Abstract: A transport refrigeration system (TRS) and method of controlling temperature using an unloader manifold. The TRS includes a heat transfer circuit, the heat transfer circuit includes a compressor with a first cylinder bank and a second cylinder bank, and an unloader manifold with a first end connected to the first and second cylinder bank and a second end connected to a hot gas line in the heat transfer circuit. The first and second cylinder banks and the hot gas line are in fluid communication via the unloader manifold such that a heat transfer fluid can flow therethrough. The TRS further includes an unloader discharge controller to unload, via the unloader manifold, heat transfer fluid from the first cylinder bank to a first discharge level.

Abstract: A transport refrigeration system (TRS) includes a first heat transfer circuit including a first compressor, a condenser, a first expansion device, and a cascade heat exchanger. The first compressor, the condenser, the first expansion device, and the cascade heat exchanger are in fluid communication such that a first heat transfer fluid can flow therethrough. The TRS includes a second heat transfer circuit including a second compressor, the cascade heat exchanger, a second expansion device, and an evaporator. The second compressor, the cascade heat exchanger, the second expansion device, and the evaporator are in fluid communication such that a second heat transfer fluid can flow therethrough. The first heat transfer circuit and the second heat transfer circuit are arranged in thermal communication at the cascade heat exchanger such that the first heat transfer fluid and the second heat transfer fluid are in a heat exchange relationship at the cascade heat exchanger.

Abstract: A refrigeration system having a cooling circuit, a heating circuit, a pressurizing receiver tank circuit, a pilot circuit and a liquid injection circuit wherein the hot gas line includes a solenoid valve that connects an outlet of a compressor to an outlet of a receiver tank, and wherein the liquid injection circuit includes a liquid injection solenoid that connects the outlet of the receiver tank to an outlet of an economizer.

Abstract: A transport refrigeration unit (TRU) includes a compressor. The TRU further includes a condenser disposed downstream of the compressor. The TRU further includes an expansion device disposed downstream of the condenser. The TRU further includes a first flow control device disposed downstream of the condenser. The TRU further includes a first evaporator disposed downstream of the expansion device and the first flow control device. The first evaporator is disposed upstream of a second flow control device. The second evaporator is disposed downstream of the first How control device., the expansion device, and the second flow control device. The second evaporator includes a thermal accumulator. The second flow control device disposed upstream of the compressor.

Abstract: Systems and methods are described herein to use a discharge pressure of a compressor to drive refrigerant in a refrigeration system. Particularly, systems and methods are described herein to help recover liquid refrigerant from a liquid refrigerant section and/or a condenser coil to be used in a heating/defrost mode in a transport refrigerant unit (TRU). The liquid refrigerant can be recovered by directing the discharge refrigerant of the compressor to a liquid refrigerant section, which may include a receiver tank, a dryer and associated refrigerant lines, and/or a condenser coil. The discharge pressure of the discharge port can help drive refrigerant trapped in the liquid refrigerant section and/or the condenser coil into the heating/defrost branch of the TRU, which may include an evaporator coil, an accumulator tank and/or associated refrigerant lines.

Abstract: An auxiliary subcooling circuit for a transport refrigeration system (TRS) is provided. The auxiliary subcooling circuit may be configured to be driven by a compressor that is separate from a main compressor of a main refrigeration system of the TRS. The auxiliary subcooling circuit can be configured to subcool refrigerant in the main refrigeration system. The auxiliary subcooling circuit and the main refrigeration system may be configured to be driven by a prime mover of the TRS. An engaging device is configured to allow the auxiliary subcooling circuit to engage or disengage the prime mover. Methods to control the TRS are also provided.

Abstract: Methods and systems for controlling the operation of the evaporator fans in a transport refrigeration system (TRS) are described. In some examples, the TRS is a multi-zone temperature control system (MTCS). The methods and systems described herein generally dynamically control a plurality of system fans in MTCSs in instances where running the system fans can lead to inefficiencies in energy consumption and fluctuations in temperature control.

Abstract: A refrigeration system having a cooling circuit, a heating circuit, a pressurizing receiver tank circuit, a pilot circuit and a liquid injection circuit wherein the hot gas line includes a solenoid valve that connects an outlet of a compressor to an outlet of a receiver tank, and wherein the liquid injection circuit includes a liquid injection solenoid that connects the outlet of the receiver tank to an outlet of an economizer.

Abstract: A refrigeration system having a cooling circuit, a heating circuit, a pressurizing receiver tank circuit, a pilot circuit and a liquid injection circuit wherein the hot gas line includes a solenoid valve that connects an outlet of a compressor to an outlet of a receiver tank, and wherein the liquid injection circuit includes a liquid injection solenoid that connects the outlet of the receiver tank to an outlet of an economizer.

Abstract: A refrigeration system having a cooling circuit, a heating circuit, a pressurizing receiver tank circuit, a pilot circuit and a liquid injection circuit wherein the hot gas line includes a solenoid valve that connects an outlet of a compressor to an outlet of a receiver tank, and wherein the liquid injection circuit includes a liquid injection solenoid that connects the outlet of the receiver tank to an outlet of an economizer.

Abstract: A temperature control system for a container includes a refrigeration circuit having a primary fluid circulating therein and a secondary fluid circuit in communication with a first compartment of the container and a second compartment of the container. The secondary fluid circuit has a secondary fluid separate from the primary fluid circulating therein. The secondary fluid circuit includes a first heat exchange module in communication with an interior load space of the first compartment and a second heat exchange module in communication with an interior load space of the second compartment. Each of the first and second heat exchange modules includes a pump, a heater, a heat exchanger, and a three-way valve. A heat exchange interface between the refrigeration circuit and the secondary fluid circuit is operable to transfer heat from the secondary fluid to the primary fluid.

Abstract: A temperature control system includes a compressor, a condenser, an evaporator, and an accumulator. A liquid level sensor is associated with the accumulator tank generates a signal indicative of the level of the liquid heat transfer fluid inside the accumulator. A valve is in fluid communication with the condenser, the compressor, and the evaporator and is operable in a first position and a second position. The first position directs the heat transfer fluid from the compressor to the condenser, and the second position directs the heat transfer fluid from the compressor to the evaporator without passing through the first heat exchanger. A controller is in electrical communication with the liquid level sensor and the valve and is operable to receive the signal and move the valve from the first position to the second position based on the signal.

Abstract: A temperature control system for a container includes a refrigeration circuit having a primary fluid circulating therein and a secondary fluid circuit in communication with a first compartment of the container and a second compartment of the container. The secondary fluid circuit has a secondary fluid separate from the primary fluid circulating therein. The secondary fluid circuit includes a first heat exchange module in communication with an interior load space of the first compartment and a second heat exchange module in communication with an interior load space of the second compartment. Each of the first and second heat exchange modules includes a pump, a heater, a heat exchanger, and a three-way valve. A heat exchange interface between the refrigeration circuit and the secondary fluid circuit is operable to transfer heat from the secondary fluid to the primary fluid.

Abstract: A temperature control unit and a method of operating a temperature control unit. The temperature control unit including a refrigeration circuit enclosing a refrigerant and having a compressor, a condenser, and an evaporator coil. The method including providing a first flow path extending through the compressor, the condenser, and the evaporator, providing a second flow path extending through the compressor and the evaporator, the second flow path bypassing a section of the refrigeration circuit, directing refrigerant through the first flow path during operation in a cooling mode, directing refrigerant through the second flow path during operation in a heating mode, and recovering refrigerant from the section of the refrigeration circuit during operation in a recovery cycle.