A good deal
During the 2018 Black Friday season I found a great deal on the Nest Thermostat (3rd Generation) and decided to get that. I had heard great things about Nest from my friends and neighbors and this generation also supports remote sensors which is something I wanted to experiment with.
Step 1 – Checking all the prerequisites
I went through some YouTube videos for the installation steps and it looked pretty straightforward. Some of my neighbors who had done this install had warned me to make sure that the “C wire” for my furnace is actually connected. The common wire (C wire) is what supplies constant power to devices like Nest which need that to connect to wifi and also to power the screen. The nest article (https://nest.com/support/article/When-Nest-needs-a-common-C-wire) said that for my current configuration I do NOT need the C wire but given the experience my neighbor had, I decided to open up my furnace first to make sure I have this connected in case I needed it.
Opening up the furnace was not as easy but after a few tries I figured out how to get to the panel and was pleasantly surprised to find that the C wire was already connected. If you decide to check this as well, make sure that the power to the furnace is off from the main supply panel before you do this. Here is a picture showing the C wire (blue color) in my furnace.
Step 2 – Removing the current thermostat
Removing the current thermostat did not take much time but remember to take a picture of the wires which are connected so that in case you have to put the old one back, you know how it was connected. The Nest instructions were really good and labeling the wires also helped. Below is a picture of the wires that I labelled.
Step 3 – Installing the new Nest
The nest comes with a back plate which was a thoughtful thing for them to include as most of the old thermostats are rectangle and the Nest is round which leaves old paint or holes exposed in the wall. There are two big screws which hold the base plate of the nest and then the screen just snaps onto that. I decided to proactively connect the C wire as my neighbor who has a similar furnace needed to do that. This was a mistake which costed me 30 minutes of debugging later but again was a great learning experience to understand how the furnace really works. This is how things looked before I turned the furnace power back on.
Step 4 – Turning it on
When I turned everything on, the screen did not turn on! I searched online and some folks had suggested that you might need to charge the internal battery for some time before the screen can power on. So I connected the Nest to a micro USB connector and charged it for 20 minutes. When I put it back on, the screen turned on but then it was showing an error that the Rh terminal did not have power
Some more searches online resulted in me landing on the Nest website which had a troubleshooter. Usually those things are really silly and rarely help but since I did not have any other ideas on what is causing that, I decided to give that a try. It kept recommending different wire configurations to try and on the 4th attempt I was really surprised with what they told me. The troubleshooter clearly said that I do NOT need the C wire and asked me to remove that completely. Once I did that, everything worked like a charm and basically all the problems I had were self inflicted :). I installed their app on my phone and began playing around with it.
Nest recommends that you keep adjusting the temperature to your liking for the first few days and then it “learns” what to do. This seems to be some kind of marketing gimmick to me as all it is doing is setting a schedule behind the scene. The app had some cool features of showing the usage of the furnace and the concept of safety temperatures where the furnace automatically comes on if the temperature drops below a certain point (great when you are away for an extended time). However I was really impressed with how Nest had made a great user experience for a seemingly boring product like a thermostat. The dial to change the temperature is their signature hardware design and it works beautifully.
The thing I miss the most and honestly seems like a basic feature is the ability to temporarily hold the temperature and snooze the schedule. Other than that, I have had no issues with it so far after using it for a couple of months. The first world convenience of changing the temperature from your phone is definitely a plus. I am planning to add a sensor on our bedroom to control the temperature better in our two level home. Overall I would definitely recommend Nest thermostat to anyone who is looking for better control over their thermostat.