Missing Y wire in wyze themostat no AC

Hello… i have changed to the wyze thermostat and installed the c wire adapter but unfortunately the app keep saying that im missing the Y1 wire although it is connected. so the ac won’t work when i put it in cool. Does anyone have a clue about this issue?

Welcome to the Community!

Can you provide photos of the furnace board with C Adapter and the Wyze backplate?


I noticed that the wires that come out of the furnace go to another small box then goes up to the thermostat.

You do not have A/C installed?

you have yellow wire wrapped around and is not connected to the terminal. strip and connect to furnace terminal.

since you already have C wire (looks like black at furnace) that is your C wire.

Green is G wire.

if they goes to another small box, go there and see what is in there. just in case, splices to different thing.

This is the small box

if I read it, too left wire goes to thermostat, lower right from furnace.

At the wyze the Green should go to G
where is the Black? that was connected to C in white box. Connect that to C.

your blue goes to O. (not sure your original if it goes to old thermostat.) obscured.

you do not need to touch yellow wire at furnace as it is not connected to board.

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