Nest thermostat not powering on and unable to reach google nest support

[rrlafo]

We recently bought a Nest thermostat, installed it and it was working fine. Then we decided to add a trim plate and now can’t get the Nest to receive power. We’ve tried all the troubleshooting suggestions but nothing works. I tried to get a call back from a Nest pro but when the call comes in and I’m told to press one I do, and it is not recognized so I lose the call. This happened several times . Then I tried the chat function but it kept telling me I wasn’t filling out the boxes correctly even though I was. How can I get help with this?

[CoolingWizard]

@rrlafo ,

If your statements are accurate, that is it was working fine and then you decided to add a trim plate, the problem was introduced when you disconnected the wires, removed the backplate, mounted the trim plate, added the backplate, reattached the wires, attached the display.  

You need to use a Volt Ohm Multimeter. If your thermostat has a Common wire, check the AC voltage between R and C. You should obtain 24VAC +/- 5VAC.   You do not have Multimeter? Touch and hold the R wire to the G wire. Does the blower fan come on? If the Blower fan comes on, You have a valid 24VAC power on the R wire.   

Report back here your findings and we can continue troubleshooting.

AC Cooling Wizard

[rrlafo]

thanks for the advice. We will check this tomorrow and report back.

[rrlafo]

Hi, we just tried your suggestion about holding the R wire to the G wire and the fan did not come  on. Do you have any other suggestions?

[rrlafo]

We were just able to get the thermostat to power up. Thanks for your help.

[CoolingWizard]

@rrlafo ,

This sounds like the when you removed the backplate, the R wire and the C wire touched each other and blew the fuse. You will need to go to the air handler. Find the panel that wires are inside of.  Look for the printed circuit board. There should be an ATC blade type fuse on the board.  

AC Cooling Wizard

[rrlafo]

Thanks for your help. We were able to get the Nest thermostat to work again.

[CoolingWizard]

@rrlafo ,

What did you discover was the source of the problem.  

AC Cooling Wizard

[rrlafo]

We don't know. After my husband took the thermostat off, reinstalled the wires, and put the cap back in, it started working again. He said he didn't do anything differently, so it is a mystery.