AC is running in Heat mode

[Stifflerstan]

I've recently switched over too a nest thermostat in around June. Which during that time I never had too run the heat. Now that the temperatures are dropping I've found my thermostat says it's heating but it's turning on my outside unit and cooling. I'm assuming it's a wiring issue maybe. Any help thank you

[Stifflerstan]

 This is my current wiring setup. 

[Houptee]

Is this a gas furnace and A/c, or is it a heat pump?

[Plewando1955]

I’m having the same problem with my nest. I have a forced air furnace and have reinstalled the nest twice and it still turns on the AC unit when it needs to heat. If I turn it over to emergency heat the furnace turns on but not the AC but none of the schedules. 

[Stifflerstan]

I figured mine out. Somehow it was setup with a heat pump. Make sure too select the appropriate settings when installing. I had my furnace selected on electric instead of gas and this fixed my issue. Hope it helps

[Houptee]

You have a heat pump system or a gas furnace with a/c?

If you have a OB wire it must be a heat pump system.

You can change the setting of what the OB wire does, some systems need to have + power when it asks for heat and some need the opposite so you change that setting in Nest menu and see if heat comes on.

[Stifflerstan]

I have gas. No OB wire. 

[Jake]

Hey all,

Sorry for the late reply. I wanted to follow up and see I could be of any help. I found an article that has some troubleshooting steps that could resolve the issue. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further. 

Best regards,
Jake

[EdwardT]

Hi folks,

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 trouble from here, as I would be happy to take a closer look and assist you further.

Thanks,

Edward

[aatienza]

Hey there,

Just checking in to make sure that you've seen our responses. Please let me know if you have other questions or concerns as I will be locking this in 24 hours if I won't hear back from you again. Feel free to start a new thread and we'll be happy to help.
 

Thanks,

Archie