Google Nest Turned Off

[mkeysaer]

I installed my Nest thermostat last winter.  It has been working fine.  During the summer I switched it to Heat + Cool.  I use this for a vacation home, so I am not there most of the time.  I noticed at the beginning of fall, the temperature in the house was dropping into the 50's at night.  I don't know if this is part of the Eco settings.  I was last at my house November 1st and received an alert today (November 20) from the Nest that the house temperature had dropped below range.  The temperature in the house was 39.  I wasn't monitoring the temperature and looking at the Nest energy report realized the heat has not turned on since my last visit.  I switched the thermostat from Heat+Cool to Heat only and the furnace immediately switched on.  Switching back to Heat+Cool it remained on, but I am now keeping at Heat only.  Why did this happen?  I am now concerned about the reliability of the thermostat as temperatures continue to drop into the winter.

[RenzJ]

Hi mkeysaer,

Thanks for bringing this up here in the Google Nest community. I'd be happy to take a look at this for you. This doesn’t normally happen, but based on your description, sometimes the HVAC does not turn on. We need more information for us to be able to determine a permanent solution. Please answer the following:

1. What is the make and model of your furnace?
2. Send us a photo of your current Nest Thermostat wiring.
3. Do you have a multimeter?
4. Gather power readings. Follow the steps below:

For the Nest Learning Thermostat and Nest Thermostat E:

1. Press the thermostat ring to bring up the Quick View menu.
2. Turn the ring to Settings and press to select.
3. Turn the ring to Technical Info and press to select.

For the Nest Thermostat 2020:

1. Tap the touch bar to bring up the Menu view.
2. Slide your finger down to Settings, then tap to select.
3. Slide your finger to Equipment > Power Info.

I look forward to your response.

Best, 

Renz