Nest 2nd Gen Heat Pump Compressor wont go on

[ericknope]

Hi,  I replaced my Honeywell with a Nest 2nd Gen learning thermostat.  The heat only works with Auxiliary Heating.  With regular heating, the outside compressor doesn't come on and the vents blow cold.  I reinstalled the old Honeywell and everything works fine.  I shorted the yellow wire to the red one and the compressor comes on.  I tried my already working 2nd Gen Nest onto this base and i get the same thing.  I have included pics of my before and after wiring.  Just wondering if there is a work around for this or if I'm doing something wrong.

Thanks in advance, Eric

https://photos.app.goo.gl/cPB8QK5wH2inawXx6
https://photos.app.goo.gl/gi1svRjHTtSpGAGV6

[Jenn4T]

Interesting.  I’m having the same issue.  Outdoor unit periodically won’t activate with my heatpump system.  HVAC tec has tested and retested unit.  Claims he can find no reason for this and is blaming my Nests.  The only thing that works for me is hitting the breaker, letting everything reset, and turning everything back on.  I’m subscribing to see if anyone contributes to your post and I have posted recently, as well.  Good luck!  

[ericknope]

Yep, sounds like what mine is doing.  I'll update this thread if i make any progress or my tech says something different.

Eric

[Cjacobs129]

I’m having about the same problem. I think it’s in the temperature balance settings. It cuts out the outside unit when the temperature falls below a certain temperature. https://support.google.com/googlenest/answer/9248719?hl=en#zippy=%2Cchange-heat-pump-balance-setting...

heres a link to instructions.