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Sensi Thermostat Manual 1F87U-42WF ST55

SMART THERMOSTAT  
ual Operation  
Models: 1F87U-42WF, ST55  
Version: January 2020  
©
2020 Emerson Electric Co. All rights reserved  
R-5029.  
Table of Contents  
Buttons and Icons  
Basic Functionality  
Manual Settings  
3
4
6
Menu Configurations  
Wiring Terminals  
8
9
Back of the Face Plate  
10  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
2
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  
UP ARROW BUTTON  
SCHEDULE BUTTON  
Indicates Wi-Fi connection status.  
When you turn Wireless Off on  
the thermostat, this is blank.  
Adjusts the temperature set point  
or thermostat configuration.  
Toggles the schedule On or Off.  
(The thermostat runs a program  
based on time and temperature set  
points when Schedule is On).  
CURRENT SET TEMPERATURE  
Current set temperature the  
thermostat will maintain.  
BACKLIGHT BUTTON  
Illuminates the thermostat for 10 seconds  
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.  
TIME  
MENU BUTTON  
Displays current time.  
Access thermostat configurations.  
(See page 6 for more details).  
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).  
DOWN ARROW BUTTON  
MODE BUTTON  
Adjusts the temperature set point  
or thermostat configuration.  
Switches system mode between Heat,  
Cool, Off or Aux. (Auto Mode is only  
available using the Sensi app).  
CURRENT ROOM TEMPERATURE  
BATTERY ICON  
The room temperature at the thermostat.  
When the bars get low, remember to  
change the 2 AA Alkaline batteries in  
the back of the thermostat face plate.  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
3
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.  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
4
BASIC FUNCTIONALITY  
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:  
1. Press “Menu”  
2. Press “Next” until you come to “Fn Setup”.  
3. Use the up arrow button to toggle the percentage you’d like the fan to run each hour.  
4. 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:  
1. Press “Menu”.  
2. 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”.  
3
4
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
5
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.  
1. Turn Wi-Fi Off. (Refer to section “Turn Wi-Fi Off” on page 4).  
2. Press and hold the “Schedule” button.  
3. 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.  
4. 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.)  
1. Turn Wi-Fi Off. (Refer to section “Turn Wi-Fi Off” on page 4).  
2. Use the “Mode” button to set which type of schedule it will be: Heat or Cool.  
3
. 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.  
4. Press “Next”  
5. You will see a large number in the middle of the screen. This refers to your set point.  
a. The time will be flashing at the top of the screen. Adjust the time of  
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.  
6. Press “Exit”.  
7. Make sure “Schedule” is set to “On” on the thermostat.  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
6
MANUAL SETTINGS  
Example Schedule  
If you need to keep track of your time and temperature set points, use this table.  
SAMPLE SCHEDULE  
PERIOD  
DAILY START TIME  
DAILY TEMP  
1
st  
6:00 am  
8:00 am  
5:00 pm  
10:00 pm  
6:00 am  
8:00 am  
5:00 pm  
10:00 pm  
70° F  
62° F  
70° F  
62° F  
78° F  
85° F  
78° F  
82° F  
2
3
nd  
Heat  
rd  
4
th  
1
st  
2
nd  
rd  
Cool  
3
4
th  
COMPLETE YOUR SCHEDULE  
PERIOD  
DAILY START TIME  
DAILY TEMP  
1
st  
6:00 am  
8:00 am  
5:00 pm  
10:00 pm  
6:00 am  
8:00 am  
5:00 pm  
10:00 pm  
2
nd  
rd  
Heat  
Cool  
3
4
th  
1
st  
2
nd  
rd  
3
4
th  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
7
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  
Display Code  
Menu item  
Default  
Options  
Connect  
Wireless Setup  
F
Connects Thermostat to WiꢀFi network  
F
C
Fahrenheit or Celsius  
AC1 –  
Conventional Cooling 1  
Single Stage)  
(
Outdoor Equipment  
Configuration  
AC2–  
Conventional Cooling 2  
(TwoꢀStage)  
AC2  
Cooling or heat pumps  
HP1 –  
HP2–  
Heat Pump 1 (Single Stage)  
Heat Pump 2 (TwoꢀStage)  
AC0–  
EL1–  
No Cooling  
Electric 1 (Single Stage)  
EL2–  
FAn  
GA1  
Electric 2 (TwoꢀStage)  
Indoor Equipment  
Configuration  
EL2  
O
For Gas or Electric Heat  
Gas 1 (Single Stage)  
Gas 2 (TwoꢀStage)  
GA2  
O
Reversing Valve Position Selects “O” or  
B
2
B” Setting For Heat Pumps Only  
Fn  
Circulating Fan  
OFF  
OFF  
Off/10% – 100% (5% increments)  
Humidification  
Add Accessory  
Humidification  
Set Point  
H AA  
Off/On  
H SP  
OFF  
Off/5% – 50% (5% increments)  
Od/Oc  
Od – Optimal dehumidification  
(Overcool to dehumidify)  
Oc – Optimal comfort  
Dehumidification  
Add Accessory  
dH AA  
Od  
(
Wired dehumidification)  
Dehumidification  
Set Point  
dH SP  
OFF  
ON  
Off/40% – 95% (5% increments)  
Wireless Radio  
Turns WiꢀFi Radio On/Off  
Off/On  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
8
WIRING TERMINALS  
See below for definitions of the wiring terminals on the sub-base of the thermostat.  
Terminal outputs and wiring diagrams  
TERMINAL LABEL  
DEFINITION  
RH*  
RC*  
C**  
G
Power for heating, 24V  
Power for cooling, 24V  
Common wire, 24V  
Indoor blower (fan)  
Y
First outdoor stage cooling on conventional systems or first heat and cool on heat pump systems  
Second outdoor stage cooling on conventional systems or second heat and  
cool on two stage heat pump systems or humidifier  
Y2/*  
W/E  
First indoor stage heat on conventional systems or first stage auxiliary/emergency heat on heat pump systems  
Second indoor stage heat on conventional systems or second stage auxiliary/  
emergency heat on heat pump systems or dehumidifier  
W2/*  
O/B  
L
Changeover (reverse valve) connection for heat pump or zone panel systems  
Heat Pump system, “L” wire connection  
*
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.  
Does Wire Color Correspond to the Thermostat  
Terminals?  
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.  
Sensi Smart Thermostat | MANUAL OPERATION GUIDE  
9