Abstract: An improved evaporator unit in which a cooling tube core is placed between guide panels which permit a portion of the refrigerated air band to by-pass the front air opening of the core and to thereafter be forced into the core along a substantial longitudinal length of one or more side air openings. The flow of an auxilliary portion of the air stream into the side air opening permits the diffusion of frost build-up within the cooling tube core. A heater is provided for use during a defrost cycle in order to add heat directly into the cooling tube core. The improved evaporator is designed for use with reverse flow air defrost refrigerated container apparatus. Use of the evaporator permits improved refrigeration and defrost cycle operation.

Abstract: A closed circuit refrigeration system includes a compressor, a remote condenser coupled to the output of the compressor, a receiver tank coupled downstream of the condenser means, and one or more evaporators coupled between the receiver and compressor return. A bypass conduit is coupled between the condenser output and receiver input at one end and between the receiver output and evaporator input at the other end; and a temperature controlled valve selectively controls the flow of refrigerant through the bypass conduit as a function of the temperature of refrigerant at the condenser output. A check valve in the condenser output conduit prevents backflow of refrigerant during periods of low condenser pressure. A method of operating a closed circuit refrigeration system is included in which a receiver tank bypass line is controlled responsive to the condition of the refrigerant in the condenser output.

Abstract: An improved change of phase refrigeration system utilizing low compressor head pressures to maximize compressor efficiency, employing a relatively low temperature cooling medium to cool refrigerant gases, using a metering device which is operable at a relatively low pressure differential to feed condensate to the evaporator coil and providing additional controls to temporarily increase head pressure and thus condensate temperature when such increased temperature is needed for heat recovery or gas defrost. Because the proposed refrigeration system employs condensate at a relatively low temperature it may be necessary to enlarge the supply line for liquid refrigerant running from the condenser to the metering device to minimize evaporation of the condensate in the supply line. Further, it may be preferable to insulate the liquid refrigerant line so as to minimize premature evaporation of condensate in that line.