Have not experienced consistent warm-up time periods. At times the warm-up will begin over an hour before the programed start time. Other times it doesn't begin heating until right at the selected start time.
I only got this thermostat because I had to get a new furnace. The business insisted that I had to take a thermostat as part of the package so I reluctantly agreed. I don’t like it at all. It’s huge and has very few of the features that I prefer. I removed it right away and put my original thermostat back in. Oh, I will use it again. It’s going with the house when I sell it.
Nice unit with only one issue. Cools behond set temperature. I.e. set to 79, unit continues to cool to 77 before a/c fan & compressor shuts off. Does same at all temperatures set
Nest is a much simpler, user friendly thermostat. Easier to program remotely and in person. Better looking. I only have this thermostat because the builder installed it.