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.   Let’s be honest: most of us probably got into the HVAC trade because we enjoy working with our hands. Unfortunately, […]

To answer the question in the title, we use it as a measurement of pressure. REALLY, it is a measurement of distance. First, any scale CAN be used to measure vacuum (negative pressure) and positive pressure. The trick is knowing which is best suited for which and the size of the scale. Larger units of […]

There are many examples of teaching using metaphors to help someone grasp how something works without being EXACTLY correct. Some examples are how we often use water flow to explain electrical flow or refrigerant circuit dynamics. It's enough like the way it works to get our heads wrapped around it, but there are many differences. […]