Emerson ST76 Touch 2 Smart Thermostat User Manual

The Sensi Smart Thermostat is a Wi-Fi-enabled device. To install and configure your thermostat correctly, you must use the Sensi app. To start the installation process, download the Sensi app to your smartphone or tablet. It is a free download. The Sensi app requires the following Operating System (OS) software to download:

Emerson ST76 Touch 2 Smart Thermostat-1

Create an account

When you download the Sensi app, you will be prompted to create an account. This is required to access your thermostat remotely and use all the features Sensi offers. Use a valid email address and a password of your choosing to create an account. Remember this email address and password. Your Sensi thermostat will be linked to this email address once it is registered.

INSTALLING THE SENSI THERMOSTAT

STEP 1
Add your thermostat to the Sensi app

Installation

Once you have downloaded the Sensi app, and have created an account, you are ready to install the thermostat to your wall and connect it to Wi-Fi. If no thermostats are registered yet, tap the “+” sign to add a thermostat.
Then, choose which thermostat you purchased.

1F96U-42WF series
ST76 series
Note: You can check your model number on the back of the thermostat faceplate.

STEP 2
Is your Sensi thermostat already on your wall?

NEW INSTALLATION
After choosing your Sensi model, tap New Installation. Next, select whether your thermostat Is Currently Mounted or Not Mounted on the wall.
NOT MOUNTED
This option walks you through a full step-by-step installation process. You will identify which wires are on your original thermostat, how to label them for Sensi, how to connect your wires, and how to connect to Wi-Fi.
If you did not have this thermostat professionally installed, choose this option. It will ensure that your thermostat is properly wired and configured to work with your HVAC system.
IS CURRENTLY MOUNTED
This option asks you to identify the wires already installed on your Sensi Touch 2 to ensure that your HVAC settings are correct and connects you to Wi-Fi. If you had a professional technician install your thermostat, choose this option and skip to STEP 5b.
Pro Tip:
If you are DIYing your installation, always choose Not Mounted to make sure your thermostat is wired and configured correctly.
GATHER TOOLS AND PACKAGE CONTENTS
Gather all the necessary tools for installation.
TURN OFF POWER
Turn off the power to your heating and air conditioning system before handling your thermostat wires.

STEP 3
Remove the old thermostat from your wall

REMOVE OLD THERMOSTAT COVER
Remove the cover using a screwdriver or by pushing the pressure latch.
Some covers pull off while others need to be released using a screwdriver.
PHOTOGRAPH YOUR WIRING
THIS IS IMPORTANT. The Sensi app will prompt you to take a picture of your existing thermostat and old wiring in case you need it later.
This can be helpful for troubleshooting with our technical support team, if necessary. The picture you take will be saved to your camera roll or photo gallery.
THROW AWAY ANY JUMPER WIRES
Sensi has a jumper wire built into it, and you will not need any jumper wires from your old unit.
CHOOSE WIRE TERMINALS
Choose the terminal labels that have wires attached to them on your old thermostat. The app will tell you if you have a valid configuration.
If you are getting an invalid configuration message you can learn more about compatibility at sensi.emerson.com/system.
Sensi Touch 2 requires a c-wire.
For more information, visit sensi.emerson.com/en-us/support/c-wire.
FURNACE TYPE
Select what type of system you have.
LABEL YOUR WIRES
Before you disconnect your wires, label your wires using the label stickers provided one wire at a time.
DISCONNECT WIRES AND REMOVE BASE
After all of your wires are labeled, remove the old thermostat base from the wall.

STEP 4
Secure your new thermostat base to the wall

INSTALL SENSI BASE
Use the mounting screws provided and secure the Sensi base to the wall.

STEP 5a – NOT MOUNTED
Connect the wiring and thermostat cover

CONNECT THE WIRES
Once the Sensi base is mounted and secured on the wall, insert the wires into the terminals. Simply push the wires into the terminal slots.
ATTACH THERMOSTAT COVER
Push the thermostat cover onto the base.
TURN ON POWER
Turn the power to your system back on.

STEP 5b – IS CURRENTLY MOUNTED
Identify the wires already installed to correctly configure the thermostat for your system type
Emerson ST76 Touch 2 Smart Thermostat-11

TURN OFF POWER
Turn off power to your heating and air conditioning system before handling your thermostat wires.
REMOVE THERMOSTAT COVER
Grab the thermostat with both hands and pull straight toward you. The cover will detach from the base.
IDENTIFY WIRES
Choose the labels on your thermostat base that have wires attached to them.
The Sensi Touch 2 requires a c-wire, so make sure one is installed.
SELECT FURNACE TYPE
Identify which type of heating source you have.
ATTACH THERMOSTAT COVER
Push the thermostat cover onto the base.
TURN ON POWER
Turn the power to your system back on.

STEP 6
Connecting to Wi-Fi and registering your thermostat

CONNECTING TO WI-FI
After wiring and installing the thermostat, you’re ready to connect to Wi-Fi.
Pro Tip:
If the thermostat screen is not turning on after wiring installation, you may have an issue with your c-wire connection. The c-wire powers the thermostat, and it won’t turn on without it. See the troubleshooting section on pg. 9 for more information.
WI-FI SETUP
On the thermostat, press Menu in the top left corner and then Wi-Fi. Tap Connect.
SCAN QR CODE
In the app, scan the QR code on your Sensi Touch 2 screen. Bluetooth technology will help you connect to Wi-Fi. This will require Bluetooth permissions on your phone. You can turn on Bluetooth in your phone’s settings. If you’re having trouble scanning, tap Use Security PIN to manually enter the code on your touchscreen.
SELECT YOUR WI-FI NETWORK
In the list of available networks, select your home Wi-Fi network and then enter your home Wi-Fi network password.
Pro Tip:
Sensi is only compatible with 2.4GHz networks. If your network does not show up in the list, it is either hidden or not compatible with Sensi.
NAME THERMOSTAT
You can select a name or choose a custom name for your thermostat. Press Next to continue.
REGISTER THERMOSTAT
After successfully connecting Sensi, the app will prompt you to register the thermostat. You can either choose the Locate Me option or fill in your street address, city, state, ZIP code, country and time zone manually. Press Next to continue.
CONTRACTOR INFORMATION (OPTIONAL)
If a contractor professionally installed your thermostat and is registered as a Sensi partner, they have the option to input their phone number here. If there is not a registered number available, simply hit Next to continue.
START USING SENSI
Congratulations on successfully installing Sensi. Press Start Using Sensi to open the main screen of the app.

TROUBLESHOOTING

Why isn’t my heating/cooling turning on?

Ensure that there is power to your HVAC system and there is no error code on your control board indicating a system issue.
- If there is an error code or no power to your system, contact an HVAC professional to service your equipment.
Reset breakers.
Make sure the furnace/air handler door compartments are securely screwed down and closed. If the door panels are not secure, the system will not start.
Secure wire connections.
- If you pull on a wire, it should not come out. Make sure the wire is all the way down and seated in the thermostat terminals. If you aren’t sure, push the paddle down and pull the wire out. Then, try to push it back into the terminal for a better fit.
Ensure the thermostat is wired correctly by following the instructions in the Sensi app.
- You can also try to reinstall your original thermostat to make sure there is not an HVAC system issue that is preventing the system from turning on. If your heating/cooling doesn’t come on with the original thermostat, you may need to contact a professional technician to service your equipment.

Connecting to Wi-Fi Troubleshooting

If you’re having trouble connecting to Wi-Fi, here are some tips to try:

Make sure the Sensi app is up-to-date and running the latest version available in your app store.
Reboot your smartphone.
Reboot your router by unplugging it from the wall for a few minutes and then plugging it back in.
After your router reboots, and your Wi-Fi network has internet access again, make sure that your phone is connected to your 2.4GHz Wi-Fi network.
If you’re on an iPhone, make sure Keychain is On, and Home Data is allowed for the Sensi app.
If you’re on an Android, go into your phone’s Advanced Wi-Fi Settings and turn off the “Switch to mobile data” feature. (Depending on your Android, it may be called “Smart Network Switch” or “Avoid poor connections.”)
It may be easier to just turn “Mobile Data” off completely for setup. You can find this in your Connection settings.
Try another smartphone or tablet. Simply download the Sensi app and sign into the app using the email address and password you used when you created your account.

Reconnecting to Wi-Fi

If you replaced your router or changed your Wi-Fi network password, you will need to reconnect your thermostat to Wi-Fi. This is different depending on what smart device you are using. Please see our support article for more information on how to reconnect.sensi.emerson.com/en-us/support/reconnecting-Sensi-thermostat-to-wifi.

Blank or flashing display

If you installed a Sensi Touch Smart Thermostat, but the touchscreen is still blank or only flashes after completing all the steps in the Sensi app, then most likely the thermostat is not receiving enough power from your system to turn on or stay on continuously.
Sensi Touch requires a “C” wire to power the thermostat. Sensi does have a battery-powered light in the sub-base for installation, but that light will only last for about an hour, and is not an indicator that there is power to the thermostat.
I DON’T HAVE A WIRE IN THE “C” TERMINAL.
Sensi requires a “C” wire. If you don’t have a wire in the “C” terminal, check out our “C” wire videos for DIY installation at sensi.emerson.com/en-us/c-wire.
If you are installing Sensi to a heat-only system, you may be able to install an external transformer. Learn more about that option by searching “external transformer” on our support site at sensi.emerson.com/en-us/support.
I HAVE A WIRE IN THE “C” TERMINAL.
Did you DIY this c-wire connection? If so, make sure that this wire is connected to “C” terminal at the thermostat and at your system.

Go down to your indoor HVAC unit furnace/air handler, reveal your system’s control board and trace the c-wire at the thermostat to ensure that it is securely connected to the “C” terminal at the system control board. If you haven’t already, it may help to watch one of the c-wire videos to see how to access the control board.
Gently tug the c-wire at the system control board to ensure that it is screwed into the terminal securely.
Gently tug all the wires at the thermostat to ensure that they are secure in the terminal block on the sub-base.
Do you have a voltmeter? Set your voltmeter to AC and measure the voltage between RH (or RC) and C at the thermostat to ensure that you have between 20–30VAC at the thermostat. If you have less than 20VAC, the thermostat will not turn on.
Are your breakers on? You turned your power off for installation. Make sure the power is turned on. You may want to try resetting them if they’re already turned on.

HVAC configuration menu
If you chose the option “No, it needs to be installed”and walked through the installation process on the Sensi app, the app should have correctly configured your thermostat for your system type. 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
Menu item	Description	Options
Outdoor Equipment	Select AC or Heat Pump equipment, as well as the number of stages. Set this to AC1 for single-stage systems or HP1 or HP2 for single or multi-stage heat pumps	AC1/AC2/HP1/ HP2/None
Indoor Equipment	Select whether the equipment is an electric or gas furnace or fan only. Set this to EL1 for single- stage electric or GA1 or GA2 for single or multi-stage gas systems.	GA1/GA2/EL1/ EL2/Fan
Reversing Valve Position	When configured for O, the reversing valve is energized in cooling. This will cover most applications. Some manufacturers, such as Rheem or Rhudd, use the B terminal, which would energize in heating. For three-wire zone hydronic systems, set this to Z.	O/B/6/None
Additional Accessories
Humidifier (wired to thermostat)	If a humidifier is wired to the thermostat, change the Humidifier setting to YES.	Yes/No
Dehumidifier (wired to thermostat)	If a dehumidifier is wired to the thermostat, change the Dehumidifier setting to YES.	Yes/No

Accessing your Sensi thermostat from other devices
When you log into your Sensi account with your email address and password, the app will be able to control all the thermostats registered to your Sensi account. If you give someone else your email address and password to your Sensi account, they will be able to log in and control any thermostats registered to that account. You can change your email address and password from inside the app. Be aware of this when giving out your information. There is no limit to the number of devices that can access the thermostat.
Forgot password
If you forgot the password to your Sensi account, click on “Forgot Password” on the login screen of the Sensi app. A temporary password will be sent to the email address that you use to login.

Installing multiple thermostats

If you are installing more than one thermostat, follow the same installation process in the Sensi app. Once you have one thermostat installed, open the Sensi app on your phone. At the main screen, tap the + sign to add another thermostat to your account.
Accessing account information
You can use the Account area to access your email preferences and change your account information and email address associated with your Sensi.
For iOS: Tap the person icon in the upper right-hand corner.
For Android: Tap the three dots in
the upper right-hand corner.

Technical support

For problems connecting your Sensi thermostat, call or email the Sensi Technical Support team, and they will be happy to help you or your contractor walk through any steps needed to troubleshoot the Sensi thermostat. sensi.emerson.com/en-us/support (888) 605.7131 [email protected]

NOTES

CONVENTIONAL SINGLE-STAGE OR MULTI-STAGE SYSTEMS WITH NO HEAT PUMP

Emerson ST76 Touch 2 Smart Thermostat-18

HEAT PUMP SYSTEMS Emerson ST76 Touch 2 Smart Thermostat-19

ACCESSORY DEVICE

2-Wire accessory
device has it’s own power source to turn the unit on.Set the switch on the back of the thermostat to “Accessory.”
1-Wire accessory
The device pulls power from the HVAC system. Set the switch on the back of the thermostat to “System.”

Emerson ST76 Touch 2 Smart Thermostat User Manual