Nest thermostat troubleshooting and why I ditched the Nest

nest thermostat troubleshooting

This post will help you troubleshoot your Nest thermostat issues. After 2 years of using the Nest I went back to the Honeywell thermostat. Before I get into that, let’s troubleshoot your Nest thermostat.

These Nest troubleshooting issues are the most common technical issues and the ways to fix the problems with your Nest thermostat.

The instructions were provided by the manufacturer and are quite easy to follow. You shouldn’t face any challenges during the troubleshooting process – guidelines are quite simple. However, if you cannot perform the task on your own, don’t hesitate to contact the repair service provider.

Nest thermostat Troubleshooting

If the Nest thermostat isn’t getting enough power from W or Y and there is no Common wire. This is a BIG ONE! Most thermostats require a battery, usually AA, to be changed out about once a year. The Nest thermostat doesn’t take batteries. It’s internal battery is charged via your AC, like an alternator charges your car battery.

Nest thermostat has power issues

If your Nest thermostat isn’t getting enough charge for whatever reason, it will not work properly or cause your AC to power on and off.

One way you can resolve this is by connecting your Nest to a constant power wire from the furnace. I’m no electrician or furnace expert but I was able to handle this.

While we find that in the vast majority of homes the Nest Thermostat can charge its built in battery by power sharing from the regular heating and cooling wires. But in some rare cases a common wire is needed to deliver consistent power to the Nest Thermostat while allowing normal operation of the heating and cooling system. If there is a common wire installed the Nest Thermostat will not power share.

Power sharing, I have found, to be a pain in the rear. It causes issues with the Nest thermostat’s operation.

If the Nest doesn’t turn on after installation and the Red LED is blinking on front, the Nest thermostat battery is low and needs to be charged. If you leave it where it is, the Nest will slowly charge and eventually turn on. This can take an hour or two.

The Nest thermostat will not turn on until it senses both the wires are hooked up and power is coming to those wires. Check your wire connections. Here’s a photo of what my Nest wires look like.

nest thermostat troubleshooting

If your Google Nest thermostat won’t turn on and you see a blinking red or green light, or no light at all, there could be a power issue or your thermostat may have frozen during a software update. Here’s how to troubleshoot.

If there’s a power issue, your thermostat’s battery will drain and it will turn off Wi-Fi, the display and other features to preserve battery life.

Before you start troubleshooting your Nest thermostat

  • Your Nest thermostat should automatically turn on once it’s connected to your system and your system is powered up.
  • If you see a blinking red light at the top of your Nest thermostat’s display, you’ll need to wait until the battery is charged before you can use it.
  • During regular use your thermostat’s screen may automatically turn off after a period of inactivity, but it should also automatically turn back on when it senses someone is nearby or when someone uses the app to control it. I have found this to be a problem, as the battery in the Nest thermostat will not charge properly if the AC has been off for awhile. The Nest relies on the AC running to charge.
  • Your Nest thermostat uses the voltage from your system’s wires to keep its internal battery charged. If the power to your system is switched off or there’s a blackout, the battery has enough capacity to keep working for a while. Your thermostat will also turn off features like Wi-Fi to preserve battery life before it must turn off completely.
  • Make sure your Nest thermostat is connected to your wifi.
  • To force the AC to kick on, either on the NEST app or the NEST thermostat itself, turn the AC down to kick on at least 10 degrees cooler than what you want it set at. This will for the AC to kick on. Let it run at this setting for awhile, maybe an hour, to get the Nest battery charged up.

I have run into all these issues with the NEST thermostat, and while I thought the Nest thermostat was really a cool device, I NO LONGER USE IT!


Why I no longer use the Nest and never will

It was a really hot day in July and the AC wasn’t staying on for more than 5 minutes! I did all the typical troubleshooting including what I wrote about in this post.

Other troubleshooting methods I tried, which worked for about a couple hours, included powering everything down! I turned off the furnace, all power to furnace and AC and even pulled the breaker plug to the AC unit outside of the house.

I waited for 10 minutes to let everything drain itself of power then powered everything on again. I turned the Nest thermostat 10 degrees lower and it worked! Only for 20 minutes.

In frustration and desperation, as a test, I removed the Nest from the wall and replaced it with the programmable Honeywell thermostat I bought just 2 years before.

The honeywell takes a double AA battery so I replaced that with a fresh one and connected everything up.

GUESS WHAT? I have AC and it’s been a month now! No issues!

You know what else I noticed? For some reason the Nest thermostat was always 2 or 3 degrees behind what the house temp was. The Nest thermostat could never catch up and the AC was always running!

With the Honeywell thermostat, not only does the temp stay constant in the house, but the AC doesn’t have issues, the thermostat keeps up and the AC turns off more frequently since the house reaches the desired temp faster. The Honeywell thermostat keeps up and does a better job!

Sure, it was cool to have the Nest thermostat app on my phone where i could play with settings and such, but as a general rule, you should set the desired temp and forget it. This is the best way to achieve the best cooling in your home and save money.

With the Nest thinking on its own about when to turn on or off, by sensing movement, it’s always going to try and keep up. Think about it. IF you set it to be off for 8 hours in your home while you’re at work or out, it will kick on when you get home. The Nest thermostat will be struggling to keep up for all those hours it was off. This wasted electricity.

Another reason I ditched the Nest thermostat is because I don’t want google in my home. All google products report back to the mothership. It knows when you’re home via sensing your movements and learns your lifestyle.

It’s bad enough we each keep a GPS tracker on us at all times (your phone) and now google is monitoring when you’re home to talk to your AC. As a side note, I no longer use google as a browser, I use duck duck go. Google is a mass money making machine and they do so by collecting all the data they can on you.

If you love your Nest, that’s great. You have to go with what you’re comfortable with and what you enjoy. These were just my reasons for getting rid of it.

I hope this Nest thermostat troubleshooting guide has helped you.

You can purchase Nest thermostats HERE on Amazon and check out the line of HONEYWELL thermostats HERE. Honeywell thermostats, as you know, are very popular, made very well, and have been around for a very long time.

Steve