As HVAC/R Technicians, we use tools and instruments to take measurements every day. In fact, 90% of our job could not be done efficiently without some kind of measurement.  “How do we measure?” “With what instruments?” “How accurate are these measurements?” These are all questions a thoughtful technician should ask before spending money on a […]

The amount of pressure you're under depends on where you live. I live in Florida, so I'm very close to sea level. Therefore, the weight of the atmosphere is exerting exactly 14.7 pounds per square inch (PSIA) of pressure on every surface in every direction. There is no such thing as negative pressure—only pressure lower […]

  To start, I'm going to cut straight to the part that most of you want to know. This information is based on calculations I have done personally based on typical Mastercool DOT tanks, but feel free to come to your own conclusions based on your own calculations. I prefer to stay on the safe […]