1

I am in the process of installing a new thermostat that requires a c wire. I checked my thermostat to see if it has a c wire running to it and it does not. After doing lots of googling and watching youtube video I think I know what to do but would like somedody that knows to verify it is correct before I attempt something like this.

I noticed where the wires run to the thermostat it has a extra wire (orange) not in use.

thermostat wiring

I then checked where the furnace to verify the same wire is not attached to nothing and it is not.

furnace wiring

If I am looking at it correctly I can connect the extra wire orange to the to the orange wire from the furnace which is not connect to anything (which if I am reading it right is the c wire) This would work correct? I am new at this and do not want to mess anything up.

gregmac
  • 28,726
  • 15
  • 82
  • 159
Jeremy
  • 11
  • 3

1 Answers1

1

It's a little unclear exactly what you're asking, but it sounds like you're on the right track. If the orange wire is unused (unconnected at both ends), you can use it as a C wire. Connect the one end to the thermostat's C terminal. Then connect the other end to the C terminal in the furnace.

If the furnace does not have a C terminal, please see this answer for help figuring out where to connect the wire.

According to the schematic, the grey wire should be C.

enter image description here

Tester101
  • 130,386
  • 77
  • 314
  • 605
  • Thanks, and just to be sure based on this picture (link listed below and zoom in to see the diagram in the back) the c wire is orange correct? Thanks, https://flic.kr/p/VXVpiZ – Jeremy Jun 20 '17 at 15:40
  • @Jeremy Umm... No. That diagram is for the blower motor. If you look at the rest of that label, you'll likely find a wiring diagram for the low voltage control wiring (which is what you're dealing with). – Tester101 Jun 20 '17 at 15:55
  • bummer, I tried looking and I am having trouble finding a diargram but I am not sure what I am looking at so I could be overlooking it..What should I do? The model is e3eb-017h. and Is the smaller thin wires that have the wire nuts on them the thermostat wires? I noticed they are the exact same colors that are under the thermostat itself. A full pic of what I see when I open the door is below. thanks for your help, https://flic.kr/p/UGkHkf – Jeremy Jun 20 '17 at 16:55
  • @Jeremy on the same label as the motor wiring diagram, to the left, there's a schematic. Please post a clear photo of that. – Tester101 Jun 20 '17 at 19:55
  • thanks link to new pic is below also noticed the blue wire is not attached to anything but under the thermostat it is attached to g. https://flic.kr/p/UKAVra – Jeremy Jun 20 '17 at 21:50
  • Thank you for you help, when connecting the c wire should I Just use the unused wire (orange) wire and connect it to the grey wire right? also since the red wire is already attached to the grey wire does that affect anything? Also I noticed the blue wire is not attached to anything but on the thermostat it is under G. Is that normal? Thank you so much for you time, – Jeremy Jun 21 '17 at 02:46
  • If you're going to use the orange wire as `C`, then yes, just connect it in with the grey and red wires. The red wire that's already connected to grey, is presumably going to the contactor of an A/C unit. So keep that connected as well. In the photo you've provided, it looks like the blue wire is attached to `B` on the thermostat, and the green wire is attached to `G`. However, it's difficult to see, since the wires are in the way. – Tester101 Jun 21 '17 at 10:47
  • Thanks, yup it is b.I took a quick look at the pic and made the mistake. I wonder why it is not attached to anything on the other side? I will be trying to install it today. Thanks for you help – Jeremy Jun 21 '17 at 16:58
  • @Jeremy `B` is used for the reversing valve on a heat pump. Since it doesn't seem that you have a heat pump, whoever installed the thermostat likely just connected the wires based on color (red to r, white to w, etc.). – Tester101 Jun 21 '17 at 21:49
  • ok thanks, I installed it and it is working. Thank you so much, – Jeremy Jun 22 '17 at 01:03
  • @Jeremy glad I could help – Tester101 Jun 22 '17 at 01:27