I've been electrifying the heating of our house bit by bit and I'm probably in the target market for your product. The big killer for direct-to-consumer here is that the refrigerants used are environmentally hazardous and most of them are greenhouse gas producers. Making it so that you don't need a licensed professional (who will charge you an arm and a leg for something that should be simple and end-user safe) would go a long way to drive adoption.

What refrigerant are you using?

Will your device require internet access? (if so it is a non-starter for me, I don't want any of my appliances connected to the internet and to have some stupid service grafted on).