I recently tried to connect to my Sensi Touch Smart thermostat to WiFi, and I ran into a lot of issues getting it to work. Sensi’s support pages were helpful for general guidance, but they could benefit from more detail and explanation. Hopefully this post will help save somebody else some headaches.
Below are some steps to follow after downloading and signing in to the Sensi mobile app. The app has a straightfoward flow in the user interface; the WiFi connectivity is the harder part. Your specifics may vary, but the general principles should be the same.
Check Your Phone’s Wifi and Network Settings
Connecting the Sensi thermostat to WiFi first requires connecting your phone to Sensi’s local WiFi. This connection doesn’t have internet access, but is required for setup. Phones often have settings that will auto-connect to different WiFi networks under various conditions. These are normally nice features, but they kind of get in our way here.
Android phones will often warn you about the internet quality when you try to connect to Sensi’s WiFi for the first time. Make sure you allow the connection and check the box to prevent it from asking again.
Here are some other settings to try in order to force your phone to connect to Sensi’s local WiFi:
Turn off mobile data.
Turn off the auto-connect feature of your home WiFi connection.
If you’re using a VPN, disable it.
After toggling these settings, try connecting to the WiFi. If you’re still having problems, you may have another issue that needs resolving.
Force Sensi Touch Smart Thermostat to Connect to WiFi on 2.4 GHz
You may need to set up a dedicated 2.4 GHz WiFi connection for your thermostat to connect to. Sensi thermostats use an 802.11n 2.4 GHz Wi-Fi radio. A lot of modern devices run on the 5 GHz band, and many routers are dual band. For the Sensi thermostat, the trouble connecing comes when both frequency bands have the same SSID (name).
There are a couple solutions to this problem.
You can set up a Guest SSID under a different name that runs on 2.4 GHz.
You can also configure your network to have different SSID names for the 2 different bands.
Personally, I went with the Guest SSID option. It was easy and avoided having to reconnect other devices.
Your router should have configuration information on it, including an IP address you can navigate to in your web browser. This web page will allow you to configure your network settings. For AT&T, it was as simple as Home Network -> Wi-Fi -> Guest SSID Enable -> Pick a Guest Network Name/Password.
This new guest network should show up under available WiFi networks, and you should select it when choosing which network the Sensi Touch Smart thermostat should connect to.