Nest update issue

[Free628]

I bought a new house last year with 2 furnaces working upstairs and downstairs I installed my gen 2 nest thermostat and bought a newer gen 3. They worked all winter and through this summer without issues. I switched my thermostats over to heat this week with the winter looming near and my gen 3 began to show the red screen and the temp but would not kick on my heat... I thought this to be odd as it had worked before and no wiring had changed. I then placed my other gen 2 on the base to see if it worked... Like clockwork the furnace kicked on and began blowing heat. I then took the non working gen 3 to my other base and it still did not work, however my gen 2 when placed on the base fired the system right up. I assumed at this point that my gen 3 had gone bad 😞. So I ran to the store to buy a new one. I changed the base just in case and installed the new gen 3 and still no heat being turned on. I tried once more placing my gen 2 on the base and it worked just fine turning on the heat. I noticed both gen 3s had been updated yet my gen 2 had not been. I called customer care which proved fruitless as the agent couldn't understand what I was saying yet I ran through the troubleshooting steps with swapping the y wire and the w wire and then replacing the thermostat where if cool was selected the heat would come on and when heat was selected cool would come on. At this point the agent had no idea and wanted me to schedule to have a nest pro come out. I'm ticked as the wiring has not changed to these normally working units the only thing that has happened is an update and I am not paying 99.00 to have someone come out and tell me what i already know. So at this point does anyone have an answer on how to fix this or should this loyal google user just switch to another brand?

[Ashepherdson]

I have escalated this for you, but from the sounds of it there may be an incompatibility with the third gen thermostat since the second gen works and both your old third and new third gen both don't. 

[Free628]

The gen 3 thermostat worked last winter without issue... Nothing with the system has changed.

[Ashepherdson]

But as you pointed out there was a system update that may have created the incompatibility, I don't mean to say it's permanent of course, just that if does exist for the moment.  That's why I've escalated it , so that someone from the Google team can take a closer look for you 🙂

[Hug3kids]

I have had the exact same issue.  System worked fine last winter and all summer (with A/C).  Switched to heat last week and does not call for heat anymore.  I jumped Rh to W and the heat comes on, proving that the wiring is still working.  Voltage at the furnace controls across Rh & W are the same as at the thermostat as well.  I have read numerous other complaints of the same "no heat" issue.  Where can we find out if an update was performed and how can we roll back to an older version to see if that fixes the problem ?

[Free628]

I got mine too work! I factory reset twice and it now is currently working.

[Hug3kids]

Have reset 3 times and still no joy.  Still showing power across Rh & W when I check with a meter and still calls for heat when I put a jumper between the 2.

[Dsmit]

There was a firmware update last week (version 6.2-22) that seems to have triggered a number of issues for people. 

My gen3 thermostat has connectivity issues, but other models are fine.  

What firmware version are you running?

[Free628]

I am running that same firmware update.

[Hug3kids]

Interesting.  I'm currently at 6.1.1-21

My model indicates: Display 3.4 and backplate 5.4