how does this work? I want it installed in a home I am not living in

This sensor needs to be used with a compatible Sensaphone remote monitoring system. Once installed you program the system to send an alert or make a phone call (depending on the model of system) if a temperature limit is met. If you don’t already have a Sensaphone system or plan on purchasing a complete system this device will not work for you. If you only wish to monitor temperature and receive a notification if a temperature condition is met we would suggest looking at the WIRELESS-ALERT-T from Lascar. It is much less expensive and very easy to use. You connect to it using a free app on your mobile device. The module connects to your existing WIFI network and sends an email alert in the event of a temperature excursion.

Here is a link to it - https://microdaq.com/lascar-wireless-alert-temperature-monitor.php