Abstract: A refrigerant-compression temperature regulation system providing for suction gas cooling includes: (a) a compressor for compressing the refrigerant in vapor and gaseous phase; (b) a condenser downstream from the compressor for condensing the compressed refrigerant to liquid phase; (c) a first valve downstream from the condenser for creating a predetermined pressure drop; (d) a first evaporator downstream from the first valve for transferring heat between a load and the refrigerant; (e) a suction gas return line leading from the first evaporator to the compressor for returning heated refrigerant to a suction inlet of the compressor; and, (f) a first indirect heat exchanger having a suction gas cooling path from the first valve to upstream of the first evaporator, the first indirect heat exchanger for passively transferring heat from the gas and vapor phase refrigerant in the suction gas return line to the vapor phase refrigerant entering the first evaporator.

Abstract: A vapor-compression refrigeration system has a continuously operating compressor, with loading on the compressor varied in accordance with conditions and cooling needs. The system avoids any on/off cycling of the compressor or valves in the system, but instead keeps cooling and bypass valves open to varying and proportional degrees depending upon requirements. The system includes several bypass loops, for bypassing coolant fluid to a proportional degree when a desired temperature is approached in a body to be cooled; and when temperature of return gas to the compressor approaches a limit temperature beyond which the compressor should not operate. In the latter case, cool liquid is injected, while expanding and vaporizing, into the hot gas for cooling, to protect the compressor.

Abstract: A method and apparatus for preventing compressor slugging in a vapor-compression system having an outlet and an inlet connected by a closed loop injects an immiscible charging gas such as nitrogen into the system in an amount sufficient to raise the system pressure by a predetermined amount. The charging gas is separated from the refrigerant and collected in a charging gas separation area of a receiver in the loop. The charging gas remains in the charging gas separation area of the receiver until the power to the compressor system is shut off. A valve in a branch line leading from the charging gas separation area of the receiver automatically opens when the power is lost which releases the charging gas to pressurize the compressor. Pressurization prevents refrigerant in the system from migrating into the compressor to cause slugging when the compressor is reactivated.

Abstract: A vapor-compression refrigeration system has a continuously operating compressor, with loading on the compressor varied in accordance with conditions and cooling needs. The system avoids any on/off cycling of the compressor or valves in the system, but instead keeps cooling and bypass valves open to varying and proportional degrees depending upon requirements. The system includes several bypass loops, for bypassing coolant fluid to a proportional degree when a desired temperature is approached in a body to be cooled; and when temperature of return gas to the compressor approaches a limit temperature beyond which the compressor should not operate. In the latter case, cool liquid is injected, while expanding and vaporizing, into the hot gas for cooling, to protect the compressor.

Abstract: A wide range temperature control system for controlling and maintaining the temperature of a first cooling liquid in an indirect heat exchanger at a predetermined setpoint within a wide range of temperatures is disclosed. The system proportions flow of a second cooling liquid between a cooling coil located in the heat exchanger and a bypass path. Flow through the bypass path is regulated by a temperature sensitive valve responsive to outflow temperature of the second cooling liquid from the heat exchanger. Bypassed flow mixes with the outflow from the heat exchanger and thereby establishes and maintains the temperature sensitive valve in a proportional flow mode. The flow of second cooling liquid through the cooling coil is proportioned to the differential in temperature between the second cooling liquid and the first cooling liquid and to the dynamic heat conditions within the heat exchanger at any time.