Installing Wyze Thermostat No Circuit Board

Continuing the discussion from Installing the Wyze Thermostat with no circuit board:

Hello. My HVAC unit is 2016 but there is no circuit board. I have been reading several post on how to connect it, and I saw some diagrams from @speadie which I believe worked but I find that my unit has a slow switch and I’m not sure how to wire this correctly.

The thermostat had the standard 4 wires connected G Y W R (plus bridge to Rc) and there is a blue wire available not being used.

Please see pictures. Help! :frowning_face:

Adding more pictures for further reference:

Adding more pictures for further reference:

Adding more pictures for further reference:

Adding more pictures for further reference:

I see a blue wire hiding in here behind the thermostat:
image
Take that blue wire, strip the end and add it to the C terminal on the Wyze.

Then, at your furnace, take this blue wire
image
and strip a bit off the end and add it to this wire nut:
image

Wiring it in this way will allow the wyze to continue running even then the ac compressor is locked out due to a bad float switch, and it will still prevent the compressor from running if you have a clogged drain line - If, instead you wanted the thermostat to turn off if the float switch gets stuck or the drain line becomes clogged, you would wire that blue wire to this wirenut instead:
image

Either way, tell wyze that your “old thermostat” has the following wires during setup: Rc, C, Y, G, W
And make sure you tell it your heat source is electric when it asks.

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Thank you so much @speadie !!