A DIY 3D printed window heat exchanger that costs just $30 to build. It efficiently heats and dehumidifies your home for a fraction of the cost of traditional systems.

DIY site If you've got a water well full of cool water, you can take advantage of that coolness to build a heat exchanger to air condition your home. Skip to Main Content ...

You could also use an actual heat exchanger designed to cool a computer CPU, or an inexpensive automotive transmission cooler There are plenty of videos of these types of DIY air conditioners.