If you live in a dry climate, a humidistat is pretty straightforward; it just turns a humidifier on and off. That's about as simple as it gets. If you are in a humid climate, some people have taken to wiring in humidistats as dehumidistats to help control humidity when they are away. The first thing […]

If you went to school and learned the “gas laws” early on, you probably thought it seemed LAME. Then, later, things like mass flow rates, airflow conversions, and compression ratios seemed HARD. Well… It's because HVAC is hard if you don't understand the concepts behind the gas laws, even if you never learn to do […]

I was listening to someone talk about air relative humidity the other day while looking at a psychrometric chart, and he commented that the chart ends down at freezing (32°F) because “all the water freezes out of the air at that point.” I think I made this Jed Clampett face: The psychrometric chart is designed […]