I’m having this issue as well. I have a G wire at the thermostat and no C wire, but I have a C wire on the furnace equipment panel. Wyze instructions said to label the G wire as C and connect to C on the thermostat, but both systems are turning on when selecting heat. Did you have a C wire on your furnance? I’m thinking I need to connect the C wire on the furnace equipment to the Y terminal on the Wyze adapter.
Curious if OP just changed the wires at the thermostat or also on the equipment.
Exact same issue and setup here. Y wire from original thermostat went to the compressor. A wire comes back from the compressor and goes to C on the furnace panel. Nothing was connected on the furnace control at the y post. I installed the C adapter. The Wyze thermostat only powers up if all of the adapter wires are connected including the Y wire from the C adapter to the Y post of the furnace control. During test, the heat mode turns both the heater (gas/forced air) and the A/C. The compressor makes an awful noise. When switched to cool mode, the compressor and fan run normally and heat appears to be off (although I didn’t leave it on long enough to tell for sure). On the C adapter I inserted the Y wire from the thermostat and the one going out to the compressor. Then tried it with the Y wire coming from the thermostat going directly to the compressor as it was before. This meant there was no Y wire plugged into the adapter Y out. Same result, AC comes on in heat mode with loud compressor.
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I was able to get both to stop turning on by disconnecting the C-wire on the furnace and connecting it to the Y-terminal on the Wyze adapter, however now cooling mode doesn’t turn on the compressor. I suspect I may need to connect the Y-wire on the Wyze adapter to the C-terminal on the furnace, being that Y was not used previously.
I have the same setup of wires and I’ve added the c-wire adapter but all that I get is a clicking at the thermostat - it never displays the WYZE logo
Has anyone encountered this problem yet?
Thats what I did. Following to see what wyze says.
do you have a picture of the wiring on the furnace before you changed anything? where do those blue and yellow wires go that are on the thermostat wire?
A lot of problems here could be avoided by people just using extra wires for the C terminal. if you have unused wires in your thermostat run, use one of them for common, don’t mess around with the adapter unless you absolutely need it.
Also, the adapter will not work unless you have 4 wires that are directly connected to the thermostat connected to its terminals. if those wires pass through something else on their way to the thermostat, they will not work, because when the wyze uses that wire to power itself, it will also turn on the device that is in series with it.
If you have a Y wire that goes from the outdoor unit directly to the thermostat and does not go to your air handler/furnace, then you will need to fix that by running the Y and thermostat wires back from the outside unit to the air handler. Hopefully, you have some spare wires in that run.
Thanks to comments here and elsewhere on the forum I was able to figure it out. What wasn’t clearly stated or shown in any diagrams was how it should look with the C adapter in place. Since the original Y Wire from my old thermostat was going directly to the AC compressor and not to the air handler, I had to split that connection and connect the wire that goes to the AC compressor directly to the air handler as @speadie mentioned. Then put the Y wire coming from the thermostat to the Y port of the C adapter. I’ve attached a diagram showing the new wiring configuration. I reset the thermostat by pushing the button for 5 seconds and went through all the setup steps again. It’s working perfectly now.
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Hi speadie
Thanks for your time on this. My original setup was four wires at the Tstat but five in the furnace without the blue hooked up. So I just reran the 18/5 from the Tstat location and rewired. Flipped the switch and I was in business. Thanks again for all your effort with this!
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@RabidMitch and @speadie, thank you for your help. I have resolved my issue. My Y wire coming from the thermostat was split before the control board to a wire running to the ac condenser. I rewired the system so that the Y wire had a continuous connection to the control board. From the control board, I now have two Y wires, one from the C adapter and one going to the condenser. Basically the split to the condenser needed to happen at the control board and not before it.
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