This tip was a COMMENT on the sensible heat ratio tip left by Jim Bergmann. As usual, Jim makes a great point; once you get the “sensible” capacity for a piece of equipment at a set of conditions, you can easily calculate a true target delta T. Another interesting thing you can do is use […]

Evaporator temperatures below 32° are common and acceptable in refrigeration; that's why there is a defrost sequence. In a heat pump running in heat mode, it's the same; freezing is a part of the process, and defrost is necessary. In comfort cooling, we can't allow the evaporator to get below 32°, or it will freeze. […]

The gas laws. We all learned about them in school and promptly forgot all about them. I really think that we need to dig our books out, dust that information off, and work to understand and apply it. Many will say that nitrogen pressure doesn't change with pressure like other gasses. That is false, but […]