Extra black Aux wire

[ZMcclurg10]

Hello everyone!

I just installed my new nest thermostat on my new house, I have a black wire that was plugged into an Aux location on the previous thermostat. 

The other wires I have are:

W, a blue wire that was marked B/C, Y1, orange Y2, G, R, and the extra black Aux wire not current in a port.

I checked my system, the manual says it's a "upflow/horizonal and down flow gas-fired direct/non-direct vent, 2 stage condensing variable speed furnace". So far it seems the A/C is working as it should, but I'm concerned that this black wire was something that's going to prevent the heating from working correctly when it gets cold. Any help is appreciated!

[ZMcclurg10]

Hi all, wanted to follow up with pictures of both my nest wiring and furnace wiring bus.

 

 

[Ryan_G]

Hi ZMcclurg10,

Thanks for reaching out here in the Google Nest Community.

As I checked the wiring from the main terminal, it looks like you have a heat pump but I couldn't verify if it is a second stage heating or cooling. With the presence of the black wire, as you mentioned it is for AUX, your system might be more compatible with the Nest Learning Thermostat. You could use the OB terminal for your orange wire and the AUX terminal for the black wire.

Check out this link to know more details.

Regards,

Ryan

[Ryan_G]

Hey folks,

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
 

[Jeff]

Hi everyone,

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.

Thanks,
Jeff