INSTEON Thermostat Adapter

The INSTEON Thermostat Adapter (available for purchase here) connects to the Venstar T1700, T1800, and T1900 thermostats. The adapter draws power from the thermostat itself, and is an RF based product, so you'll need at least one Access Point for it to work correctly. The thermostat How-To describes basic operation of thermostats from Indigo, and this forum has a great series of posts regarding usage of the adapter from Indigo.