009, 03:19 PM
That is great news that you found the compressor. I just did not know where to look.
So what I need is to buy a 45 or 55 mfd cap for the compressor and connect the two wires , compressor yellow and red to power at the contactor and I should be fine.
Thank you,
Peter

Peterb79
Sep 19, 2009, 03:22 PM
I do not know if it a piston type. It is over 25 yearl old.
I know that every time it shuts down from running, there is a loud metal sounding bang, not explouding type just metal to metal sound.
It has been doing this for last couple of years.

hvac1000
Sep 19, 2009, 04:09 PM
The noise might be a broken internal compressor spring but as long as it runs in your case who cares.

I posted a wiring diagram before. Look at it for your wiring but do not use the color code since I do not know what colors go where on your unit but most units are the same. Just use the wiring diagram as a line diagram. Good luck