Wiring Compatibility

[WillJohnson]

On my HVAC system I have a single red wire coming in and on my old thermostat it goes in to the Rh terminal.  There is a jumper between the Rh terminal and the Rc terminal.  Since I only have one red wire coming in from my system I am assuming I don't have a dual transformer system. So shouldn't I be able to connect the single red wire coming from the system to the R terminal on the Nest thermostat? 

 

[Patrick_Caezza · Accepted solution]

You are correct.

White - W to W

Red - RH to R (jumper not needed)

Green - G to G

Yellow - Y to Y

There is a very good chance you will need to add a C wire. If there is a spare wire hidden behind the thermostat you can use that or you can use the Google Nest Power Connector to create one

[WillJohnson]

Thanks Patrick!! I did have an extra wire that was not connected to the old thermostat that I was able to connect to the C terminal!! So far working like a charm!

[MelbaDT]

Hey folks, 

As always, thanks Patrick_Caezza for the detailed wiring guide. 

WillJohnson, I'm glad to hear that you've got everything sorted out. Feel free to let us know if you have further questions. 

Cheers, 

Melba

[MelbaDT]

Hi, 

I haven't heard from you in a while so I'll be locking this thread if there is no update within the day. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community.

Best, 

Melba