Although purgers are commonly used on the high side of refrigeration systems to eliminate non-condensible gases, they leave behind all of the moisture and condensible impurities. The Phillips Anhydrator is designed to eliminate these efficiency-robbing substances in the low side of your system. The Anhydrator operates like a still by employing warm liquid from the high side to purify the ammonia, but also contains a unique self-balancing level control that ensures that the moisture and impurities left behind are not re-evaporated into the system. The entire system operates in a continuous process. You can tell when it's time to drain the impurities by observing the frost level on the vessel bottom or on the level pipe - when the frost is gone it's time to drain!
Look to the left for links to the Engineering Bulletin and Service Bulletin.