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Where do the wires from the thermostat attach to an outdoor Payne AC condencer unit ??

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  • bsassanel790 Aug 24, 2010

    I guess that I need a location on the condencer (sp) . My wife was weeding around the back of the unit and by mistake yanked the wire out and I cant find a place to re-attach it.. can you help ???

  • bsassanel790 Aug 24, 2010

    All that is well and good BUT it is not the thermostat that is in question. I need to know where the two leads of the thermostat wire should be connected to the condensor unit. As I explained before, this wire was pulled from the unit while weeding around it.

  • bsassanel790 Aug 25, 2010

    Thanks for your efforts but my problem is still that I have no idea where inside of the condensor unit that I should attach this wire (two leads) that were pulled out by mistake. The unit (condensor) is a Payne. I am not sure of the model but it is not a very large one. Is it dangerous to let the System run without the control wire attached as the fan in the outdoor unit isn't running while the unit in the furnace is???

  • bsassanel790 Aug 26, 2010

    Yes and thank you


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Your thermostat wires will go directly to your furnace, then from your furnace they will go to the outside condenser. Without knowing what model and year furnace you have, or if it's a heat pump system or not, I can't tell you exactly hoe they hook up. For most units now, they have a electrical board inside the furnace that all the thermostat wires hook to. The terminals will be marked for each wire. The condenser wires will usually be connected to the Y(Cooling) and C/B (Common) terminals. Now if you have a heat pump system, it can be a little more tricky. Your standard split system will have 2 wires (usually Red and White) going to the condenser, while your Heat Pump will have up to 7 wires and will sometimes connect to a box before going into the furnace. Like I said, it's difficult to tell without knowing what furnace and system you have, but hopefully I have already answered your question. Hope this helps and good luck!

Posted on Aug 25, 2010

  • Brandon Berry
    Brandon Berry Aug 26, 2010

    I'm sorry it took this long to respond, the business is still really busy right now. The wires you are referring to connect to two wires inside the electrical panel on the unit. They will usually be in a separate compartment (small metal piece separating them), but not always. You should see either two bare wires close together or possibly two wires with wire nuts on the end if they did not come off. It doesn't matter how the wires hook up as they will work both ways. But no, there are no terminals they connect to, just two wires that hook up to the two going to the unit. Sorry for the misunderstanding and the time again. If you have any other questions, I will try to respond as fast as possible.


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That varies from model to model, contact Payne customer support for instructions for your paticuliar AC unit

Posted on Aug 25, 2010

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The wires going to the condensing unit are shown as red and white however these colors can be different. The important part of these two wires going to the air conditioner condensing unit is that the one wire orginates from the thermostat Y terminal and terminates at the condenser and the other wire originates from the common side of the transformer which is most commonly installed in the air handler. On rare occassions the transformer can be found in the condensing unit not because the manufacturer installed the transformer in the condenser but because the transformer was blown and replaced in the condenser instead of the air handler. Additionally, the colors here are typical but can be different depending on who wired the unit and their color coding system. 99% of the HVAC technicians will use this color code but there is an occassional oddball who knows better than everyone else or the wiring color combination was not available for the wire used to wire the equipment.

Take care.

Posted on Aug 24, 2010

  • Jimoh Adeleke Muyideen Aug 24, 2010


    • Red to the thermostat RH or thermostat RC terminal with a jumper
      wire between thermostat RH and thermostat RC. Or Red to the
      thermostat R terminal which is shared with both the heating
      and cooling. It has an internal jumper built in to the
      sub-base. The red wire is the source hot wire from the
      transformer. All other wires, except the common wire, controls
      a specific relay or contactor that energizes the fan, heating, or
      cooling depending on the selection. The following is the
      common wiring colors but your system may not be common and
      different colors could have been used.

    • Green to the thermostat G terminal. This is the color that controls the fan or the relay that control of the blower.

    • Yellow to the thermostat Y terminal. This is for control of the air conditioning.

    • White to the thermostat W terminal. This is for control of the heating.


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Generally, you would go from the thermostat to the air handler, and then, from the air handler to the outdoor unit. I don't know if you have a heat pump or not, so I will give you a simple diagram and you can contact me if you need more.

Thermostat : Y G R W and sometimes C
Air handler: Y G R W and C
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Thermostat; Y--------------Y(air handler cooling)------------------one side of contactor, outdoor unit
G-------------G (air handler, fan)
R--------------R (air handler ,hot)
W-------------W (air handler, heat)
C--------------C (air handler, common)------------other side of contactor, outdoor unit

This is a typical wiring diagram. Just contact me if you have something different. Hope this helps. Stay cool. mark

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