Unused Wire

[Moekhan82]

My old Honeywell had an unused in “U” but I don’t know where to put that in the new thermostat. I’m afraid of leaving it exposed.

 

[Ryan_G]

Hey Moekhan82,

Thanks for reaching out and we're sorry for the delay.

The Nest Thermostat doesn't have a terminal for "U". By looking at the photo, it looks like the rest of the wires are compatible with Nest thermostat and for us to further check, you could take a look at the main board of your HVAC and verify if the U wire is connected to somewhere.

Also, you could take a photo of your current wiring from the terminal for us to have a better view.

I hope to hear from you soon. 

Regards,

Ryan

[Apeluv]

Where’s the main board? 

[Ryan_G]

Hey Apeluv,

Thanks for being here in the Google Nest Community.

We're sorry for the delay here. The main board can be accessed through your HVAC. There's a control board to each HVAC unit and this is where all the wires go from the thermostat.

I hope it helps.

Best regards,

Ryan

[Ryan_G]

Hey Apeluv,

I just wanted to follow up and see if you're still in need of help. Please let us know as we would be happy to answer any questions you may have. 

Best regards,

Ryan