Installing a Google Nest Thermostat

We had an old thermostat (though not that old) that started misbehaving. It had Up and Down buttons that should have let you change the temperature setting, except that suddenly they stopped working. And when it is cold outside and you can’t raise the temperature inside, it does kind of suck. So it was clearly time for a change. I decided that for my purposes a Google Nest thermostat was the best option. There are two options here: a Learning thermostat that says it learns your patterns and automatically adjusts your settings as it learns them, and a simpler model that you control via your smartphone. Since the Learning thermostat costs twice as much, I decided to pass on it and go for the cheaper version. It does everything I want it to do. I can enter settings manually on my smartphone, which is fine, and also I can remotely control the temperature on my smartphone since it is connected to my home WiFi network. That is handy because I can change the temperature when we are traveling to save energy (no need to heat the house when no one is there) and then when the plane lands at the airport I can log in and set the temperature so it is comfortable when we get walk in the door. Very handy, that. If you want to know a little more about this thermostat, there is a Consumer Reports review you can read. You could order this from Google and have it shipped to you, but I found it at my local Lowe’s for the same price Google would charge, and got it immediately.

Next I checked out a video on how to do the install, and found this on YouTube. It really looked very easy to do. First, I went to the distribution panel and turned off the circuit breaker. As it happened, the furnace was running at that moment, so I immediately heard it turn off, which was a nice confirmation. Next, I removed the cover plate on the old thermostat. It was just a plastic plate that snapped on, and I got it off easily. The next step they recommend is to take a picture of the wires as they exist. That seems sensible, so I took the photo. it was bit dark in the hallway, so I used my flash for this photo. Then I opened up the box for the new Google Nest Thermostat, and found that unlike the video it did not come with a screwdriver and a cover plate for the wall, but that was not a biggie for me. I can fix the wall, and I have more screwdrivers than I really need, I suspect, including all on the mini-drivers for electronics.What was in box, importantly, was the labels to put on the wires. They should be color coded, but you really don’t want to somehow get your wires mixed up. Since this was a dark area, I pulled over a floor lamp to provide strong illumination. The wires in the old thermostat were connected to screw connections that were labelled, with labels like Y1, G, and so on. What you want to do is to disconnect one wire at a time, and put the appropriate label on it, so you can later connect it correctly to the new Google Nest Thermostat. The wires should be color-coded anyway, but you need to watch out for Y and Y2, or W and W2, and in my system the Y2 was blue, and the W2 was orange, so it is a good idea to label them, even if it is a finicky job.

With all of my wires labeled, it was time to remove the old unit. It was held in by two screws, one on each side, which in turn were held in the drywall by two wall anchors. I pulled the anchors and screws out and set them aside, and ended up using them later. With the screws removed, all I had to do was push the wires back through the hole in the middle of the unit, and now I had an ugly hole in my wall with wires coming out. I then got the Nest unit, and instead of screws on each side, it is held on by screws on top and bottom. The Nest unit comes with two long self-tapping screws, but I did not feel like that gave me a good solid connection to the drywall, so I used the screws and the wall anchors I set aside, and that worked much better. You put in the top screw first, then use the built-in level to level the unit, mark the bottom screw, and then attach it. The next step for me was the wires had all been attached to screw terminals in the old unit, so they had hooks formed on the end. Google Nest uses push-in connections, so I had to straighten out all of the ends. Pliers took care of that part.

Then to make the connections. On Google Nest there are push-in terminals on the left and the right, and they are labeled similarly to the wires. You hold down a tab on the back of each terminal, insert the appropriate wire, and release the tab to secure it. Pretty simple. But because they had had hooks, they had stripped more of the wire than was needed for my installation in the Nest, and leaving bare wire is not usually a good idea, so I cut off about half of the bare wire on each of them, using my needle-nose pliers with the built-in wire cutter. Then I needed to do a bit more research, since I still had wires left over. A little research online on places like Electronics Hub, plus a look at the Google documentation, led me to conclude that the added wires were for features I don’t have. The Black wire is a power wire, but the Nest doesn’t need that. The Orange wire, labeled W2 in my old system, is for a 2-stage heating system, and the Blue wire, labeled Y2 in my old system, is for a heat pump, which I also don’t have. So I put electrical tape around the ends of the wires for safety, and proceeded to put the display/cover of the Nest on. Then I took it off again after learning that I needed information from the back of it.

The installation at this point is done in the Google Home app on my phone, and in fact there are instructions for everything I already did that are on this phone app. I suppose I should have gone here sooner, but no harm. The one wrinkle I ran into is that it asked me which wires I had, and I answered for all of them, which lead Google to conclude that the Nest was not compatible with my system. But since I had already concluded that I didn’t need those wires, I just started over and this time told them I only had the four wires W, Y G, and R, and it was happy. Anyway, to get this going I had to read the QR code on the back of the display/cover, and once I had done that I could put it back. The Google Home app takes you through several steps, including, importantly, the WiFi network connection, which is the key to its usefulness. So I entered that information, then it downloaded updates from the Internet (because of course it did), and I was then ready to configure it. I set up daytime and nighttime temperatures, which for me means a bit higher during the day when I am working, and a little lower at night when I am sleeping. I then set the times, so it would start warming up a half-hour before my alarm goes off, and cools down a half-hour before bedtime. Of course, these can be changed at any time.

The final step is applying for my rebate. Our utility here, DTE, offers rebates for energy-saving appliances, and a smart thermostat qualifies for a $50 rebate. That makes it worth jumping through one or two hoops to get, so I filled out the paperwork. And now, as I write this, my home is nice and warm and my new thermostat seems to be doing a great job. The last step is to make it pretty. I found I could get the trim kit delivered overnight from Amazon, so we’ll see how that goes. I may need to remove and reinstall the thermostat, but that should be easy.

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