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Review: Emerson Sensi Wi-Fi Thermostat (1F86U-42WF) – Smart Thermostat Guide

Review: Emerson Sensi Wi-Fi Thermostat (1F86U-42WF)

Review: Emerson Sensi Wi-Fi Thermostat (1F86U-42WF)

Our Emerson Sensi WiFi thermostat rating:

Sensi at a Glance

Emerson Sensi WiFi Thermostat and companion app on an iPhone

Say hello to Emerson Sensi, a WiFi thermostat with all the features you want and a price point that will leave enough cash left over for dinner at the fanciest place in town.

What if I told you that you could get all the power of a WiFi enabled thermostat (remote control, ease of scheduling) at half the price of the flashier thermostats?

Meet the Sensi.

Technically, its full name is the White-Rodgers Emerson Sensi Wi-Fi Thermostat, but we’re gonna just go with Sensi for short. And it is a great thermostat, especially if all you care about is accessing your thermostat remotely and setting schedules with ease.

March 2016 update: Amazon Echo now supports Sensi! Give a command in the form of, “Alexa, set my bedroom temperature to 64” or “Alexa, increase the temperature in my home” to try it out.

[ Shop for Amazon Echo | Amazon Echo review ]

Emerson Sensi smart thermostat mounted on a wall

Note: Our installation site did not allow for hiding the wires in the wall, but most homes allow for hiding wires in the wall behind the unit.


  • Costs $100+ less than Nest and ecobee3 with few (if any) real sacrifices
  • No C-wire required for most systems – the only exceptions are heat pump systems, 2-wire heat-only systems and AC-only systems
  • Looks like a traditional thermostat, which might suit your home better than some of the more futuristic-looking thermostats
  • Amazon Echo integration and Wink Home Hub integration for centralized control of your home’s smart things
  • +/-1 degree swing range
  • On-screen weather conditions
  • Humidity sensor
  • PIN lockout – a recent update lets you prevent kids, employees, visitors, etc from adjusting the thermostat in your absence
  • Check humidity, temperature, fan settings, auto/off toggle from app
  • Backlight button on top of unit illuminates the screen on demand
  • Simple, straightforward – no need to mess with any learning algorithms or geofencing
  • Great app and web portal – everything you need is in the app, no need to get off the sofa 🙂
  • Manage multiple Sensi thermostats from one app
  • Remembers programs through power loss
  • 3 year warranty
  • Overall simplicity and ease of use


  • No usage reports
  • Not a humidistat replacement – you have been warned

Our Rating

We think the Emerson Sensi is fantastic and award it 4.5 stars out of 5.

If you’re on a budget (or just don’t want to pay $250 for a thermostat), look no further than the Sensi.

Yes, it’s not as full-featured as many smart thermostats (you won’t get fancy-pants stuff like motion sensors or geofencing), but to many homeowners that’s just fluff anyway. With an average rating of 4.5 out of 5 stars on Amazon.com, the Sensi is a well-liked alternative to flashier smart thermostats. It’s like a programmable thermostat that you can schedule yourself and control through your phone. To get a full 5 stars all we would want are some usage reports, but that’s being super picky, especially at this price point.

The Ecobee Smart Si (our review) is similarly featured and priced, but we like the look of the Sensi more and we appreciate that it works in more HVAC systems without having to also set up a power extender kit (which isn’t even included with the Smart Si).

See the Emerson Sensi on Amazon.com

No-nonsense thermostat with modern sensibilities

The Emerson Sensi thermostat lets you control your thermostat from your phone without any additional complexity. Emerson is an old name in thermostats (some 75+ years) and has decades of experience working with a huge variety of HVAC systems. Many reviewers who had problems installing or maintaining a stable connection with Nest found the Sensi to be much more reliable.

No C-Wire required! (For heating & cooling systems)

Why run wires if you don’t have to? Sensi is designed with low power consumption in mind, and works in a majority of combined heating and cooling system homes without a c-wire. The two AA batteries provide backup power and are expected to last months before needing replacement.

The exceptions, of course, are heat-only and cooling-only systems. It is not possible to run the WiFi features of the thermostat on AA batteries alone (unless you like changing batteries every couple hours). If this describes your home’s HVAC setup, you will actually need to run a c-wire or consider a solution like Venstar Add-a-Wire.

See also: Sensi’s C-Wire compatibility guide

Features include:

  • Program each day individually or in groups
  • Precision temperature control (+/- 1 degree)
  • LCD display with clock, inside temp, outside temp, system status
  • Select F or C
  • Access schedules, settings, current mode of operation via app over WiFi
  • Permanent on-unit memory

Easy, flexible Scheduling

If you have a predictable schedule, it’s easy to program it in.

If your schedule varies wildly by day, it’s easy to override the programming.

The Sensi lets you…

  • Change temp 10x a day if you want
  • Set a different schedule for every day of the week
  • Set different schedules for weekday/weekend
  • Set up custom schedules (ie: a “work from home” schedule)

With the Sensi, you put your schedule in yourself. The Sensi doesn’t attempt to “learn” anything on its own.

Great app, easy to use

Scheduling, overrides, and settings are right there on the smartphone app, which is nice looking and easy to figure out. The app is available for iOS (reviews and screenshots) and Android (reviews and screenshots). The worst complaint about the app seems to be the occasional inability to connect.

Emerson Sensi app screenshots

Set and edit schedules from your smartphone or tablet.

Amazon Echo integration

In March 2016, Emerson and Amazon announced Amazon Echo integration for the Sensi! The smart thermostat can now be controlled by Amazon Echo and Alexa, Amazon’s cloud-based voice-controlled service.

There are no additional fees or apps to use, just let Echo discover the Sensi and start issuing commands.  For example, you can say, “Alexa, set the upstairs temperature to 72 degrees”.

See current stock and prices for Amazon Echo on Amazon.com

Wink hub integration

In July 2015, Sensi added integration with the Wink Home Hub, a centralized home automation system that lets you control all of your connected devices from one app. You can use the free Wink app instead of Sensi app, if you prefer (iOS | Android).

Wink Hub 2

Humble, inobtrustive design

It just looks normal, and for a lot of people that’s a good thing. It’s very slim against the wall (just a bit more than an inch thick) and the white plastic body won’t attract finger smudges.

Below is a manufacturer photo labeling the Sensi’s on-unit buttons and screen elements.

Emerson Sensi button guide

Installation and setup

You’ll need to make an account with Sensi (through the app) when you set up your new Sensi thermostat and register your device. Be sure to write down the access code found on the back of your Sensi before you mount it to the wall, because you’ll need it during setup (if you forget, though, no big deal – it’s also included on a sheet of paper in the box).

On my first setup attempt I accidentally neglected to finish registering the Sensi thermostat – and that prevented it from fully integrating itself with my app. So that’s my one bit of advice for setup: be sure to complete the registration step, or else you’ll be wondering why your thermostat doesn’t show in the app.

Once you’ve got the setup complete, your Sensi app will change to reflect the current mode and temperature. (Yes, it was cold when I set this one up!)

The upper right corner of the app’s default screen shows today’s high and low temperature, as well as current temperature and location.

(I’ve edited the name and location out of these screenshots because this is one of my own, not manufacturer’s screenshots.) 

From here, you can set up schedules and adjust the current target temperature via the “hotdog” (or “hamburger”) menu in the upper left corner. A tray pops out to show schedule options, settings, account info, access to help, and more.

Everything in the app is straightforward and easy to figure out. There aren’t a lot of options, just a weekly schedule (you can build a fairly sophisticated schedule to accommodate shift work or children’s schedules) and some settings.

Sensi Tech Specs

Model Number

  • 1F86U


  • Main unit: 5.875″ wide x 3.75″ tall x 1.125″ thick

Wireless (Wi-Fi)

  • 802.11n
  • SSL/TLS-enabled remote control

Nearly all modern wireless routers meet these standards.

In the box

  • Sensi Wi-Fi thermostat
  • Thermostat base
  • Quick start guide
  • Mounting screws
  • Wire labels
  • Security code card for hooking up with the web portal and app
  • 2 AA batteries

Sensi System Compatibility

From the manufacturer:

  • Gas, oil, radiant heat, geothermal
  • Up to 4 stages of heat and 2 stages of cooling
  • Conventional systems (2-wire heat only and 2-wire cool only systems require a C-wire)
  • Heat pumps
  • Dual fuel heat pump system – automatic balance point control with no additional sensors required

Incompatible systems include line voltage and proprietary systems, gravity furnaces, in-floor, or millivolt wall systems. However, some systems can be made compatible by adding a 24 volt transformer. For assistance, Emerson recommends contacting Sensi Support.

More Sensi Info & Reviews

The Sensi is a smart choice if you want the convenience of a WiFi enabled thermostat from a renowned company and won’t miss features like geofencing or usage reports.

Note that Amazon features two versions of this thermostat, the “DIY-Install” version and the “Pro-Install” version. They are the exact same thermostat, but the “Pro-Install” version comes with a longer warranty and costs less. Win win!

Check current Emerson Sensi (pro install) stock and prices on Amazon.com

Note to readers: Some links on SmartThermostatGuide.com are affiliate links. Read our full disclosure policy here.

Emerson Sensi WiFi Thermostat


Ease of use


Power options




Integration with home automation systems



  • Easy to use app
  • Tight control over daily schedule
  • Straightforward, simple design
  • Access from anywhere via app
  • Budget-friendly price


  • Requires a c-wire in heat only / cool only systems
  • No usage data
Review Date
Reviewed Item
Emerson Sensi WiFi Thermostat
Author Rating


27 Responses

  1. Cyril says:

    I believe the Pro version is cheaper because you have to have it installed by a HVAC certified company in order to benefit from the 5 years warranty. The DIY version has the consumer grade regular 3 years. You can still buy the Pro version but if you need to use the warranty within the 5 years, you will have to call a company to have it switched and honor the warranty which can cost you more at the end.

  2. HR isn’t but handed by way of, and so they say that it’s
    not within the API, so it seems like it will not be in different third occasion apps
    but both.

  3. Ken says:

    I intend to purchase the Emerson Sensi to help manage peak demand using a veryspecific schedule and like that there are up to 10 daily schedules so I can coordinate it with a second AC unit thermostat. Can it be scheduled to set a temp at any time (not just 15 minute intervals) meaning… at 3:40pm and set to 72 and then at 4:25 set to 80? Thank you.

    • Ryan says:

      Ease of use


      Power options




      Integration with home automation systems


      I just installed mine and no you cannot set it to specific times, only 15 min increments.

  4. david kirk says:

    looking to use this for my heat pump / forced air propane dual fuel system.

  5. Mike says:

    It was upgraded automatically and now has a lock feature (kids, businesses).
    Also, I think it always worked with Wink home automation or it too was added.

  6. […] a budget-friendly smart thermostat (and not a home automation hub to go with it), check out the Sensi […]

  7. Nick Amundson says:

    Great product. I’ve had mine for almost a year. There is one huge missing feature, however, and it’s not usage reports. Many users that I know (I’ve had 4 friends install one) have complained about the inability to set their own custom swing. If the swing is 1 degree and the set temp is 70, the system will heat at 69 and turn off at 71. If the swing is 2 degrees and the set temp is 70, the system will heat at 68 and turn off at 72. This feature would allow more user control for better comfort and would also prevent short cycling, which can quickly damage equipment. Please give us this important feature! Thanks Team Sensi!

    • sdagdgsa says:

      i believe you can essentially change the differentials by the “cycle setting” in the app. slow = longer cycles = longer “swing”.. —-> fast (the opposite)

  8. Paul Olinski says:

    I live in rural Wisconsin and don’t have cell coverage yet. I can set up the units at our vacation home on someone else’s smartphone not my clamshell burner, or a laptop. After that I can access the app with any browser based device and erase the app on the borrowed smartphone. Seems like a small improvement that would be easy to implement would be browser based setup.

    We have two new furnaces with two central a/cs that two thermostats should manage well remotely. Can’t wait for them to arrive.

  9. […] If you don’t have a smart thermostat already and you’ve always had your heart set on a Nest, this is the best Nest yet – go for it. It’s definitely not worth switching over from our top pick, the Ecobee 3, and if all you really want is a WiFi thermostat (and don’t mind plopping down less than half as much cash), check out the Emerson Sensi. […]

  10. Jay says:

    Ease of use


    Power options




    Integration with home automation systems


    A quick note – this unit supports only US and Canadian time zones. I’ve got mine installed on the east coast of Australia, and it’s a bit painful using Hawaiian time (20 hours behind) to schedule! Emerson support have committed to consider other time zones, but I’m not holding my breath.

    Also, the Honeywell units permit 0.5 degree Celsius control, the Emerson only 1 degree. It’s minor, but a degree Fahrenheit is about twice as precise as a degree Celsius and you lose that precision using the unit with metric units.

    • Desmond says:

      Ease of use


      Power options




      Integration with home automation systems


      Yes, I have the same problem. I just installed one in Melbourne, Australia and works fine and the only problem is it does not support our time zone…Hope the new firmware comes soon!

  11. […] Read our full Emerson Sensi review here and decide for yourself. […]

  12. […] The Emerson Sensi is far easier on the budget than most smart thermostats, but not much lighter on features. It even runs without a C-wire in many systems, making it a popular alternative for homes that lack the wiring to run some of the fancier touch-screen thermostats. […]

  13. Gene D. says:

    We are away from home for thee months during the winter. How low can the heat mode be programed for an extended time period.

    • Paul Olinski says:

      That depends on the type of heating system. For gas fired forced hot air system by Lennox they recommend not going below 55degrees or else condensation will corrode the heating chamber. The thermostat can be set below that. I haven’t tried below 50 degrees.

  14. […] there are better smart thermostats out that also happen to cost less. Those thermostats are the  Emerson Sensi and the Lux Geo, if you’re […]

  15. BernieL says:

    Is this unit compatible with a WINDOWS SMARTPHONE?
    I dislike APPLE products as they they are WAY overpriced, and Android is too “ICONY” for my tastes and a bit confusing for an “OLD DOS” nerd like me.

  16. Richard DeVries says:

    Ease of use


    Power options




    Integration with home automation systems


    I have two concerns regarding this Sensi Thermostat:
    – It can ONLY be programmed or change programs via its
    app or online access. The natural place to program is at the
    thermostat per se and not via the internet. No internet
    connection means you’re SOL in changing one’s program
    – The internet connection to Sensi is iffy and comes an goes
    – Customer service is not much help and troubles were out of box
    I recommend wifi thermostats like Lennox’s (I enjoy 1 at my cabin)

  17. […] B. Grant, Review: Emerson Sensi Wi-Fi Thermostat (1F86U-42WF), smartthermostatguide.com, May 14, […]

  18. Hari Selden says:

    The box says it does not require a “C” wire on “most” systems. My 2009 Furnace is not most systems I guess.

    Saying your product is “Universal” when it is does not work even just on the systems on Earth is deceptive advertising intended to trick consumers into buying a product that costs thousands of dollars to install.

    I am returning mine to Home Depot.

  19. Larry Bannerman says:

    Ease of use


    Power options




    Integration with home automation systems


    I originally gave these thermostats a 5 rating, but each time you change cell phone or router you face a new ordeal. I replaced my router and cell and got support to remove them from registration and since then ZERO connectivity. They have become expensive “normal” thermostats that i could have got for $8 at home depot. THINK TWICE!

  20. Paul Onley says:

    Ease of use


    Power options




    Integration with home automation systems


    Cannot be set below 50F. To access from web browser you need to subscribe to sensi manager service for $10/year/thermostat. sensi manager service would not accept my CC information. I will be buying something else, this thermostat is far too limited to be of any value.

  21. Jan W says:

    Ease of use


    Power options




    Integration with home automation systems


    Not worth the aggravation. First, the one I purchased was defective. Had to run back to Home Depot at 9pm after spending a few hours working in the heat (no thermostat=no cooling) and with tech support to make it work only to find out the unit was defective. Then the second took a while to get set up – HVAC wiring from previous thermostat was not compatible with this device – although the app said it would work fine!

    Then, after getting it all set up and running I start having issues with wifi. Inconsistent – sometimes online sometimes offline. Turns out now Sensi support is saying that wifi won’t work consistently without a C Wire. DO NOT BUY THIS PRODUCT IF YOU HAVE A HEAT ONLY, COOL ONLY OR HEAT PUMP WITHOUT A C WIRE!

    Note that most of the online documentation leads you to believe that this device works without a C Wire on “Most” units. “Designed to work with the wires you already have, 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. and Canada. A c-wire is required for heat-only, cool-only and heat pump (without aux) systems and for use with Apple HomeKit. ”

    If you look at the compatibility chart, https://sensi.emerson.com/en-us/support/how-can-i-be-sure-a-sensi-thermostat-will-work-with-my-hvac you will see a long list of incompatibility without a C wire.

    However, support will not tell you that until you’ve spent countless hours reconfiguring and even though they knew I had a heat pump. Their options now are run a c wire or buy a kit that replaces it. BTW – Search for No C Wire on their support site and you get no results. Support site is awful!

    No I have to go back to Home Depot and return the thing. No box or packaging as I threw that all away once the unit was working to provide adequate cooling.

    I’ve spent more time on trying to make this thing work that it’s worth. Should have stayed with a traditional programmable…And not Emerson!

  22. Chris says:

    Ease of use


    Power options




    Integration with home automation systems


    I’ve had mine for about a year, running on batteries and connected to my wifi. Never had to change the batteries yet. Seems your review is very off on this point.

  23. BARRY PAYNE says:

    Ease of use


    Power options




    Integration with home automation systems


    I spent a day installing the wifi w/up/down button (avoid touch screen issues) nd the o/b wire problem, HP1/HP2 selections, and other install related issues the average installer will run into is not in the manual. After getting it all to work on my own using a little trial and error, needed to connect to wifi, and of course the instructions don’t help. After emailing tech support and not getting replies I called. The girl walked me through a few steps and I was connected to the app via wifi. Why is that not in the manual? I started to wonder how to use Alexa with it and before I did I tried to go through the steps to get my wife’s iPhone connected and poof! No wifi connection. Took out batteries, nothing. Waited and hour, nothing. I believe the only way is to reboot your router. At this point I’m thinking, what if I lose power briefly like it does sometimes? I really don’t want to go through all of this. I bought an Alexa dot and it doesn’t need reconnecting after a power loss, nor does many other smart home items, but this new wifi thermostat needs special care every time. No thank you. Bought on Amazon but through a seller. Won’t take it back, wants me to contact the manufacturer. There’s a lot wrong here.

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