This article was written by Don Gillis with Chemours. Thanks, Don! There are 3 main reasons we use “P” or “U” traps: Assisting in oil return to the compressor Preventing oil accumulation in the evaporator  Preventing liquid refrigerant or oil from entering the compressor while operating or during the off cycle Assisting in oil return […]

I don't do much in the way of “rack” refrigeration. However, I recently had a conversation with experienced rack refrigeration tech Jeremy Smith, and he got me thinking about EPR valves. I've heard EPR (evaporator pressure regulator) valves called suction regulators or hold back valves. In essence, they hold back against the suction line to […]

  The second law of thermodynamics puts the first law into context and establishes entropy as a concept. We can simply define entropy as a state of disorder that can only increase or remain the same in natural processes. Processes in which entropy remains the same are reversible, but ones that result in an entropy […]