I tried to use the online compatibility help but am unable to get a definitive answer. The conclusion is that my system might be compatible with Google nest. Could someone help? The letters are G, W , Not used, Y, R , Rc (from left to right). Also I have a blue color wire connected to “not used”. If Google nest is compatible then where should the blue wire currently connected to “not used” be connected to for Nest?
Looks like a basic Heat and AC system.
The blue should be C common wire but you will have to go to the indoor unit and look if the blue wire is actually connected to the C terminal on the furnace. If not you will connect it to the screw terminal marked C aka common on the furnace.
Then the wires on the Nest are all the same as the old thermostat except you do not use a jumper on any connections on the Nest just put Red to Rc, Blue to C, and the rest of the wires to W Y G.
You have to tell it if you have Gas heat or oil or electric heat and if it is ductwork forced air not a boiler with radiators or baseboard heaters.
I assume you have forced air gas heat but you did not say what kind of system you have.
Hi I am still looking for clarification on my furnace compatibility to the Nest. I have Trane forced heat and central A/c system. Gas heat via ductwork. So my next step to see if the nest can be changed out with my current Honeywell thermostat is to look for the blue wire connection in the furnace control board? Can you clarify if my next step is to go to the furnace control board to see If the blue wire is actually connected to the C terminal on the furnace. If it is, what do I do? If it is not, @Houptee mentioned that I will connect it to the screw terminal marked C aka common on the furnace. I need clarification on what "it" means? The blue wire in the furnace control board or the blue wire in the Honeywell thermonstat?
When you install the Nest you need a C wire so first go look at the furnace and take a pic of the terminal screws where the thermostat wires are connected. One should say C and the blue has to be connected there. Some brands call it B instead of C on the furnace.
Then when you are installing the Nest the blue will go to C on the Nest and the rest of the wires just match them up to the Nest.
I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any concerns or questions from here, as I would be happy to take a closer look and assist you further.
Thanks for lending a hand, Mark, Houptee and Mel.
Just one quick final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, I would be happy to keep it open. If there's more we can do, just let me know.