Excerpt from ACHR News article by Jack Sine -

"Everyone knows that excess oil in a chiller’s refrigerant can create serious performance problems. But what many don’t know is the frequency with which oil migrates to the refrigerant side and what percentage of chillers and refrigeration systems suffer from oil logging."

"In recent years, the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) has been emphasizing that not only does oil entrained in the refrigerant of a chiller significantly degrade performance, but it is also a far more common problem than previously thought."

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