Sensi Lite Smart Thermostat, Programmable, WiFi, Easy DIY, Works With Alexa, ENERGY STAR Certified, ST25, Most Systems C-Wire Not Required, C-Wire needed with Heat/Cool Only & Heat Pump System – Black

I am impressed. First of all, watch the installation video in the item listing in Amazon. It is the first video for this Sensi Lite Smart Thermostat and it could not be anymore thorough than it is. If you want step by step it is that and logical. Then the app itself does the same thing, step by step as well. These folks actually cover all the bases. I know a lot about a lot of this but not AC and heating. It went off without a hitch, I have an old 4 wire system with no C wire and what is really cool is BEFORE YOU EVEN BUY you can d/l the app, go to the step as if you are installing a new one, go where you identify the wires on your old thermostat and it will tell you if it will work for you if you are not sure. I had this thing on, up, and connected to wifi and running in about 10-15 minutes, no issues. The only thing that concerned me was I was reading reviews before buying it and some people complained about it losing connectivity frequently. Only 3 minutes after installing that happened one time, and as I was reading the re-connect instructions it prompts you to, then it reconnected on its own before I could do it. For all I know that could have been my wifi burping, it does sometimes. >>IF<< I have that as a recurring issue I will be returning it because my router has plenty of reach and several devices further from it than this thermostat never lose connection. We shall see. I am just trying to give a full picture, I have no complaints but that was the primary reasonable one I saw in the negative reviews. So far I love the thing, the display is very cool, most of the time I will be bumping it manually walking by and that is a piece of cake. I have old eyes and appreciate the large numbers on the display too. I also like I can adjust it remotely from 4 states over as well. Honestly if you just want a remote app and basic functions with a schedule (I won't use) I don't know about all these others that cost way more why you would buy one of those. It is also nice looking. Oh yeah, it works on Alexa and other voice control things I also do not use. I think you get a lot of bang for the buck on this.

Works great on my old two wire (red and white) wire Pulse funace. Easy to install, connect to wifi, and I love being able to control the temp from my phone. My wife used to push our old thermostat slider up without being able to see what the temperature was actual set at, it had a couple second delay before it clicked so she would over shoot the temp and I would wake up sweating. With the Sensi Lite Smart Thermostat the room temperature displayed is easy to see and controlling temp from the app is super easy. I like how the display turns off while furnace is running but wish it had a dimmer feature for the display while showing room temperature as I worry it may eat through the two AAA batteries rather fast. Will have to see how long they last, but I am sure we will save a great deal on our energy bill with this amsome new thermostat.

Super easy to install and program. No more fights over the thermostat! Easy to set up temps and a time schedule to reduce use. The touch screen is the best! We use it on auto to keep the house a constant temperature. The setting are far more accurate than our previous thermostat. The build is sturdy as well as sleek. Looks good in the room

The Sensi Lite Smart Thermostat has a lot going for it, and in many ways it’s a good product, but the experience around power requirements, especially regarding C-wire usage, is misleading and needs to be addressed much more clearly. Because of that, this ends up being a four-star product instead of five. Starting with the positives, setup and general usability are strong points. The thermostat itself looks clean and simple, and the DIY installation process is mostly straightforward. The app is easy to navigate, Wi-Fi connectivity works well once established, and integration with Alexa is smooth. Programming schedules is intuitive, and once it’s online, remote control and monitoring work exactly as expected. From a smart-home and user-interface standpoint, Sensi did a nice job. Data privacy is another plus. It’s reassuring to know this thermostat isn’t built around aggressive data harvesting, which is something a lot of people are increasingly concerned about. Being Energy Star certified is also a solid benefit, especially for users trying to manage heating costs more efficiently. Where things start to fall apart is with the C-wire messaging. The product description strongly suggests that a C wire is not required for most systems, particularly heating-only systems. However, once you get into the actual installation process, the app and instructions indicate that a C wire is required. When reaching out to support, they confirmed the same thing. That contradiction is frustrating and misleading, especially for homeowners who specifically choose this model to avoid running new wiring. In real-world use, the power behavior reflects this issue. Even when using batteries and a C wire, the thermostat behaves inconsistently. When the heat kicks on, the display goes dark and the unit drops offline until the heat cycle ends. Once the system shuts off, the thermostat comes back on and reconnects. This makes it clear that power delivery without a proper, stable C-wire solution isn’t being handled as well as advertised. To be clear, the thermostat does partially function in these setups, but “partially” isn’t what most users expect from a smart thermostat. Losing connectivity and having the screen shut off during heating cycles defeats the purpose of having a smart, always-available device. Batteries alone don’t fully solve the issue, and the experience makes it obvious that the unit really wants a proper C wire, regardless of how it’s marketed. This doesn’t make the Sensi Lite a bad thermostat, but it does make it one that needs clearer expectations. If you already have a C wire and a compatible system, it can work well and provide a good smart thermostat experience. If you’re buying it specifically because you were told a C wire isn’t needed, you’re likely going to be disappointed or frustrated during installation. Overall, this is a good thermostat with a clean design, solid app, and useful smart features, but the power requirements need to be communicated more honestly and handled more robustly. If Sensi improves how the thermostat manages power without a C wire, or updates its messaging to better reflect reality, this could easily be a five-star product. As it stands, four stars feels fair.

I managed to get this working with my old brivis gas heating unit. This thermostat need C wire for gas heating. Old thermostat had only two wires. But the heater unit had C wire built-in which I rewired to connect to this thermostat to make it work. Setup is very straightforward. It's being one month since I installed and working perfectly. Happy with thr product so far. Note that this is a US product and it has US units and location/ weather information is only related to US or Canada. But I use Alexa and Google Home to align with my location in AU.

Great thermostat but make sure you have the right hook ups and wiring on your old furnace before removing your old thermostat or you will be in for a headache, basically do your research before tearing things apart and watch plenty of videos. Thermostat works great once it was hooked up and being able to control from your phone is a blessing.

Amazing product. I now can control temps from anywhere

This shouldn't be sold globally. You can't use it as a smart device outside Canada and the US.

I had tried 2 different units of the same model and they both exhibited the same issues. The problem was a loss of wi fi signal and the system was going into off mode. Tried calling the help desk but was but on hold hearing the same message for 20 minutes. There was no message stating that there was a back log of customers. Appearance and simplicity I give it 5 stars but automated functionality I have to fail it.