Emerson Sensi Smart Thermostat Manual – Sen|Si 1F87U-42WF, ST55
BUTTONS AND ICONS
The Sensi Smart Thermostat can be operated through Wi-Fi using the Sensi app or it can be operated at the actual wall
unit. Advanced features such as thermostat settings, scheduling and email alerts are only available through the Sensi app.
WI-FI STATUS ICON
- Indicates Wi-Fi connection status.
When you turn Wireless Off on
the thermostat, this is blank. - BACKLIGHT BUTTON
Illuminates the thermostat for 10 seconds - TIME Displays current time.
- KEYPAD LOCKOUT ICON
This icon indicates the thermostat
is locked out. No changes can be
made at the thermostat. (Can only
be enabled from the Sensi app). - BATTERY ICON
When the bars get low, remember to
change the 2 AA Alkaline batteries in
the back of the thermostat face plate. - UP ARROW BUTTON
Adjusts the temperature set point
or thermostat configuration. - CURRENT SET TEMPERATURE
Current set temperature the
thermostat will maintain. - MENU BUTTON
Access thermostat configurations.
(See page 6 for more details). - DOWN ARROW BUTTON
Adjusts the temperature set point
or thermostat configuration. - CURRENT ROOM TEMPERATURE
The room temperature at the thermostat. - SCHEDULE BUTTON
Toggles the schedule On or Off.
(The thermostat runs a program
based on time and temperature set
points when Schedule is On). - FAN BUTTON
Switches fan mode from Auto
or On. Leave the fan mode on
Auto to allow the thermostat to
control the fan as necessary. - MODE BUTTON
Switches system mode between Heat,
Cool, Off or Aux. (Auto Mode is only
available using the Sensi app).
BASIC FUNCTIONALITY
Switching System Mode
Press the “Mode” button to switch between all available system mode settings. When
the Mode is “Off” the thermostat will not bring on your heating or cooling systems.
Fan Mode
If you want to circulate the indoor blower, you can switch Fan to “On.” Turn the
Fan back to “Auto” when you want the thermostat to control your indoor blower
as necessary. Leaving the Fan in “On” will run your blower continuously
Holding One Temperature
If you want to hold one temperature, turn Schedule “Off.” Then, adjust the
set point using the up and down arrow buttons. The thermostat will hold
this temperature, in the set Mode, until you turn Schedule back “On” or until
you adjust the set point again using the up and down arrow buttons.
Temporary Hold
When your schedule is set to “On,” your Sensi thermostat controls your home based on
the time and temperature settings in the current schedule. To temporarily change your
temperature use the up and down arrows in the app or on the thermostat. Your Sensi
thermostat will display “Temporarily Set To” on the thermostat and will hold your new
temperature until the next scheduled set point with a minimum hold time of two hours.
Circulating Fan
If you want to circulate the air in your home using your indoor blower fan, you can set
this feature in the app or at the thermostat. A percentage is selected to indicate how
often the fan should run each hour, You can set 5% increments from 10% – 100%.
EXAMPLE:
If you set the Circulating Fan to 50%, the fan will run 30 minutes every hour.
If any heat/cool cycles occur during the hour, their runtime
is subtracted from the overall fan run time.
Setting the feature from the
thermostat:
- Press “Menu”
- Press “Next” until you come to “Fn Setup”.
- Use the up arrow button to toggle the percentage you’d like the fan to run each hour.
- Press “Exit”
Turn Wi-Fi Off
If connecting to Wi-Fi is not an option, you can turn off Wi-Fi on the thermostat
and manually set a time and a schedule from the wall unit. To turn off Wi-Fi:
- Press “Menu”.
- Press “Next” until you see “Wireless (Setup)” at the top of the screen.
“On” should be flashing at the top. - Use the up or down arrow button to change it to “Off”.
- Press “Exit”.
MANUAL SETTINGS
Setting the Time Manually
When connecting the thermostat to Wi-Fi, the time will sync automatically. If not
connecting to Wi-Fi, follow these steps to set the time at the thermostat.
- Turn Wi-Fi Off. (Refer to section “Turn Wi-Fi Off” on page 4).
- Press and hold the “Schedule” button.
- The screen will go blank and the time will start flashing at the top. Use the up and down
arrow buttons to rotate through the times until you get to the appropriate time of day. - Press “Exit”.
Setting a Schedule
When connecting the thermostat to Wi-Fi, the schedule is
programmed based on time and temperature set points from the
Sensi app. If you are not connecting to Wi-Fi, follow these steps
to set a basic 7 day schedule with 4 mandatory set points.
(More robust scheduling options are only available through the Sensi app.)
- Turn Wi-Fi Off. (Refer to section “Turn Wi-Fi Off” on page 4).
- Use the “Mode” button to set which type of schedule it will be: Heat or Cool.
- Press and hold the “Schedule” button, until you see the time flash at the top of the screen
a. Adjust the time on the thermostat if needed, using the up and down arrow buttons. - Press “Next”
- You will see a large number in the middle of the screen. This refers to your set point.
the first set point using the up and down arrow buttons.
b. Press “Next”. The set point will be flashing. Adjust the set
point using the up and down arrow buttons.
c. Press “Next”.
d. Repeat steps a-c for the second, third and fourth set points. - Press “Exit”.
- Make sure “Schedule” is set to “On” on the thermostat.
Example Schedule
If you need to keep track of your time and temperature set points, use this table.
SAMPLE SCHEDULE
COMPLETE YOUR SCHEDULE
MENU CONFIGURATIONS
Pressing “Menu” at the thermostat allows you to change a series of settings to customize the thermostat
for your specific system. Refer to the chart below for a complete listing of thermostat configurations
and what they stand for. If you are installing the thermostat on the wall for the first time, we highly
recommend that you download the Sensi app and follow the installation instructions.
However, if you are experiencing an issue or you want to check your system configurations, you
can manually configure your thermostat as well. Learn more about how to properly configure your
thermostat by searching “configure” on our support site at sensi.emerson.com/en-us/support.
CONFIGURATION MENU ITEMS REFERENCE
See below for definitions of the wiring terminals on the sub-base of the thermostat.
* If the old thermostat has separate RC and RH wires coming out of the wall, clip the RC/
RH jumper on the back of the thermostat above the battery compartment.
**The common wire could be labeled “C” on your old thermostat, or it could be labeled “B”
or “X.” Please refer to the owner’s manual of your old thermostat for clarification.
Wire color does not always correspond to the thermostat letters. A white wire may be attached to the “W” terminal
on the old thermostat, or it may be attached to a different terminal with a different letter. Be sure to take a photo
of the old thermostat that shows the wire colors and terminal letters before labeling and removing any wires.
Below is a picture of the back of the Sensi thermostat face plate. The back plate shows the jumper
wires, battery compartment, and some useful information about your thermostat.
- SENSI SECURITY CODE
Necessary for connecting to Wi-Fi. Also found
on the Welcome Guide in the packaging. - MODEL NUMBER
Illustrates whether you purchased the
professional or the DIY model. - APPLE HOMEKIT CODE
The 8 digit code used to add Sensi Thermostat to Apple HomeKit.. - RC/RH INTERNAL JUMPER WIRE
Only clip this if you have separate RC and RH
transformers coming out of the wall. - BATTERY COMPARTMENT
Two AA Alkaline batteries are used for back-up purposes. When
you see the battery indicator bar on the thermostat display reach
3 bars, replace these batteries to maintain Wi-Fi connectivity. - DATE CODE
When your thermostat was manufactured. - MAC ID
Unique number that identifies the thermostat.
Sensi Smart Thermostat | MANUAL OPERATION GUIDE
FAQs
How do I change the batteries?
The batteries are located in the back of the thermostat. Remove the face plate by prying it up with a small screwdriver.
How do I set up my thermostat for Wi-Fi?
The Sensi app will guide you through the process. First, make sure your thermostat is powered on and connected to your home Wi-Fi network. Next, open the Sensi app and select “Add Thermostat” from the menu. Follow the on-screen instructions to complete setup.
My thermostat is not connecting to my Wi-Fi network. What should I do?
Make sure your thermostat is powered on and connected to your home Wi-Fi network. If it is, open the Sensi app and select “Add Thermostat” from the menu. Follow the on-screen instructions to complete setup. If you still have problems, contact Emerson at 1-800-654-3593 or www.emersonclimate.com/support .
How do I change my Wi-Fi network name or password?
Open your thermostat’s settings by tapping Menu > Settings > Network Setup > Network Setup > Change Network Name or Change Password . You can also change these settings through your home Wi-Fi router’s settings page (e.g., http://192.168.1.1).
My schedule is not working properly; what should I do?
Make sure you have enabled Schedules in your thermostat’s settings (see page 6 for more details). If you have enabled Schedules, make sure you have created at least one schedule in the Sensi app (see page 6 for more details). If you have created a schedule, make sure that all of its conditions are set correctly (see page 6 for more details). If all of these conditions are correct, then try deleting and re-creating your schedule (see page 6 for more details). If none of these steps work, contact Emerson at 1-800-654-3593 or www.emersonclimate.com/support .
What is the difference between the ‘pro’ kit and the ‘diy’ kit?
Sensi Support told me that only the professional HomeKit versions have a circulating fan feature. This was important for me because I live in a two story house and in summer the downstairs will be cool, while the upstairs is hot. The circulating fan will move cool air upstairs even when the AC unit is not running. Here is their exact message that was sent to me “Thank you for contacting Sensi Support. The circulating fan feature is only available on professional HomeKit models: 1F87U-42WF and 1F95U-42WF.
Which model allows you to control the temperature differential or cycle rate?
ST55 does, but I do not utilize.
can it control AC and heat
Yes it does control AC and heat. We love ours and we have a few friends & family who also have purchased one and are very happy.
Does anyone have issues with thermostat batteries. The most i get out a set of AA is 2 weeks?
The WiFi is draining your batteries AND you do not have the C wire connected. The C wire (blue) is 24VAC (one leg of it). If you turn off WiFi, the thermo will run for months on the batt as a dumb thermo and NO schedule. If you don’t need WiFi, get the non-WiFi version which has the schedule built into the memory of the thermo. What Emerson needs is a model with WiFi AND the schedule in the device’s memory. The WiFi is hokey because if WiFi is “lost”, there is no access to the schedule! AND I HAVE lost WiFi in the middle of winter and woke up in a very chilly house at 3AM.
Exactly how is the fan only run time implemented?
Not 100% sure if the question, but I believe it’s in the app settings where you can set the fan to run every so often for a set period of time just to circulate the air.
Does this work with a dual fuel system? Heat pump with gas furnace that kicks on when outside temp drops below 40 degrees.
It should Yes
Does this device have a microphone or does it only work with other voice activated devices because of the microphones in those devices?
Only works with other voice activated devices.
Can this replace an existing line voltage Honeywell unit without a C-wire?
It needs a c wire for sure.
Can i monitor multiple t-stats. I have 134 homes I would like to install these in.
The maker offers a paid subscription ($10/thermostat/year) service where you can monitor multiple thermostats from a browser.
Does it work with samsung smartthings hub?
I know it does with Alexa
what is the difference between the 1f87u-42wf and the 1f86u-42wf?
The 1F87U-42WF model of the Sensi Thermostat is HomeKit compatible along with the Circulating Fan feature. The 1F86U-42WF model of Sensi is not compatible with HomeKit or the Circulating Fan feature. The functionality of both are the same.
