installing my new nest thermostat

[dvsatech]

Installed my 3rd nest thermostat. 1st two not issues. The third one will not run fan or cool. I have a 4 wire system. I have Rc, G, C, and Y1. If I touch wire Rc to wire G the fan comes on, if I touch wire Y1 to wire Rc the A/C runs and cools. I connected all the wires  to the base and connected a nest. The nest powers up fine and I ran through the configuration but the test of the FAN and COOL does not work. I verified the wires go in far enough to keep tabs pressed and that the Y1, C, G and Rc are connected to the correct tabs. I tried a second nest and it did the same thing.

[dvsatech]

additional note: I replaced a previous digital thermostat that worked fine. I labeled each wire with the supplied tags before disconnecting.

[dvsatech]

So I returned the thermostats and ordered 2 new ones and they did the same thing??? I pulled another working nest from the 2nd floor and plugged into the new base and it worked. So I put the new nest into the old base and it wouldn't work so I started comparing things. The new nest has an older version of the software than the one working so I forced an update and now its working! 

[AxelD]

Hi dvsatech,

Thanks for posting in the community! Sorry to hear that your new Nest Thermostat wasn't running the fan and cooling. Thank you for reporting the issue and providing all the details. It's great to hear that forcing a software update resolved the problem.

If you experience any further issues with your Nest Thermostat, please let me know.

Regards,
Axel

[dvsatech]

I wish I had figured that out before returning (2) thermostats as not working when I probably could have made it work with a software update. I would think that the documentation would have suggested a software update especially when troubleshooting via nest.com/t01 and nest.com/t03 as checked both while troubleshooting.