Upgrading Nest Learning Thermostat from gen 1

[Bodam2005]

I currently have a gen 1 thermostat. I am upgrading to a gen 4. Is there a recommended upgrade process? I'm not asking about physically replacing the device.  As an example, do I delete the old one from home and nest before I replace it or after?

[David_K]

I'd recommend factory resetting and removing your existing thermostat from the app first.

Restart or reset a Nest thermostat - Google Nest Help