I have two stage heat, no air conditioning.
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Yellow is stage 2 (W2) wired as shown , thermostat does not light up, no action at all. Help?
Would you happen to have a picture of the connections on the Wyze thermostat, and possibly also the connections on the control board on the furnace or air handler side?
when u say the tstat doesn’t light up, are u saying it doesn’t power up? if so, def post pix of the wyze tstat wiring & furnace wiring
Ken:
Thanks for the response, picture of Wyze wiring attached. The yellow is stage 2 of my heat. You are correct, there is no sign of life from the tstat.
Regards,
John
Wyze gets its power from Rc and C. The red wire that you currently have connected to Rh needs to go to Rc. That should fix it 
Vincent:
I will try it again, but at one point I was on Rc, I moved it as a result of no power.
Regards,
John
use a multimeter and check for AC volt between red wire and blue wire.
take a pic at your furnace connection terminal.
Did your old thermostat work without batteries? If it did, then there must have been power between Rc/Rh (those are usually jumpered together) and C. If you needed batteries to power the old thermostat then the C wire might be broken if that is connected both at the thermometer and furnace terminals.
Vincent:
I went and took the cover off the furnace, and remembered that my HVAC buddy told me I didn’t need the blue wire because the Honeywell had batteries. What I discovered today, is that he unhooked it. I reconnected it to ground, and now I have voltage between it and the red. I will attempt to reinstall the Wyze this evening, thanks so much!
Regards,
John
Wait, when you say “reconnected it to ground”, do you mean to say that you reconnected the C wire to the C terminal? Just making sure because “ground” and “common” aren’t necessarily the same thing. It needs to be connected to the C.
And yes, that makes sense. When I bought my house 10 years ago, my thermostat only worked on batteries. Fortunately, when the Wyze thermostat got here, there was an unconnected wire already between the wall and the furnace, so I could just connect the wire and I was up and running
Chassis ground and 24v common are generally the same thing in a furnace, but you’re right, he should still make sure it’s connected to the common terminal, just in case.