Testo 557 vacuum gauge and Appion core removal tools shown I've had a change of heart. Back in the early 2000s, during the big construction boom, I did many system startups on residential units for a large company I worked for. When installers ran the line sets prior to startup, they weren't always very careful […]

I recently received a message asking for a discussion of relative humidity (RH), wet-bulb (WB), and dry-bulb (DB). Time and time again, I hear techs say that condensation occurs when “hot meets cold,” which may be true in some cases. However, that is only a shorthand way to describe it and doesn't really address what […]

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 […]