Sensi Smart Thermostat, Wi-Fi, DIY, Alexa, Energy Star Certified, ST55

This thermostat was incredibly easy to install and has already saved us a ton in just the first month or so. We purchased a new home in Minnesota but could not be there permanently for the first few months through March and April. In late March I installed this thermostat while at the house. The old dumb thermostat simply was running at a low temp while away which could have put the house at risk for cold weather. First off - Installation was simple. It took me about 10 minutes to install and it connected easily to our Wifi. I was able to set a couple different schedules and able to monitor them from our home in Colorado. I could see actual in home temps. See when the furnace was running and see outside temps forecast in the area. Upon return to our new home, I was able to use schedule which changed temps throughout the day based on our needs. I recommend this to our son and he installed one as well and loves it. A nice bonus was our local electrical company provide a nice rebate. I highly recommend.

The setup was very simple with the Sensi app making it easy to setup going through each step in a detailed manner. The thermostat was replacing an older Emerson so the compatibility was smooth and easy transition. The backing plate, which mounts on the wall, is nice in that it has a built-in level indicator. The kit includes screws and anchors along with wire labels. The Sensi app makes connecting to WIFI and programming the 7-day schedule extremely simple. The layout of the physical thermostat is very straight forward with nice big buttons for temperature setting to changing from heating to cooling. The Sensi app is very intuitive when setting temperature controls. Overall, a very nice and simple thermostat which is simple to install.

This is a must buy!! This was super easy to install!! Note: I think you are supposed to set up the app FIRST and THEN install the device!! But it worked just fine. I think it would have walked you thru the installation if we set up the app before installing the device. We removed the old thermostat’s cover plate then held up this thermostat w/o the cover plate. Then we took a quick pic of the old thermostat’s wiring with this thermostat’s inner panel. We removed the wiring in the order of this thermostat’s wiring diagram, too to bottom and removed the old plate. When we slipped this thermostat over the wires, they were all aligned an in order. Easy peasy to insert each one in order, top to bottom or bottom to top. Press down the wires, pop on the cover plate. Then we had to download the app, Sensi, and go thru the process to create a profile, select the wires inside our thermostat, and then zip thru the set up. So later, we were messing around with the app, setting up the schedules for when to cool/heat and at what temperatures to change and when. The app interface was SO VERY EASY!! It allows you to copy previous schedules or to create new based on existing schedules. It was really intuitive how to schedules and click thru everything. You can set schedules for when you only have heat on. And you can set schedules for when you only have the A/C on. AND you can set other schedules for when you have it on auto and it switches between heat and cool. Additionally, you can set any type of schedule combo for the week. So if you work from home, set a 7 day schedule. If you work M-F, set a 5 day schedule and weekend schedule. If you work 4-10s, easily set one schedule for your work week and a second for your 3-day weekend! Best yet! If you are a fireman or nurse and work a couple days on and a few days off , set up a schedule or two, call one long week and one short week or call it MTFSa/WThSu to show which days you are at work/home. I have never had one where I could schedule each day independently and was so easy to make multiple schedules. I can create one schedule for the days I work/am home, and then create a copy of that and just swap the days that I’m at work/home without having to schedule each and every day all over again. This is the easiest interface EVER!! ( I know my explanation doesn’t do it justice, but it is nice. I’m about to schedule another one for when I work nights. Then I just toggle between them at work if I find out I need to pull a double shift I hate new technology… but this was a dream… even for me!! Sensi, I tip my hat to thee for your user friendly product!! THANK YOU!!

I love it. It was easy to install (even with my odd, 1960's wiring), is simple to operate, and looks great in its niche area. I've tested its accuracy and, temperature-wise, it's always right on the mark. The best part about it is that it's connected to the internet and, if I'm in the family room on the opposite side of the house and feeling warm, I just grab my phone and make the adjustment. No more running from one end of the house to the other! Also, if my phone is within easy reach, I simply tell Alexa to set the thermostat to whatever temperature and I don't have to exhaust my fingers on the phone.

Pros compared to similar Honeywell smart thermostat (Wifi circuit died after power flickers): - Displays humidity value on unit and in app (nice addition). - Physical installation was very well guided through app. - Lower current price. Cons: - If you want to get alerts in case the temperature/humidity at a remote property encounter problems, this might not be a good solution. The default values are: temp hi/low = 99/45F, humidity=70%. Per website: "High and low temperatures, as well as humidity smart alerts, are not adjustable." The app does display current temp/humidity, but this isn't sufficient for remote properties. (Will probably get a stand-alone monitor that has alert settings that can be adjusted.) - Initial connection/registration failed, followed by thermostat panel being locked for a while (which I didn't enable). Later attempt ended up working (using same credentials/code), and the the unit and app then worked normally. I like the unit (it did cover the previous unit's footprint, btw), but am a little disappointed. Hoping Wifi connection is reliable.

"Out of all the thermostats I’ve used—including Amazon’s—this one easily takes the crown. Right out of the box, the quality is obvious: the body, display, and buttons are exceptionally well-coordinated to match most home decor. Beyond its sleek looks, installation is seamless and the functionality is incredibly flexible. Even though the companion app could use a slight UI refresh, its performance is rock-solid. The Alexa integration is a standout feature, giving me total control over timers and temperature settings even when I'm away at work. If you're looking to upgrade your home's thermostat, this is definitely the one to get."

After 3 hours trying to get the wifi to connect and subsequently waiting 40 minutes for support to answer the phone, the Agent sent this to try and rectify the issue: Thank you for contacting Sensi Technical Support. I apologize for this issue that you're having, but I can definitely assist you with a solution. It looks like your thermostat is having some trouble communicating through your router. Below are some router settings you can change to optimize connectivity. You may have to call your router's technical support service if you do not know how to make these changes. If your router is provided by your Internet Service Provider, contact them and they can remotely make these changes for you. • Update the firmware. Check to see if your router is running the latest firmware version available. o If you don’t see any firmware updates available on your router utility, make sure to check the manufacturer’s website for your specific model. They may have a firmware update available on their website. o If no updates have been available for the last couple of years, or if your hardware was manufactured prior to 2010, it may not comply with 802.11n standards. o If your hardware is provided by your Internet Service Provider, you may have to contact them to have your firmware updated. If no update is available from them, try resetting the router to factory defaults (see below).If that does not resolve the issue, ask to be provided with different hardware. • Reset your router to the factory default settings. It could be that some settings were corrupted over time because of electrical storms or power outages. Reference your router manufacturer’s instructions for assistance. *Please note, if you use a different SSID or passphrase after the factory reset, you will need to reconnect other devices to the network. • o Take note of your SSID (network name) and passphrase to reset after the factory default. o Set the security to WPA2 with AES encryption. o Set the 2.4GHz band to the 20MHz channel width. o Test to see if Sensi connects to your router. If it does, try adding back any custom settings to your router configuration. • Temporarily disable the 5 GHZ network, if you have a dual-band or mesh Wi-Fi network. This option typically can be found in the advanced settings of your router’s mobile app. Once Sensi is successfully registered and connected to Wi-Fi, you can re-enable the 5 GHz network. If you are still experiencing Wi-Fi issues, it may be necessary to separate your dual-band network. • Configure dual bands (2.4GHz and 5GHz) with different SSIDs/network names and passwords. This will allow you to connect the faster, higher data rate (streaming) devices on the 5GHz and keep the lower data rate devices (printers, thermostats, home automation, etc.) on the 2.4GHz. • Disable “MAC Address Filtering.” • Make sure your security is set to WPA2 with AES (CCMP) encryption. • Set the 2.4GHz band to the 20MHz channel width. • Consider using a Wi-Fi Analyzer app to see which channel (1, 6, or 11) has the least amount of traffic, and configure your router to a specific channel instead of "Auto." • Make sure the router is compatible with IEEE (Legacy) Power Save Polling. This is what the thermostat uses to stay connected to your network. • Sensi smart thermostat and Sensi Touch send TCP traffic on ports 80, 8091 and UDP traffic on port 8092. Sensi Touch 2 and Sensi Lite send TCP traffic on ports 8883 and 443. To receive over-the-air firmware updates, please make sure UDP traffic to port 8092 (34.233.82.197) and TCP traffic to port 80 (52.55.206.183) is open. For Sensi Touch 2, also make sure that TCP traffic to port 8883 (54.210.127.220) is open. This traffic needs to be able to navigate any network firewalls, proxies, or filter devices. This is insanity. All my other devices work fine off the gateway & router. The Agent gave up and told me to return the product - which will be done. How

I moved to the East coast last December. We have a six-zone boiler heating system with baseboard heaters throughout 4,200 sq. ft., on three floors (not bragging, just trying to give an idea of the size and complexity of the system). With six old-school manual thermostats spread throughout the house, it was nearly impossible to evenly regulate the heat during the cold winter, so some rooms were very cold and others too warm. I found myself constantly going up and down stairs to monitor temperatures and make sure I wasn't wasting heat or keeping areas too cold that would affect other zones. My boiler was installed in 2007, so it isn't very old and it's very efficient. However, it's a two-wire system with no C-wire, so the fact that 99.9% of "smart" thermostats on the market require a C-wire to operate was very frustrating. I stumbled across the Emerson ST55 and saw in the description that it could work either with or without a C-wire, so I called Emerson tech support to make sure before I plunked down hundreds of dollars on six thermostats that might not work. Tech support confirmed my fears that it would not work without a C-wire despite the Amazon description, so I kept hunting. Fortunately I found a YouTube review of the ST55 and the owner said he had been successfully using it with the same kind of two-wire system that I have for over two years. So I figured I'd buy one and see if it worked. Worst case, I'd send it back for a refund. The instructions inside the box clearly state that it will not work without a C-wire, but I ignored them and kept going. With only two wires it was a breeze to install. I put in the batteries, snapped it into the wall plate, downloaded the app, created an account and was ready for testing in about 15 minutes. I'm not sure if it's just my system or all boilers, but I didn't realize it doesn't turn on instantly when the thermostat temperature is raised above the existing temperature. So when I first tested it, I was bummed that it didn't work. But as I walked downstairs to the boiler, it was running! So I did some more testing, and found that there's about a 20-25 second delay between increasing the temp and the boiler kicking in. Granted it's only been a couple months since I got it, but I've played with it plenty and it's working great. Instead of a C-wire, the thermostat is powered by two AA batteries. The guy in the video said he's been using the same regular alkaline batteries for two years and they're still at 90% charge capacity, which is awesome. But I figure that even if I have to replace batteries every year, 12 AA batteries is a helluva lot cheaper than paying an electrician to rewire all six zones! On top of the six heat zones, I also have two central AC units. Thankfully those have C-wires, but I'm going to replace those thermostats with the Emerson ST55 also so that I'll have full control of all heating and cooling from one simple-to-use app. With any luck it'll go on sale on Prime Day so that I can save some money! :-) I can't speak to the Alexa integration as I don't use that functionality. But plenty of other reviewers have said it works fine. I appreciate Emerson's thoughtfulness in adding a built-in level to the back plate. I'm a stickler about things being mounted straight, so it was nice to not have to break out a level to make sure I didn't mount it crooked. As for aesthetics, the ST55 is nice. It's not too large to look obnoxious, but it has a good-sized display. And I'm not sure if it's just because I'm running it on battery, but the back light doesn't stay on constantly, so it doesn't light up a dark room at night (not too important in common areas, but important if you've got a thermostat in a bedroom). So, to make a long story short, don't believe Emerson. This thing really does work on a two-wire boiler heat system with no need for a C-wire!