Stay Rates of Foreign Doctorate Recipients from U.S. Universities, 2013

A pressure accumulator receives liquid refrigerant from the receiver and supplies it to the evaporators. Liquid from the evaporators is temporarily stored in an upper accumulator from which it may drain to a drum which can be pressurized to return it to the pressure accumulator. A gaseous refrigerant connection from the receiver supplies pressure for the accumulator and for defrosting the evaporators, the arrangement eliminating the need for individual back pressure valves for each evaporator or group of evaporators during defrosting.