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 […]

Many of us are aware that X13 and Fully variable motor failure has peaked over the last few years, and I'm sure there are multiple reasons for that. One of the reasons is fairly simple and can be traced back to two simple installation and service practices that can be easily implemented. Seal all air […]

This article is written by longtime tech Shaun McCann sharing his experiences with a big problem in our trade. Thanks for this, Shaun.  I started in the HVAC business working for a small commercial union shop in the late '80s. I left that job within a year and worked in the bar and restaurant business […]