January is a good time for taking stock, looking back over what’s been achieved and looking forward to what is to come. 2020 has a particular significance because it is the year that the Montreal Protocol restriction on the use

When I was a small kid, whenever there was a discussion or disagreement about what was happening, my mother would say “Well, we will compromise and do it my way.” It was years before I learned that this is not

For many, many years I’ve found the word “zeotrope” disconcerting and upsetting. I didn’t know why; it just irked me. When I was in high school studying chemistry, we learned about azeotropes, unusual mixtures of liquids, which didn’t distill when

The idea of mixing two fluorocarbons to provide a refrigerant that behaved like a single fluid but with beneficial properties was commercialized in the 1950s with the introduction of R-500, R-501 and R-502. ASHRAE Standard 34, which was originally published

The two most recent columns in this series may have seemed unnecessarily gloomy about zeotropic refrigerant blends. However, like most things in life that have unusual features, there are ways in which their oddities can be used to advantage. A

I’m writing this from my “home office,” also known as the attic, in the midst of the pandemic lockdown that has affected so much of the world in the last few months. I hope that by the time you are

When the Fourth of July celebrations are fading into the morning after the night before, please take a moment to raise a glass to Professor William Rankine on the occasion of his 200th birthday. I had hoped to be leading

The saying “nature abhors a vacuum” is attributed to Aristotle who mused on the nature of voids in Book IV of his lectures on physics. Unlike Aristotle and Mother Nature, refrigeration technicians ought to have a healthy love of vacua

In last month’s column I wrote about the process of pulling a vacuum on refrigerating systems and highlighted some good practice points for care of the vacuum pump and how it is connected to the system for best effect. Here

This is the third of three columns focused on the process of evacuating a refrigeration system and focuses on the test element of that process, including a look at how the vacuum fits within the rest of the test regime.