What should the delta T (ΔT) be? What do you mean!? 20 degrees, of course! We are referring to the air temperature drop across an air handling unit or evaporator coil in cooling mode. Actually, depending on who you ask, the answer will range between 18-22 degrees Fahrenheit. Heck, I’ve heard some insist that […]

I got in one of these tiny torches the other day to experiment with brazing aluminum in tight spots, and one of the techs walked in and asked, “What type of torch is that?” I answered, “It's oxy/acetylene.” He picked it up and looked at it a bit, then asked, “Does that get hot enough […]

You may have heard about “swamp coolers” before. Surprisingly, we don’t see too many of them in Florida—even though the state is famous for its swamps.  Contrary to their name, swamp coolers are common in arid (dry) climates. They’re also called evaporative coolers because they use the evaporation process to cool the air.  This article […]