We had an older Nest Learner thermostat, got a new furnace and a new thermostat, and cannot get it to work.
We installed our new Nest Learning thermostat, I followed the directions for set-up and got the message on the Nest app on my phone that I was all set. At this point, the Nest app began spinning and I could not get out of it. The furnace kept heating until the house was getting close to 80 and we shut it off by the emergency switch.
Sorry to hear about the trouble. I wanted to follow up and see if I could be of any help. I found an article that has some troubleshootings steps that could 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.