I have the same setup and my NEST runs just fine. The battery charges while it’s calling for heat.
I’ve had my 2nd gen for over a year now. It’s a nice thermostat, but I bought mine at a good discount, and I’m glad I didn’t pay full price.
It does what it’s supposed to do rather well, but the functionality really depends on a number of other factors. Most notable is what gotpasswords had to say. My thermostat is in an area that we don’t frequent, and so the auto-away serves no real purpose. The learning behavior seemed to work reasonably well, but if you have an erratic schedule and/or a family with different comfort levels, it might also defeat this feature.
Besides the activity tracking, the fact that it looks cool, and some other nerdy bits, it also keeps local weather details and I mostly enjoy the remote functionality. I wouldn’t say it’s a must-have device, but it’s definitely better than the very old Honeywell it replaced.
The Honeywell WiFi I bought doesn’t have a battery option, it must get constant AC power from something (normally a separate power wire in the thermostat circuit, which mine doesn’t have). What I meant was a couple of AA batteries like in an old programmable thermostat wouldn’t work, they’d go dead fairly quickly powering the WiFi. I guess the NEST has a rechargeable battery pack that can be charged by only the small amount of current flowing thru the thermostat circuit when it’s closed (though I wouldn’t have thought that would be enough). How does it stay charged enough in the summer when the heat rarely turns on?
Something else with my thermostat at least: Your smartphone does not communicate with the thermostat directly*****. Once it’s setup your smartphone’s app goes thru your router to the internet, tells Honeywell’s servers to change the temp, their servers then send that message thru the internet back to your router, and your router sends it wirelessly to the thermostat. So it doesn’t matter if you’re right next to the thermostat or on the other side of the Earth, it always uses the internet.
*****Actually the phone does connect to the thermostat directly thru WiFi during setup, you access the thermostat’s settings this way once to program in your router’s SSID and WEP key. After that both the phone and the thermostat only talk to the Honeywell servers via the internet. This is what I meant by it being a little tricky to initially setup.
As a matter of fact, after I read and responded to your last post I thought to myself, “I wonder if my NEST is going to start after having no power for 6 months”.
I may have gotten how it works backwards, now that I think about it. It might use a trickle of power for use and battery charging EXCEPT when it’s calling for heat (then it uses battery for its display and wifi and such). I think I remember reading that this doesn’t actually work for everyone with a 2 wire system, just luckily works fine for me.
I honestly don’t remember, but I keep the whole circuit my boiler is on turned off during warm months so one way or another it hasn’t gotten any power for a long time. I guess i’ll find out in another month or so.