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soulcaliber
Aug 9, 2007, 01:46 AM
Im having a problem figgering out where these wires go on my 2 prong contactor I have 2 violet wire and 2 red wires and a black and red wire I've looked and looked and found no giudes or diagrams showing where they go can anyone help me :confused:

Stratmando
Aug 9, 2007, 10:06 AM
2 pole contactors, Have Line power in 1 side, and when energized it will feed power to equipment. The 2 violet wires may be the 24 volt control. Can measure with meter, when set to cool or setting that it controls. With 1 pole(Don't personally like them) One line will always connect to load. It just bypasses 1 side of contactor.

acetc
Aug 9, 2007, 01:24 PM
Normally the wiring diagram is on the access panel of the a/c, just to add to the above advice, a single pole contactor will have two terminal screws on both sides of it ( 4 screws)
The incoming two wires will connect to one side of the contactor, the two wires that are factory installed wires will go to the opposite side of the contactor, and if the purple wires are small and come from the thermostat wires then they will go to the contactor coil,this coil is in the middle of the contactor and will have spade connectors (2) one for each wire.
The purpose of single pole contactors are to provide a bleed voltage through the capacitor during the off cycle and keeping the compressor warm to prevent the refrigerant from mixing with the compressor oil and chasing it out of the compressor, this is an important thing that some people overlook when changing a contactor . Good luck, Mike

J Costa
Aug 10, 2007, 04:55 PM
Good answer acetec

Stratmando
Aug 10, 2007, 05:14 PM
Acetc, I always wondered why they would break one side. I always thought they were Just Cheap. Where does it bleed through? Don't doubt anything. Just want to understand.
I actually changed out my single pole contactor to double pole contactor when it went bad.
It Has been hanging in there(Knock on wood). Take Care.

acetc
Aug 10, 2007, 06:40 PM
They bleed through the capacitor that will feed voltage through the run and start windings of the compressor. The capacitor changes the phase from the run to the start side of the capacitor .
You can put a jumper across one side of the contactor and accomplish the same thing.
This way of keeping the compressor warm during off cycle was probably to save money during manufacturing, you will notice they don't come with an internal or external crankcase heater when they have the single pole contactor.

Stratmando
Aug 10, 2007, 06:51 PM
Thanks, I am in Electrical/Electronics, Just curious, Take Care

doctorx
Sep 1, 2011, 08:19 AM
I just replaced a burned out contactor on my carrier unit. The unit will still not come on. When you push the contactor in manually the unit and fan come on but will not stay on once it is released. Could it be the capacitor?

Tz

Stratmando
Sep 1, 2011, 03:18 PM
No, Capacitor is fine, you need 24 volts to the outside compressor contactor coil this comes from the thermostat via Air Handler , which is where the 240 to 24 volt transformer and fuse are. Turn off power when working inside if competent, they can kill.
If the thermostat still operates the inside blower, transformer and fuse are likely good and you may just need a contactor if 24 volts is present and it doesn't energize(pull down)