Abstract: Method of stacking refrigerated shipping containers (10) including categorizing a plurality of refrigerated shipping containers (10) as a low temperature container (L) or a high temperature container (H), each of the refrigerated shipping containers (10) having a condenser (16). The method also includes disposing the plurality of refrigerated shipping containers (10) relative to each other based on the temperature categorization of the refrigerated shipping containers (10).

Abstract: A method of determining charge loss of a refrigeration system includes the steps of inputting an ambient temperature, a box temperature, and a compressor speed into an electronic controller of the refrigeration system, and calculating a first air side temperature difference across an evaporator by applying an algorithm having a first T-Map representative of normal operating conditions. The controller may then confirm a detection prerequisite is satisfied. Upon confirmation, the controller calculates a second air side temperature difference across the evaporator by applying the algorithm having a second T-Map representative of a loss of refrigerant charge. An action may then be taken from the controller if the first air side temperature difference is less than the second air side temperature difference.

Abstract: Operation of a transcritical refrigerant vapor compression system is controlled, when operating in a high capacity mode, through control of the refrigerant pressure in the refrigerant heat rejection heat exchanger (40) or the compressor (30) discharge pressure, also referred to herein as the high side pressure, so as to optimize energy efficiency. When operating in unloaded low capacity mode, such as for chilling perishable product during temperature maintenance operation, the high side pressure is controlled so that the system can operate in a continuous running mode.

Abstract: Method of stacking refrigerated shipping containers (10) including categorizing a plurality of refrigerated shipping containers (10) as a low temperature container (L) or a high temperature container (H), each of the refrigerated shipping containers (10) having a condenser (16). The method also includes disposing the plurality of refrigerated shipping containers (10) relative to each other based on the temperature categorization of the refrigerated shipping containers (10).

Abstract: A method of determining charge loss of a refrigeration system includes the steps of inputting an ambient temperature, a box temperature, and a compressor speed into an electronic controller of the refrigeration system, and calculating a first air side temperature difference across an evaporator by applying an algorithm having a first T-Map representative of normal operating conditions. The controller may then confirm a detection prerequisite is satisfied. Upon confirmation, the controller calculates a second air side temperature difference across the evaporator by applying the algorithm having a second T-Map representative of a loss of refrigerant charge. An action may then be taken from the controller if the first air side temperature difference is less than the second air side temperature difference.

Abstract: A method is provided for protecting a refrigerant vapor compression system during a standstill period following shutdown of the refrigerant vapor compression system. A method is provided for detecting a low refrigerant charge level in a refrigerant vapor compression system operating in a transcritical mode. A refrigerant vapor compression system is provided that includes a controller operative to perform a refrigerant charge detection method.

Abstract: A method for operating a defrost mode of a transport refrigerant vapor compression system includes initiating a defrost operation for the transport refrigerant vapor compression system by energizing heaters operatively coupled to a heat absorption heat exchanger operable to defrost the heat absorption heat exchanger. During the defrost operation, the method includes comparing the heat absorption heat exchanger pressure to the first predetermined limit; in response to the heat absorption heat exchanger pressure being less than the first predetermined limit, performing at least one operation to determine if the defrost operation should be exited; and in response to the heat absorption heat exchanger pressure being greater than the first predetermined limit, exiting the defrost operation.

Abstract: A refrigerant vapor compression system includes a compression device having at least a first compression stage and a second compression stage arranged in series refrigerant flow relationship; a first refrigerant heat rejecting heat exchanger disposed downstream with respect to refrigerant flow of the second compression stage for passing the refrigerant in heat exchange relationship with a first secondary fluid; a second refrigerant heat rejecting heat exchanger disposed downstream with respect to refrigerant flow of the first refrigerant heat rejecting heat exchanger for passing the refrigerant in heat exchange relationship with a second secondary fluid.

Abstract: A transport refrigerant vapor compression system includes a controller for controlling operation of the transport refrigerant vapor compression system. The controller is configured to modulate a discharge pressure of the refrigerant compression device to control a cooling capacity of the transport refrigerant vapor compression system. The controller is configured to modulate the discharge pressure of a refrigerant compression device to control the cooling capacity of the transport refrigerant vapor compression system using both a refrigerant reservoir and an auxiliary expansion device without affecting superheat of the transport refrigerant vapor compression system.

Abstract: A method is disclosed or detecting a frozen evaporator coil of a refrigerant vapor compression system for supplying conditioned air to a temperature controlled space before ice build-up on the evaporator coil becomes so excessive as to result in an undesirable on-off cycling of the refrigerant vapor compression system compressor when operating to a frozen temperature maintenance mode. The method may also include initiating a defrost of a frozen evaporator coil of the refrigerant vapor compression system before ice build-up on the evaporator coil becomes so excessive as to result in an on-off cycling of the refrigerant vapor compression system compressor when operating to a frozen temperature maintenance mode.

Abstract: A refrigerant vapor compression system includes a compression device having at least a first compression stage and a second compression stage, a refrigerant heat rejection heat exchanger disposed downstream with respect to refrigerant flow of the second compression stage, and a refrigerant intercooler disposed intermediate the first compression stage and the second compression stage. The refrigerant intercooler is disposed downstream of the refrigerant heat rejection heat exchanger with respect to the flow of a secondary fluid. A second refrigerant heat rejection heat exchanger may be disposed downstream with respect to refrigerant flow of the aforesaid refrigerant heat rejection heat exchanger, and a second refrigerant intercooler may be disposed intermediate the first compression stage and the second compression stage and downstream with respect to refrigerant flow of the aforesaid refrigerant intercooler.

Abstract: A carbon dioxide refrigerant vapor compression system and method of operating that system are provided. The refrigerant vapor compression system includes a compression device, a flash tank receiver disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger, and a compressor unload circuit including a refrigerant line establishing refrigerant flow communication between an intermediate pressure stage of the compression device and the refrigerant circuit at a location downstream of the refrigerant heat absorption heat exchanger and upstream of a suction inlet to the compression device, and a unload circuit flow control device disposed in said unload circuit refrigerant line. In response to at least one system operating parameter sensed by at least one sensor, the controller selectively positions the unload flow control device to maintain the refrigerant vapor compression system operating below a preselected high pressure limit.

Abstract: A method for distributing a refrigerant charge level in a refrigerant vapor compression system includes restarting a stopped refrigerant compression device in a first mode; operating a primary expansion device independent of refrigerant heat absorption heat exchanger superheat; comparing a condition at a refrigerant reservoir to a prescribed condition; wherein when the condition is below the prescribed condition for a prescribed interval, operating the primary expansion device to control the refrigerant heat absorption heat exchanger superheat; and transitioning the refrigerant vapor compression system to a second mode.

Abstract: A method is provided for detecting in real-time a refrigerant charge loss in a refrigerant vapor compression system. If both a sensed evaporator outlet superheat exceeds a target evaporator outlet superheat by at least a preset amount of superheat and a sensed degree of openness of an electronic expansion valve exceeds a preset degree of openness for a preset time of period, and a sensed air temperature of either a flow of supply air having traversed the evaporator or a flow of return air returning to the evaporator is changing at a rate less than preset air temperature rate of change, a service alarm is generated indicating a loss of charge warning.

Abstract: A refrigeration system includes a compressor having a first stage and a second stage; a heat rejecting heat exchanger including an inter-cooler and a gas cooler, the intercooler coupled to an outlet of the first stage and the gas cooler coupled to an outlet of the second stage; an unload valve coupled to an outlet of the intercooler and a suction port of the first stage; a flash tank coupled to an outlet of the gas cooler; a primary expansion device coupled to an outlet of the flash tank; a heat absorbing heat exchanger coupled to an outlet of the primary expansion device, an outlet of the heat absorbing heat exchanger coupled to the suction port of the first stage; and a controller for executing a startup process including controlling the unload valve to direct refrigerant from the intercooler to the suction port of the first stage.

Abstract: A method for determining proper wiring of multiple three-phase motors in a refrigeration system is disclosed. The method may include energizing a plurality of three-phase motors with a first input phase rotation and recording performance data, energizing the plurality of three-phase motors with a second input phase rotation and recording the performance data, evaluating the performance data and determining if each of three-phase motors is properly wired, operating the refrigeration system in a normal mode if all of the three-phase motors are properly wired, or operating the refrigeration system in a less efficient mode if at least one three-phase motor is improperly wired.

Abstract: Operation of a transcritical refrigerant vapor compression system for supplying temperature conditioned air to a temperature controlled space is controlled when staging up or staging down to avoid undesirable overshoot and undershoot of the narrow temperature band bounding the control temperature set point for the temperature within the temperature controlled space.

Abstract: Operation of a transcritical refrigerant vapor compression system is controlled, when operating in a high capacity mode, through control of the refrigerant pressure in the refrigerant heat rejection heat exchanger (40) or the compressor (30) discharge pressure, also referred to herein as the high side pressure, so as to optimize energy efficiency. When operating in unloaded low capacity mode, such as for chilling perishable product during temperature maintenance operation, the high side pressure is controlled so that the system can operate in a continuous running mode.

Abstract: A method is disclosed or detecting a frozen evaporator coil of a refrigerant vapor compression system for supplying conditioned air to a temperature controlled space before ice build-up on the evaporator coil becomes so excessive as to result in an undesirable on-off cycling of the refrigerant vapor compression system compressor when operating to a frozen temperature maintenance mode. The method may also include initiating a defrost of a frozen evaporator coil of the refrigerant vapor compression system before ice build-up on the evaporator coil becomes so excessive as to result in an on-off cycling of the refrigerant vapor compression system compressor when operating to a frozen temperature maintenance mode.

Abstract: A method is provided for detecting in real-time a refrigerant charge loss in a refrigerant vapor compression system. If both a sensed evaporator outlet superheat exceeds a target evaporator outlet superheat by at least a preset amount of superheat and a sensed degree of openness of an electronic expansion valve exceeds a preset degree of openness for a preset time of period, and a sensed air temperature of either a flow of supply air having traversed the evaporator or a flow of return air returning to the evaporator is changing at a rate less than preset air temperature rate of change, a service alarm is generated indicating a loss of charge warning.