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Emerson

Sensi Smart Thermostat, 100 Years Of Expertise, Wi-Fi, Data Privacy, Programmable, Easy DIY Install, Works With Alexa, Energy Star Certified, Mobile App, ST55

    • Based on 20,809 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Dec 1 – Dec 3
Order within 12 hours and 42 minutes
Available payment plans shown during checkout

Style: DIY


Pattern Name: Thermostat


Features

  • PRIVACY PROTECTION*: Sensi wont sell your personal information to third parties
  • EASY DIY INSTALLATION: Use the built-in level and step-by-step app instructions for a quick installation. Works with HVAC equipment found in most homes. Common wire (c-wire) is not required in most applications
  • SAVE ABOUT 23% ON HVAC ENERGY*: The ENERGY STAR-certified Sensi smart thermostat can help you save energy with features like flexible scheduling, remote access, and usage reports
  • SMART MAINTENANCE: Sensi can help monitor the performance and efficiency of your HVAC system by delivering valuable usage reports, alerts about your equipment, and maintenance reminders like filter replacement
  • SIMPLE CONFIGURATION: Looks and feels like a thermostat. Has buttons and fits the same space as a traditional thermostat so you dont have to patch and paint your walls

Description

DIY your smart home with the Sensi smart thermostat. Compatible with most residential HVAC systems — no common wire (c-wire) required in most applications. You can trust Sensi as we do not sell your personal information to third parties. And Sensi comes with the dependable performance and reliability you can count on from our 100 years of HVAC experience. With our top-rated mobile app and easy installation process, customers of all comfort levels can make the switch to a Sensi smart thermostat. For more information on Compatibility, Energy Savings, and Privacy Protection, please refer to the “Product Documentation” section below.

Brand: Emerson


Model Name: Wi-Fi Thermostat for Smart Home, DIY Version


Product Dimensions: 1"D x 5.88"W x 3.75"H


Special Feature: Filter Indicator, Clock Display, Fan Control, Auto Changeover, Daylight Savings Time Ready


Brand: Emerson


Model Name: Wi-Fi Thermostat for Smart Home, DIY Version


Product Dimensions: 1"D x 5.88"W x 3.75"H


Special Feature: Filter Indicator, Clock Display, Fan Control, Auto Changeover, Daylight Savings Time Ready


Color: White


Specific Uses For Product: Boiler, Air Conditioner, Heat Pump, Furnace


Connectivity Technology: Wi-Fi


Included Components: Thermostat, free mobile app, 2 AA batteries, mounting hardware, wire stickers, installation guide, welcome guide with Sensi code, warranty booklet


Power Source: Corded Electric


Item Weight: 13.6 ounces


Voltage: 24 Volts (AC)


Material: Plastic


Shape: Rectangular


Display Type: LED


Screen Size: 5 Inches


Control Type: Button Control


Control Method: Voice


Connectivity Protocol: Wi-Fi


Mounting Type: Wall Mount


Style: DIY


Backlight: Yes


Number of Batteries: 1 AAA batteries required. (included)


UPC: 786710554827


Global Trade Identification Number: 27


Manufacturer: Emerson Climate Technologies


Department: Unisex-Adult


Country of Origin: Mexico


Item model number: ST55


Batteries: 1 AAA batteries required. (included)


Is Discontinued By Manufacturer: No


Assembly required: No


Number of pieces: 1


Warranty Description: 3 years.


Batteries required: Yes


Import: Made in the USA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Dec 1 – Dec 3

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Easy set up and works flawlessly!
Style: DIY Pattern Name: Thermostat
I was looking for a smart thermostat without breaking the bank and without the need for any fancy features like self learning based on your habits for example. Got a good deal on the Sensi and decided to try it out. I downloaded the app before purchasing and was able to check my existing wiring to see if the Sensi was compatible for my system. The app is simple and goes through the all the necessary steps for set up. You will need the C wire for this thermostat. Once I confirmed compatibility, and after delivery, following the instructions on the app took me through the process of removing the old thermostat and installing the Sensi. It was a very easy and logical process which even a novice at home improvement can follow. The only slight hitch in setting up the system was ensuring that the wire connection was secure - a couple of the wires came loose after I thought I had screwed them in. Really not a big deal but I gently tugged on the wires to ensure that they were not loose. The Sensi thermostat attaches to The wall by clipping into the wall plate that is provided. Luckily for me the old wall plate holes were in the right spot for the new Sensi wall plate. Before clipping the thermostat on ensure that the wires are flush with the wall as instructed by the app. Connecting to WiFi was fairly easy and it was done through the app on my iPhone. The thermostat is only compatible with 2G WiFi so you have to make sure your phone is connected to the 2G network while going through this part of the setup if you have a dual band router (you can switch your phone back to the 5G network after if you wish). WiFi connection was made quickly although the thermostat did take 30 or so seconds to be fully responsive to my phone after I thought the connection was completed (I initially thought I needed to go through a troubleshooting process but did not need to complete that process). Once fully connected you can easily adjust temperatures in the app, set up schedules and use a variety of options e.g. display humidity etc. There is also a geofencing option if you wish to use that. I set up my iPhone to be able to use Siri to adjust temperatures. You’ll need to set up your iPhone Home app for that. Once again the app runs you through all the steps to do that. I also set up my wife’s phone for her to have the feature that allows her to use Siri. Initial attempts to set her Home app to connect with the thermostat using Siri were unsuccessful until I realized that I could simply share my iPhone Home app settings with hers (just had to make sure to switch to the shared home app profile and not the original default one on her phone). If you do not wish to use Siri you can simply use the controls in the Sensi app and do not have to go though the Home app set up. I’ve had the thermostat for a week now and I love it. The thermostat is very responsive to changes made within the Sensi app or when using Siri (usually within 1-2 seconds). I also like that I can view ‘Usage’ within the app to see how long the furnace has been active. The app will also allow you to check to see if you are eligible for rebates based on energy savings programs for your area. Of course if you need to change app settings on the thermostat itself it is very easy to do so. There is a feature in the app that allows you to lock the wall display and only be able to change settings, temps etc through the app if you do not want people to change temps or settings through the wall display. Overall a great thermostat. Easy setup. Easy to use. Great features. Very responsive when using your phone. 5 stars plus!! ... show more
Reviewed in the United States on December 7, 2019 by Mel
    • Step by step app is AWESOME!!!!! Install app BEFORE removing old thermostat.
Style: DIY Pattern Name: Thermostat
We've had this thermostat a month and I really like it so far. It makes me think our old thermostat wasn't actually working for a long time before it started setting itself to 85°. Since it wasn't even programmable, I knew it had to go and if I was going to upgrade I may as well go with something just a bit more...modern than a set-temp-and-it-stays-unless-you-change-it thermostat. I'm going to do pros and cons below. I do want to say, I took my old thermostat off the wall first, wrote down all the wire colors and the letter each was connected to on a piece of paper. The app removes the need for pen and paper. I just used my pen and paper to place the flags mentioned below on the correct wires. Pros: 1. This thing is super easy to install. Open the box and there are instructions for you to download the Sensi app. Once the app is downloaded it has you choose which letter slots you have wires connected to (R, RH, C, E, OB, etc.). The app then tells you how to use the flags they provide to label the wires. For example I had a wire that went into a slot labeled "R", but Sensi only had "RH" and "RC" (I think it was RC), so the app told me which R my wire needed to go in. Not having any electrical wiring experience, the app was SUPER helpful. It even had you take a picture of your wiring to save to your phone, just in case. 2. The piece that attaches to the wall has a built in level. I am super annoyed when things aren't straight on walls, so this right here, was awesome. 3. The app is really easy to set up. I just have a daytime and nighttime cycle, but I could set up all kinds of things super easily. Vacation modes, turning the AC up when I leave the house... It was great. It even walked me through how to sync the app with my Google assistant and the Samsung Smart Things app, which I didn't end up continuing to use. (See cons #1) 4. The report that tells you how long your AC is running is really helpful as well, especially since we had issues last year with it not being able to keep up. We have better insulation and updated windows and it's nice to see they are working, even when it's 99° with a heat index at 112°. (See cons #2) 5. I like that you can do things like temp and humidity offsets, have the AC turn on to help maintain proper humidity levels (we live in Florida, so this is a big thing for me), change the cycle rate (ended up choosing this one over another brand because people had issues with not being able to adjust the cycle rate on that one), and easily turn heat boost on or off. (See cons #3) Cons: 1. It doesn't work with Bixby. This is something I don't really understand, but I'm guessing they assume if you're gonna use Bixby you use Smart Things? But I can just use Google for that instead. 2. The recent usage section only shows how long the AC ran that day, not which times it ran or how long at a time it ran. It would be nice to see how long the AC was running at a time, especially in the afternoon when it gets really hot. I have not yet gotten a monthly report since I got the thermostat mid-June and it's now mid-July. Interested to see what the monthly report looks like at the end of the month. 3. Sometimes I had to change settings a couple times before they "stuck". I found after changing a setting I needed to wait a few seconds before returning to the settings menu and that helped. 4. Shortly after I got the thermostat the AC drain line clogged. This resulted in my app/thermostat constantly saying cooling was on, but the AC wasn't running. My usage for that day was like 21hrs, but I know it wasn't actually on for the majority of that. Not really a huge issue, but you won't have an accurate reading for that day. Summary: Overall, this is a really amazing unit and I have been really glad to have it. It was seriously a breeze to instakl and set up and functions well. I do wish I could connect it to Bixby without using Smart Things and I do wish I had a more detailed daily usage report, but those are very small inconveniences. I normally keep our house at 78° during the day and 77° at night and sometimes that feels cold. I would often feel hot before and wondered if our AC was not working correctly, but it would seem it was actually the thermostat. Very happy with this purchase. ... show more
Reviewed in the United States on July 18, 2020 by Brandi

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