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 […]

The most common method to defrost appropriately in refrigeration involves both time for initiation and a combination of time and temperature for defrost termination (ending defrost). But why can't we just use temperature or time alone? (You may wonder.) Imagine a common freezer with a designed box temperature of -10°F and a coil temperature of […]

This gas furnace maintenance procedure in this article was developed by Michael Housh. Michael is the owner of Housh Home Energy in Ohio. He regularly works on natural gas equipment and is an active contributor to the HVAC School Facebook group. Thanks, Michael! Gas-fired equipment has a different set of components than your typical straight-cool […]