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ogre2011 05-26-2011 06:45 PM

Wiring fan to capacitor
I have the following:

FASCO motor D7908
6 wires total: (As it is stated on motor sticker"
purple and yellow are set up for rotation of motor


GE Capacitor 97F9895

3 sets of prongs:

"C"ommon has four prongs
"HERM"itic has 3 prongs

I just need to know which wires from motor plugs onto which prongs for capacitor.

My house is at almost 90 degrees and I have no air so in other words...PLEASE HELP!!!! My fiance' is getting awnry!!!:furious:

Thanks in advance!!!!

hvactech126 05-26-2011 07:22 PM

did you get a new capacitor for the motor? The capacitor you describe is a dual-run capacitor for both fan and compressor. When replacing a motor ALWAYS replace the capacitor as well. Often new motors require a different value capacitor than the original.

Marty S. 05-26-2011 07:26 PM

Best to use a seperate capacitor as stated. For now though hook the brown to the fan and tape off the brown with white stripe.

ogre2011 05-26-2011 07:26 PM

Did not
It is the same exact motor and capacitor set up....problem is, a friend came over to remove motor to go get a new one for me while I was at work and he did not bother checking what went where.

hvactech126 05-26-2011 07:32 PM

is it a new capacitor?! The motor is obviously aftermarket due to reversible rotation. Check the label on the new motor for the required capacitor. Then check the capacitor for its value rating on the label should be similar to 35/5 or 35+5.

ogre2011 05-26-2011 07:34 PM

I replaced the motor with the same exact one that came out of it and the capacitor that was in the HVAC unit is the one that ran the old motor.

hvactech126 05-26-2011 07:37 PM

great, go get a new capacitor so you don't ruin the new motor. But I would still look on the motor label for the required capacitor value and get the correct size one required for the motor. If you want it to run right now

white to com on capacitor
black to contactor (opposite side than the one connecting the contactor to the com terminal)
brown to fan on capacitor
brown/white - tape and cap off.

ogre2011 05-26-2011 07:43 PM

Ok, I can get one tommorrow, it is 845pm here and my house is still at 83 degrees.

If I get a new capacitor, I am guessing it will be one with only 2 sides with four prongs each. In that case, what wires need to go where?

hvactech126 05-26-2011 07:47 PM

black to contactor
white to other side of contactor
brown to capacitor
brown/white to other side of capacitor

ogre2011 05-26-2011 07:52 PM

Ok, thanks for the info.

Just curious, why is there 2 brown wires if one of them is useless?

The motor is a "split capacitor" type motor, so what does that mean?

hvactech126 05-26-2011 07:57 PM

its not useless, it is used when there is a standard single run capacitor used for the fan only. I just gave you that information where both brown wires are used.

ogre2011 05-26-2011 08:10 PM

Guess I was just confused since using the old capacitor I would only use the solid brown wire and not both it and the BR/WH wire like the old one had used on the same capacitor.

IF I can get a capacitor that is the right size can I wire it as so, run the white wire through the original COM on the old capacitor as to not have to disconnect the other 4 wires that are attached and just run the 2 brown wires seperate to the new capacitor?

Again, thanks in advance for the help....I can fix multi-million dollar fighter aircraft but the technical stuff such as this is not my cup o' tea and I can use as much help as I can get!

hvactech126 05-26-2011 08:30 PM

I think you are trying to over complicate it and in the process you are confusing me as to what you are asking. I have a few different pics that may help.

ogre2011 05-26-2011 08:45 PM

I will try and post some pictures of it in the AM, I can't see my hand in front of my face outside right now.

I got every fan in the house on and am going to re-attack in the morning....

Do not mean to confuse, just trying to understand myself.

Will post pics ASAP and see if you can understand where I am coming from.

ogre2011 05-27-2011 12:08 PM

1 Attachment(s)
I am attaching pictures of what the system control section looks like.

It shows the old capacitor in its original holder with the blue and yellow wires running up to the ceramic deal and then onto the compressor set up. I have temp hooked the brown wires to a capacitor for picture purposes only to see if this set up will in deed work and not damage any of the equipment.

Will this set up work or do I need to move other wires around and get rid of/add something else to ensure this set up will work.

Any and all help would be greatly appreciated.

As it sits right now, I have the white wire from motor going to COM on original capacitor, I left the yellow wires attached to the same spot and the blue wires are on the HERM port of the old capacitor. All I did was move BOTH the brown and brown/white wires over to a different capacitor.


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