Trying to upgrade an old thermostat to nest, I have the following wires, yellow, white, red and blue.. in many videos he 4th wire is green.. I'm confused as to where this blue wire goes..
Correction, I have the green wire but don't have the yellow
Are the terminals on the old thermostat not labelled? Usually you just have to match the old letters to the Nest letters.
Post a picture of the original thermostat's wiring here
I just wanted to follow up and see if you're still in need of help? Please let me know, as I would be happy to answer any questions you may have.
Thanks for your help, Patrick_Caezza.
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