Indigo 7 plugin for Mr.Slim Heatpumps powered by Red Link along with other Honeywell TCC WiFi thermostats.
The Mr.Slim support requires the Wireless Remote Controller and Reciever Kit - MHK1. You can buy one from https://www.amazon.com/Wireless-Remote-Controller-Reciever-Kit/dp/B008MB3UM4.