Wyze thermostat voltage issue

So I’m trying to install the new thermostat, I got it all wired up correctly but as I connect the R wire to the C blue wire I’m getting 15-16 volts. I read that you need at least 24 to make sure it powers on. All the other wires read up to 26 volts or so. Cant seem to figure it out. I have not checked the Furnace connections since it’s nighttime and it’s on top of my roof. Have you guys tried using jumpers to get it to the correct voltage?

So I added a jumper cable from Y1 to C to regulate the voltage. It seems like it worked. I will try to access the controller in the furnace tomorrow and update on my findings.

I think I am having a similar issue. I connected the C-wire (Blue) to the Red wire and it worked for the installation, but then it asked for a firmware update and it turned off. It doesn’t want to turn back on or factory reset. I guess it may no be enough voltage? Not sure

Sounds good. If it works could you show us the jumper cables you used?

Post pic old thermostat wiring. And new wiring pic

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So I don’t have my Wyze thermo final right now because I forgot t ok take one and quickly installed my old Honeywell back after it stopped working. Although all the 5 wires were connected. After it failed I tried several combination, I put the R wire to both the RC then RH section. I put the G in the C section with out the C-wire. I also disconnected the G wire and left the other 4 like the app suggested for some reason.

My C-wire wasn’t connected to anything and my Honeywell wasn’t using it. My control panel doesn’t use screws to connect it and uses some sort of clips (I added a pic. The control panel is behind all the wires, I know it’s not as clear) All the wires needed are on the outside of the furnace and connected with Wire nuts like in the last or 4th pic. I looked up a solution and found that I can connect the C-wire to the R wire. (How to Connect an Unused C Wire (Common Wire) - YouTube) the video explains it.

The Thick C-wire that was connected to the R wire and I connected the Thin C-wire to it. It’s the 2 wire Nut combination in the last or 4th picture. That gave the thermostat power for 5 mins. It asked to update the firmware and it crashed and won’t power back on. It may bot be receiving enough power or idk

your c wire is connected in your unit it is common.

This is your wiring.
wyze thermostat terminals.
Rc = Red
Y1 = Yellow
G = Green
W1 = White
C = Blue

Tell the app you have those letters.

push the button on the thermostat for 15 seconds to factory reset and start over.

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you should not be jumping colored wires at the stat.

I tried that, but the Wyze Thermostat is not powering anymore. It won’t reset. Idk if it’s getting enough voltage or if it’s another issue

I moved the RC to RH and G to C on the thermostat based on what I saw on the other forums about how other people got there’s to work

did you use the add a wire white puck thing… your system does not need it.

do you have any kind of volt meter. you could check between red and blue for 24 vac

I would also check the blue wires at the unit. take the wirenut off and check to make sure all wires are connected. in your picture it was light blue, blue and red.

What white wire puck?

I just got a multimeter and it’s giving me reading about 27-29 volts the wires. So I’m not sure what else I can do.

I just plug in the Wyze Stat and it’s not powering up and I cant reset it. I checked the voltage while it’s attached to the wall and it’s showing 27 consistently. So idk why the Wyze stat won’t power now

Hey there,

Can you show us how you wired the Wyze thermostat?

Craig shared the correct wiring.

At the minimum you need your R wire connected to RC and your C to be connected to have power. The. Of course your Y and W and G connected to is right terminals.



So that’s a picture of another persons set up. I live with Roomate’s and I switch back to the old thermostat quickly and forget to take a pic, although that’s how I has it set up when it worked for 5 mins.

In the wiring picture, I labeled the lug nuts 1-5.

  1. Has the W - white and a brown one that I’m not sure we’re it leads too.
  2. G- green
  3. RC? - red
  4. C - thin blue, C thick blue, and second Red? That’s also coming from the Y wire line(controls AC I think)
  5. Y- yellow and second red wire that’s connecting to the 4th lug nut.

Hey there,

It looks like you have An 18/ 5 wire and an 18/2 wire. Wondering where the 18/2 wire is going maybe to another transformer??

If you have a multimeter you should check your wires at the Wyze terminal board

The thermostat uses Rc as the main power leg of the 24 v transformer.
Then the thermostat utilizes C to close the loop for powering the thermostat.

When the thermostat asks for heat to be on it connects RC and the W1 and it turns on.

When the thermostat asked for a/c it connects RC and Y1 and it turns on.

When it needs the fan on obviously for both heat and a/c it connects RC to Green.

So you need to make sure you have 24 volts from RC to all of the other terminals I just mentioned.

If RC and C does not have at least 24v then it’s possible you ha ve either a wiring issue or maybe another power supply somewhere that is crossing.

Take the wires out of the Wyze terminal carefully and check power to accurately check.

I checked with a Multimeter already. It had 27 volt. So I’m not sure why it’s not powering it up. Could the the firmware update mess anything up? Because it was working then it stop during the firmware update.