This is the first of a three-part series of articles that will dive deep into advanced psychrometrics. The source material for each of these articles may be found in ACCA Manual P Sections 3, 4, and 5. This article is based on information found in Section 3.  Psychrometrics is the study of the physical and […]

This photo is of a blower door test we performed at my own house using a Retrotec blower door. You will notice the 15-passenger van outside the window, which is a dead giveaway. A blower door is used to measure the tightness of a building and is often discussed in terms of an ACH50 number. […]

First, let's cover the basics. X13 is a brand name for the Regal Beloit/Genteq brand of constant torque motors; there are other manufacturers that make them, but the term “X13” has become pretty much synonymous with the fractional horsepower HVAC constant torque motor. Also, this article is specifically discussing the common residential/light commercial motors. There are […]