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. Although we primarily work with our hands, our eyes are one of our most valuable assets in the industry. After all, […]

Oxidation is the loss of electrons, reduction is the gain of electrons, and the reaction is what occurs between the two. When we talk about chemistry or chemical reactions, we are really talking about an electrical interaction between molecules seeking equilibrium. In other the words, the old “high voltage goes to low voltage” rule applies […]

Sometimes, we can focus on the more complicated aspects of a system and parts installation—like evacuation and flowing nitrogen—and forget the simple and critical common-sense steps to keep contaminants out of the system. One of these is pre-cleaning the tubing and connection before cutting or unsweating. For example: If you are replacing a coil, use […]