Wyze thermostat C adapter wiring help needed

Hi,

Tried installing the Wyze thermostat today and had to stop due to the wiring at the heating air-conditioning system. I’m coming from a Nest Gen 1 and only have Rh, G, Y1, and W1 wires connected at the thermostat. I didn’t know that I needed to use the C adapter before purchase. This should be clear on the product webpage. In either case, here’s the problem. At the HVAC system, there’s a black wire connected to the C terminal and the Y terminal has a yellow and red wire connected. How do I wire this up correctly?

Note, the G and W terminals only have one wire as expected. Lastly, I have a blue wire not connected at the thermostat and the C terminal at the control board. Can I just connect the blue wire on the control board which also has a black wire connected and then connect the blue wire to the thermostat?

Please help,

George

Just connect the blue wire to C on both the wyze and the furnace. Leave all other wires where they are, C will have 2 wires on it, and that is fine, The the black and red wire go to your outdoor A/C compressor to tell it to turn on when the thermostat calls for cooling.

Hi,

I did that and the thermostat displayed WYZE, but I’m getting an extra wire error. It tells me to turn off the system then remove the wires. I only have 5 wires and the ones the app shows as extra I don’t have. Any ideas? I can’t get past the “extra wire” error message.

As a side note, my previous thermostat red wire was connected to Rh and the Wyze app wants me to connect it to Rc instead. Does that sound reasonable?

Thanks again,

George

Yes, Rc is the wire wyze uses for all power unless you have a split transformer system. I’ve heard of the extra wire problem from other people, my theory is that it is being caused by interference and possible noise from some people’s transformers. You should be able to keep trying and it will allow you to skip the error eventually, but some people are not able to get to that screen. I’m not aware of any other workaround other than to keep trying again until it lets you skip the error unfortunately.