I have never grown up in a house that didn’t have a working furnace or air conditioner. In fact, whenever our central air conditioner or furnace stopped working, we would immediately call an HVAC technician to drive out to our house and repair it. It is hard for me to even imagine that days before electricity and modern machinery. However, I like reading books, and I wanted to understand how the generations before us were able to heat or cool their houses without the use of modern HVAC units. First of all, you should be aware that the generations before us didn’t have a need for modern air conditioners. That is because the generations before us were much wiser in the ways that they built their houses. Typically, older houses were built partially underground or ever in the woods in order to ensure that the air would be cooler. By orienting the porch, house, and windows to the South, they would ensure that there was cool air in their house without an air conditioner. However, they still needed to have heat, but furnaces were definitely not an option. However, for thousands of years, people have been relying upon fireplaces and wood stoves to provide heat for their homes, and that tradition has still carried on into some houses today. Wood-burning HVAC units are very efficient, and they are cheaper than the modern furnaces that we have. We should be very careful about labeling these people as primitive for not having air conditioners and furnaces. These people understood a lot about hard work and proper home-building techniques that we can learn a lot about.