Often in commercial HVAC and refrigeration, you'll come across a sight glass/moisture indicator on the liquid line. (Oil sight glasses also exist, but those are different from what I'm talking about today.) Sight Glass The sight glass portion is simple; it's just there to show if the liquid line has a full line of liquid […]

DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. Locking out and tagging equipment is one of the most basic safety procedures in general industry and maintenance work, especially in […]

Deburring copper tubing (often called reaming) is the practice of running a blade around the inside of tubing after you cut it to remove the burr edge from the inside. It's an important practice and should be performed whenever possible. Deburring reduces turbulence inside the lines, as burrs can cause turbulence.   HOWEVER… YOU MUST […]

Eric Mele, Eric Kaiser, and John Oaks come on the podcast to talk about commercial PM best practices and what matters most. Drain cleaning is a critical part of the standard commercial PM. You must assess the drainage situation (pitch, length, location, etc.) to plan your cleaning strategy and arrive at the best result: the […]

In today's podcast, I talk to John Oaks about his experience as a VRF tech in the field, including branch boxes and two-pipe vs. three-pipe technology. John primarily works on the troubleshooting and service side rather than the installation and programming side of the field. Variable refrigerant flow (VRF) systems, also called VRV systems when […]