Shut off power to your thermostat at the circuit breaker.
Remove your old thermostat's faceplate and set it aside.
Take a picture of your existing thermostat wiring for reference.
Visit Sensi's site to see if your existing thermostat wiring is compatible.
You can use the picture you just took to confirm what wires you have.
If your thermostat wires aren't already labeled, use the included stickers to tag each one.
Disconnect your thermostat wires from your old thermostat.
If your baseplate looks like mine, you'll need a Phillips-head screwdriver to loosen the wires before removing them.
Unscrew your old thermostat base plate from the wall.
If your thermostat wires run the risk of falling behind your wall, use a pen or pencil as a placeholder if you need to step away.
Feed the wires through the Sensi thermostat's baseplate and use the included hardware to attach it to the wall.
Note: You may need to drill new holes in the wall to match the Sensi baseplate. I got lucky with the alignment of the original holes and was able to skip that step.
Use your newly labeled thermostat wires as a guide and connect them to the appropriate port.
Tighten the screws to secure the wires in place.
Line up the faceplate with the baseplate and snap it on.
Turn power back on at your circuit breaker.
Download the Sensi app for Android or iOS.
Select "Create Account."
Add your personal details to make your Sensi account.
Agree to the Terms of Service.
Select "Connect thermostat to Wi-Fi."
Press "Menu" and then "Connect" on your thermostat in quick succession.
Hit the arrow in the app to advance to the next step.
Go to your phone's settings and select the Sensi Wi-Fi network.
If it prompts you for a password, enter the Sensi security code shown on the card that came with your purchase.
Note: You can also find the security code on the back of your thermostat.
Return to the app and wait for it to advance to the next screen.
There you'll select your Wi-Fi network from a list and enter your password to connect.
Give the app a few seconds to connect.
Here's where you name your thermostat and enter your address and time zone.
This message will appear when you've successfully installed and connected your Sensi thermostat to the app.
Now you can start controlling your thermostat from your phone.