I need help with the C-wire adapter setup. I have two Carrier 58STA/STX HVAC systems in my attic for the home. The control board wiring seems a little complicated. I see two wires going into Y/Y1 terminal. Also, I see two different RED wires. I am attaching the picture of the HVAC control board. Please assist.
Actually looks pretty straightforward. It appears the white white wire on Y & the red wire on C is a different cable going to the condenser. The yellow wire on Y is most likely going to the thermostat. Trace those wires to verify 2 different cables. If they are as I described, check the thermostat cable for a extra wire not being used. If there are no extra wires, you’ll need to use the C wire adapter from the Wyze thermostat. That C wire will connect to the C terminal (labeled com 24v) along with that existing red wire.
Edit… Now that I look at your picture better, there is 2 different cables, the white & red wires I spoke about are most likely going to the condenser.
It appears there is a blue wire that may not be used on the thermostat cable. Verify its not being used. If it’s not, verify at the thermostat, that the blue wire is also available. If available, connect that blue wire to the com 24v terminal on the control board and connect it to the C terminal on the Wyze thermostat. You won’t need the adapter.
Hi Ken - Thank you for the tip. The blue wire on the thermostat has been cut short. I don’t think I will be able to use it. Any other tips to make this thing work? Thank you!
It looks like it’s wrapped around the cable, straighten it out and see how long it is
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The wire set that is only the red and white - that goes to your outside condenser unit. Those are not the ones you need to be concerned with though they do need to stay on those same terminals (red to C, white to Y). The ones you need are the white, yellow, red, and green ones. Blue isn’t used in the bundle. Those four will go to the back of the adapter. Then from the adapter flat cable, wire all appropriate for where you removed the original wires. They are labeled on each wire (even though they are all physically white). Then the C wire from the flat cable will connect to that Com terminal (the middle red wire).
If anybody sees issue to this, please chime in. I just installed mine two days ago.
Ignore my previous message. Re-read the whole thing again and was able to get it work. Thank you all for your help!