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Sensi Wi-Fi Smart Thermostat for Smart Home

  • Reduce energy costs with remote access, scheduling and geofencing
  • Install in 30 minutes or less - C wire not required in most cases
  • Works with Amazon Alexa, Google Assistant and Apple HomeKit
  • See More Details

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Product Overview

From across the room or across the country, your Sensi Wi-Fi thermostat makes it easy to remotely control and schedule your home comfort - Anytime. Anywhere. Sensi thermostat does not require a common wire (c-wire) for most installations, so it is compatible with the HVAC equipment in many homes in U.S. & Canada. A c-wire is required for heat-only, cool-only and heat pump (without aux) systems, and for use with Apple HomeKit. Check to make sure it will work for you at sensi.emerson.com/compatibility. Put your comfort on your terms with geofencing or 7-day scheduling option with the ENERGY STAR certified Sensi thermostat. Both energy saving features you save about 23% on your HVAC energy usage, so you can save money without compromising your comfort. Energy savings calculated by comparing operation time for a nationwide sample of Sensi users with temperature adjustments averaging 4°F vs. users with no adjustments. Savings vary based on equipment type/condition, insulation, climate & temperature adjustment size/frequency. Based on survey results of 2120 respondents that purchased and installed a Sensi thermostat in 2018, approximately 70% reported installing in 30 minutes or less. Adding a common wire may impact installation time. Does not work with electric baseboard heat and some other systems. System requirements for mobile app: iOS - 10.0 or above Android - 4.2 or above (5.0 or greater to use the Geofencing feature).
  • Reader's Choice BEST SMART THERMOSTAT by PCMag and Editor's Choice BEST VALUE SMART THERMOSTAT by USA Today's Reviewed
  • Save about 23% on HVAC energy: the ENERGY STAR certified Sensi thermostat helps you save on your HVAC energy costs, with features like geofencing, 7-day flexible scheduling, remote access and in-app system usage
  • Most install in 30 minutes or less: use the built-in level and step-by-step app instructions for a quick installation, skip any extra work painting or patching the wall thanks to the standard thermostat size
  • Extensive compatibility: works with the HVAC equipment found in most homes - a c-wire is required for heat-only, cool-only and heat pump systems, check system and router compatibility at sensi.emerson.com/compatibility
  • Smart home compatible: works with Amazon Alexa, Google Assistant, Apple HomeKit (c-wire required), and Samsung SmartThings smart home platforms
  • Sensi multiple thermostat manager: control, batch and group unlimited number of thermostats from a single dashboard for just $10 per thermostat per year
  • Usage reports: monitor current day and historical heating, cooling and fan runtimes right in the app
  • Get rebates: find utility rebates in your area through the rebate finder at sensi.emerson.com/rebates
  • Control from anywhere: remotely control your home comfort from your smartphone or tablet using the Sensi mobile app for Android and iOS devices
  • Smart alerts: Sensi features smart alerts to help detect extreme temperature and humidity levels in your home
  • How to install and replace your thermostat

  • Click here for more information on Electronic Recycling Programs
  • California residents

Info & Guides

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NameSensi Wi-Fi Smart Thermostat for Smart HomeSensi Touch Wi-Fi Smart Thermostat with Touchscreen Color Display, C-Wire RequiredNest Learning Thermostat - Smart Wi-Fi Thermostat - Stainless SteelNest Learning Thermostat - Smart Wi-Fi Thermostat - Mirror Black
FeaturesAuto Changeover,Backlit Display,Battery Back-Up,Built-in Wi-Fi,Daylight Savings Time Ready,Outdoor Temperature Display,Vacation ModeAuto Changeover,Backlit Display,Built-in Wi-Fi,Daylight Savings Time Ready,Touch Screen,Vacation ModeDaylight Savings Time Ready,Vacation ModeRemovable Interface
Thermostat CompatibilityUniversalUniversalUniversalUniversal
Wire ConfigurationC-WireC-WireC-WireC-Wire
Control TypePhone ControlledPhone Controlled,TouchscreenDial,Manual,Phone ControlledDial,Manual,Phone Controlled
Heating & Cooling System Type2 Stage2 Stage2 Stage2 Stage
Power OptionsBattery,C-wire,HardwiredC-wireBattery,C-wire,HardwiredPlug-in
Thermostat ShapeRectangularRectangularRoundRound
Voltage TypeLow VoltageLow VoltageLine VoltageLine Voltage
IncludedBatteries,Display Base,Mounting Hardware,No Additional Items IncludedDisplay Base,Mounting Hardware,No Additional Items IncludedMounting Hardware,Trim PlateMounting Hardware,Trim Plate
View ProductView ProductView ProductView Product



Display height (in.)
Display width (in.)
Product Depth (in.)
.938 in
Product Height (in.)
3.75 in


Battery Power Type
Battery Size
Color Family
Control Type
Phone Controlled
Auto Changeover,Backlit Display,Battery Back-Up,Built-in Wi-Fi,Daylight Savings Time Ready,Outdoor Temperature Display,Vacation Mode
Heating & Cooling System Type
2 Stage
Hub Required
No hub connection available
Batteries,Display Base,Mounting Hardware,No Additional Items Included
Pack Size
Periods per Programmable Day
Power Options
Power Options
Remote Access
Remote Access
Requires Hub?
No Hub Required
Smart Home
Smart Home Enabled
Smart Home Protocol
Smart Technology
Intuitive Scheduling,Smart Home Hub Compatible,Smart Phone/Android App Compatible
Thermostat Compatibility
Thermostat Product Type
Thermostat Shape
Thermostat Type
Heating and Cooling
Voice Control Hub Required
No Hub Required for Voice Control
Voltage (v)
Voltage (volts)
Voltage Type
Low Voltage
Wire Configuration
Works With
Alexa, Apple HomeKit, Siri

Warranty / Certifications

Certifications and Listings
Energy Star
Manufacturer Warranty
3 Years

Questions & Answers


Is there a program to allow the fan to ciculate even when the ac unit is off?

Asked by Srqntv June 15, 2021

I don't think so. The fan can be turned on manually with out heat or cooling on, but I don't see a way of programming it to come on or off on a schedule. In manual mode it would be on all of the time.

can fan be set to circulate air only

Asked by Daves May 23, 2021

Yes, one touch of the fan button and you are on circulation. Touch again and the fan is controlled by your heat/air settings.

Will the thermostat work with ADT control panels

Asked by Ajjromer May 22, 2021

No, totally different system.

Under what conditions does the second beat stage turn on?

Asked by Dizzer February 6, 2021

It should react to the temperature and turn on if the temp drops (or rises if you have AC).

If the inside temperature in my summer place falls below the low setpoint of 45 degrees in the wi...

Asked by GT February 5, 2021

I had a heating problem also at the cabin but the Sensi showed there was a problem. I went down and found out we had a power outage that tripped the breaker, got it back on line and the internal temperature was on the screen, 42 and the setting was at 55.

Is this compatible with xfinity home

Asked by Bigdawg41 February 5, 2021

yes, it is

I have one of these thermostats in my home in Michigan and it shows the humidity. The description...

Asked by Dee January 31, 2021

Yes but I don’t know if it is right

Does this work to replace a thermostat with an emergency heat option?

Asked by Sarah January 18, 2021

Mine has an AUX heat function on the display.. I presume that is the same. If so, then I'll say yes it does. Here in the desert southwest, we have little need for AUX/Emergency heating (rarely cold enough).

Can I operate from from another state?

Asked by Trucker1 January 17, 2021

If you have a wifi access or data plan with your smart phone, you can access the thermostat from the other side of the globe. At the present time (I haven't checked), there's no app that allows access from a laptop/desktop computer. Smart phone only. Works with Alexa voice commands, too.

The installation video says to turn off the heating & cooling equipment. An older model I had sai...

Asked by BML January 15, 2021

I would turn off all power to the system until you install the thermostat - for safety reasons. Not a big issue.

Sensi Wi-Fi Smart Thermostat for Smart Home - page 2

Customer Reviews

  • 4.5
    out of 1,583 reviews
  • 88% recommend this product
Filter by:
Showing 1-10 of 1,583 reviews
It totally suits my needs. The video step-by-step instructions made it easy to install. And havin...
It totally suits my needs. The video step-by-step instructions made it easy to install. And having the convenience to control the temp via my smart devices is fantastic. All in all, I would highly recommend the Sensi thermostat to any and everyone.
by LadyDIY
Good wifi thermostat for the money
Very happy with my purchase. Good value. Installation was a snap with the app. There is even a bubble level mounted inside the mounting plate. The app guides you every step of the way. All settings and schedules are done through the app. Also displays humidity on the screen. Connected easily to my wireless network. Now I can check and adjust my thermostat from anywhere in the world!
by Randy
No 'C' Wire, Still Works
I first tried to install the Holiday Special Honeywell Smart Color thermostat. No luck as my spare wire did not pass as the required C wire. This Emerson Sensi model however seems to work! Because of the lack of a C wire, some features are not available such as the ever on back light. Regardless, with batteries and three basic wires from my 1990's heating system, I now have a modern, WiFi enabled, functional thermostat. Only time will tell if it really helps save on heating costs, but I have high hopes. Easy to install, easy to use without a dedicated C wire. I would recommend this product if you have an older furnace and want to upgrade your thermostat to a 'smart' one.
by Meaghan
8 people found this helpful
Awesome Wi-Fi Thermostat!!
So easy to install and pair with your Wi-Fi. Love it...like the AC protection and circulation Fan Only setting options. Highly recommend it. Like the Sensi app to control at my finger tips via my phone! Highly Recommend!
by PapaT
2 people found this helpful
Perfect for me
I love it! The price was right, it was easy to install, and it works just the way it's supposed to. What more is there that can be said? GOOD JOB!
by blackboxtoo
3 people found this helpful
Works great
Love this unit it works great and I can control it from my phone
by Ah
2 people found this helpful
Just works
This thermostat just works, it was very easy to install, love their app. No issues whatsoever
by Vlad
1 person found this helpful
Amazing product for an amazing price
Worth every penny, this wifi thermostat is very easy to install. The mobile app is very user friendly so much so that even my wife likes to use it and she is very technologically illiterate. So it is a major win for our household, and it has even improved my A/C's performance. My electric bill is looking real good.
by zzhuffxx
1 person found this helpful
Very easy to install and use
Best thermostat that could be built for me. I like smart equipment and simplicity combined. Screwed right in place of my old Honeywell thermostats. Same screw hole configuration. I installed two, up stairs and down stairs. They connected to my WiFi instantly. The app is very easy to use. I like the usage report in the app. And the fan circulation percentage settings very useful. I like the three buttons on the unit for old school control habits. I love its app weekly programming ease of use. I could not be happier. I probably just jinxed my thermostats.
by Hammy
4 people found this helpful
Just works
I really love our Sensei WiFi Thermostat. This coupled with the Energy Star rebate and we got this for $25. It works well, responsive to changes on the app, gives great stats on usage, and lets me control from anywhere. No nagging emails with the account either. Best purchase in a while.
by Highfall
5 people found this helpful
Showing 1-10 of 1,583 reviews