Wyze thermostat only heat or a/C, not both

I need help figuring out the proper wiring from a Honeywell thermostat to Wyze. I can only get the heat running but not A/C and vice versa.

I have a black wire that I’m unsure of where to place on Wyze…there is not an option in the app for it. It used to be connected to K on the Honeywell thermostat.

Below is an image of the original Honeywell setup.

The Wyze setup I’m using is:
R - RC
B - Y1
W - W1
G - C

I’m using the Wyze C adapter too, with black in Y, W/W, R/R, G/G. The five C adapter wires are connected to the furnace panel to the corresponding colour letters.

Please help. I feel there is a simple fix here.

Looks like you posted a picture of the Wyze Thermostat. Can you post a picture of the Honeywell Thermostat Wiring?

Can you also provide a pic of the C Adapter connections and the Furnace connections?

… is there a reason you’ve got black in o/b, and nothing connected to W1?

I’m not at the home I installed it at, but the C wire adapter is connected to the furnace board according to the letters on the five wires. I.E, G-G, R-R, C-C, etc. Please let me know if more info here would be helpful.

Here is a picture of the original Honeywell thermostat.

Sorry, looks like I posted the wrong picture.

Here is the set up where I get the heat working but not the A/C.

When I switch the black and white wires between Y1 and W1, I get A/C but not heat.

So, the black K wire is like the Y wire, but you have a honeywell wire splitter installed on the other end of it (in the furnace, or ac unit, or air handler). you’ll need to remove that and use the C adapter that came with the wyze. if you show a picture of the furnace side of the wires, i can probably help you with how to wire it,

Thanks for your help!

Attached is a picture of the wire saver outside of the furnace and another one showing how it was connected to the furnace. If it’s hard to see, here are the details of the wire saver into furnace board:

Red, R
White, C
Green, G
Orange, Y
Black, capped with other black wire from thermo wires

I had removed the wire saver and used the Cwire adapter before posting this issue.

As a new user, I can only post one image at a time. Here is the image of the Honeywell wire saver.

So, when you connected the wyze C adapter, what wires did you leave on the furnace board?
There should have been a C and Y wire that did not go to the wire saver, and instead went to your air conditioner.
Those wires need to stay on the furnace.
Can you share a picture of the Wyze C adapter installed?

I won’t be back to the house until next weekend. I will send a pic then.

I believe the A/C wires were black to Y and white to C. There was also a thick black wire in C.

Based on this, would you be able to tell me the proper wire set up before I send the pic? I can try it and if it works it will save me another 1hr drive. If not, I understand that you need images to provide the right instructions.

The only wires that are connected to the C adapter terminal strip should be the other ends of the wires that are connected to the thermostat.

I’m zoomed in on your furnace board image, and it looks like you might have 3 things connected to C (2 whites thermostat style wires and a large black lamp cord style wire), and 2 things connected to R ( 2 red wires coming from opposing directions). Do you have an air cleaner or similar device? It needs to stay on the furnace board too.

In addition, you will want to reset your wyze thermostat and re-install it, telling it that your old thermostat uses the following wires: Rc, W1, Y1, G

It’s working perfectly now that I reset the system and app. Thanks a lot for your expert support!

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