The grounding and bonding process is important, and it's a fairly broad topic. In HVAC/R, we generally just need to make sure that we properly connect the conductors (wires) provided to the proper connection points in the equipment and occasionally the disconnects. These connection lugs or green screws are rated for grounding so long as […]

Basic Compressor Functions The compressor's job is to circulate refrigerant through the system by means of vapor compression, similar to the way your heart moves blood through your circulatory system. Refrigerant circulation is measured in lbs/min or lbs/hour; this is called mass flow rate—the mass flow rate changes depending on the density of the refrigerant […]

Testo 760 Category IV Multimeter I was standing at a booth at the HVAC Excellence Educators conference, and an instructor walks up, grabs a meter, and asks me, “What's the difference between a category 3 and a category 4 meter?” Well, I really wasn't sure, but I knew that the category 4 meter is rated […]