Abstract: The compressor of a transport refrigeration system is divided into two sections, with each section having a suction inlet. The refrigerant vapor from the evaporator is passed to one of the suction inlets, whereas the refrigerant vapor from a subcooler circuit is passed to the other suction inlet. A valve is operated to selectively insert or remove the subcooler as capacity requirements vary. In one embodiment, a six cylinder reciprocating compressor is used with five cylinders compressing within a first section, and a single cylinder compressing in the other section containing the subcooler circuit.

Abstract: A thermal storage monitoring and control system employed on a container refrigeration unit utilizes a "thermal flywheel" algorithm in combination with a data processor to control the temperature level within a cargo container to a maximum value. The thermal monitoring and control system operates the refrigeration system in a manner that causes the heat gain by the load during hot afternoons and evenings to be offset by the thermal storage built into the cargo. The monitoring and control system can be configured to operate automatically or manually.