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 […]

Here's the first question: Does it really matter if the speed taps on a motor are run or common? Well, yes… sort of. In some cases, it helps to identify if you're dealing with an open winding or an open thermal overload. The thermal overload breaks common, but you will still read a path between […]

The term “short” has become a meaningless phrase in common culture to mean “anything wrong with an electrical device.” A short circuit is a particular fault that can mean one of two things in technical lingo: 1. Any two circuits that are connecting in an undesigned manner This issue would be the case if a […]