No cool air with Wyze Thermostat

I installed new Wyze thermostat in October of 2021 - worked fine. Now as summer is here there is no cool air… AC unit is running, only warm air coming out of vents.

Attached is picture of old wiring. I’m really hoping I can fix this and not have to purchase the old thermostat brand again.

Help please? Thanks very much in advance!

Furnace wiring pic:

I need a picture of the wiring at your furnace after you installed the C adapter, but from your wiring and description, I’m guessing that the black Y wire is no longer on the furnace board, and is instead on the C adapter?

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Hi speadie, thanks for quick reply. Please see pics of Wyze wiring and furnace wiring below:

Please note I performed installation without a C adapter (moved G wire to C on furnace end).

Right, that’s why you’ve got no cool air. G is required for the indoor fan to turn on when the air conditioner runs

Thanks speadie - then what would you recommend doing here without having to get a new thermostat? Should I switch from C to G on furnace side?

use the C adapter.

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Hi speadie, please see pic of c adapter:

Hey speadie, now that I installed the C adapter, the vents are not blowing any air now! I checked the ac unit outside and that is not even turning on so something with the new wiring is not getting that to run?

I’m not an expert but The wiring into C adapter looks ineffective… a lot of exposed copper. Should I rewire?

The only wire that should be connected to the Y terminal on the c adapter is the blue Y wire. The black Y wire needs to stay on the furnace board’s Y terminal

Ok, the black and blue wires were spooled together on old configuration - I took them apart but the black wire doesn’t have any copper out like the other wires:

Yes, that’s normal. The black Y wire is either stranded tinned copper or aluminum, but the black Y wire must be connected to the furnace board with the Y ribbon cable wire. The only wire you want connected to the Y terminal on the C adapter is the one that comes from the thermostat. The instructions that were on your phone when you set up the C adapter also tell you this. Which, if you didn’t reset your wyze thermostat when you installed the C adapter, you will need to do that. Make sure to tell it that the wires on your old thermostat are Rc, G, Y, and W, and it will walk you through the wiring of the c adapter.