The topic of static pressure comes up frequently in HVAC, and it’s sometimes presented as a test that can be all-knowing and insightful about what is happening with regard to airflow in a system. To use static pressure responsibly, we need to understand what it really is and what it means for an HVAC system. […]

Every HVAC/R tech needs an electronic leak detector nowadays, and with low-GWP HFC and HFO refrigerants getting more and more commonplace, every HVAC/R tech needs a VERY sensitive electronic leak detector. (Yes, electronic leak detection does work.) We often see three types, but let's toss out the corona discharge leak detector right off the top. […]

A while back, I had a tech who was having some trouble finding a 35 PSI (2.41 bar) make-on-fall pressure switch. One adjustable switch in the catalog said (SPDT), but he didn't quite understand what that meant. In that case, it means single-pole, double-throw, and the “double-throw” part means that the switch has terminals in both the […]