At www.achrnews.com, The NEWS’ Extra Edition page is home to hundreds of online-exclusive service and maintenance, technical, and business management articles. Here are some of the best.
Evacuating a refrigeration system serves two primary objectives: It removes noncondensables, and it dehydrates (removes water vapor). If noncondensables such as air are not removed, the system will operate at higher than condensing pressures. This happens because the air is trapped at the top of the condenser, effectively reducing the condenser capacity. Increasing the condensing pressure results in higher compression ratios and higher discharge temperatures, both of which decrease system efficiency and can lead to decreased reliability.