Last summer, I visited my aunt, and the best part about being there, other than spending time with them, was riding the horses since they live on a ranch. One cold afternoon while I was going through books in their mini library, I came across a book on commercial air conditioning. The book’s author is a certified air conditioning professional with a wealth of over sixty years of experience. He lays down the evolution of HVAC systems. It is hard to imagine that a steam furnace was once a popular heating option, and some were powered by burning wood. Some of the old heating devices were very noisy, like something like an electric heat pump that we have now that produces minimal noise. It was also hard to achieve the desired temperature because they did not have the kind of temperature regulators like we do now. In today’s world, you can easily program your preferred temperature settings, or better yet, an innovative and digital thermostat can ‘learn’ your temperature preferences at different times and program itself. The type of a/c setup done nowadays is to maximize indoor comfort. The AC filter has also evolved; we now have a HEPA filter, which is one of the latest in the market, and it does wonder when it comes to improving air quality. The following day, my aunt called the air conditioning company because she needed their quality AC service. In the afternoon, the cooling expert arrived to do the maintenance. The air conditioning technician also informed us that the required ductwork cleaning before it started affected the indoor comfort of the house. I also engaged the tech with some questions about things I did not understand when I was reading.