looks good. just remember that the green wire at the thermostat is connected to “C”
Hello to all the experts and helpful community members,
I’m installing a thermostat for the first time, and the limited instructions are making wiring tricky. My thermostat has 5 wires connected to Y, R, G, O/B, and W. The HVAC has connections for G, Comm, W, Y, and R. Interestingly, the wire colors don’t match between the thermostat and HVAC. I noticed the common wire on the HVAC is white and connected to O/B on the thermostat.
Do I need to change any wiring on the HVAC? If not, which wires should I connect to the Wyze thermostat?
The wires at the thermostat are very dirty and it is hard to see the colors of them,. Also, you probably have a splice somewhere in the wiring near the furnace. can you follow the brown thermostat wire from the furnace and see if you can find the splice?
Apologies for the picture with dirty wiring but I cleaned it up and here is what is shows on my current thermostat :
Orange wire going to O/B
White going into W
Green wire going to G
Black going to Y
Red going to R
However when I checked on HVAC wiring, the orange one is not connected anywhere and is tied around the brown cable wire.
Do you know if your air conditioner is a heat pump? if it isn’t, and that orange wire isn’t going anywhere else along the way, you could use it as your C wire.
If you share the model number on your air conditioner compressor outside, I can look it up and determine if it is a heat pump model or not.
Thanks for all your help! The furnace model is 58MCB060 and air conditioner is TCGD18S41S3A
That’s not a heat pump, so with the power off to your furnace you should be able to simply connect the orange wire at the furnace to C (leaving the white wire currently on C there so that your C terminal now has an orange and a white wire connected to it) and connect the orange wire to C on your wyze, telling the app that your old thermostat has the following wires:
W, G, Y, R, C
I have an old train unit, and I can’t figure out where the C-wire should connect. See the photo. The thermostat wiring bundle is located at the bottom center-right, while the outside unit power supply wire bundle is on the left. Additionally, there’s a dark blue-striped wire on the far right that comes from the thermostat, which I would like to use as the C-wire. Thank you for your help with this.
@speadie Yes, that was it. The thermostat is working now. Thank you so much!