Disclosed are climate systems and methods for control the climate systems. A climate system includes a refrigerant circuit, a first compressor, a second compressor, a first refrigerant-to-air heat exchanger, a second refrigerant-to-air heat exchanger, and a controller communicatively coupled to the first and second compressors. Respective outlets of the first and second compressors are fluidically coupled to the first refrigerant-to-air heat exchanger, the first refrigerant-to-air heat exchanger is fluidically coupled to the second refrigerant-to-air heat exchanger, and the second refrigerant-to-air heat exchanger is fluidically coupled with respective inlets of the first and second compressors. The fluidic connection between the second refrigerant-to-air heat exchanger and the first and second compressors includes a vertical split that is configured to mitigate or reduce the amount of compressor oil that migrates to dormant components.

Disclosed are climate systems and methods for control the climate systems. A climate system includes a refrigerant circuit, a first compressor, a second compressor, a first refrigerant-to-air heat exchanger, a second refrigerant-to-air heat exchanger, and a controller communicatively coupled to the first and second compressors. Respective outlets of the first and second compressors are fluidically coupled to the first refrigerant-to-air heat exchanger, the first refrigerant-to-air heat exchanger is fluidically coupled to the second refrigerant-to-air heat exchanger, and the second refrigerant-to-air heat exchanger is fluidically coupled with respective inlets of the first and second compressors. The fluidic connection between the second refrigerant-to-air heat exchanger and the first and second compressors includes a vertical split that is configured to mitigate or reduce the amount of compressor oil that migrates to dormant components.

A transportation refrigeration unit (TRU) and power system. The TRU and power system including a compressor configured to compress a refrigerant, an evaporator heat exchanger operatively coupled to the compressor, and an evaporator fan configured to provide return airflow and flow the return airflow over the evaporator heat exchanger. The system also includes a return air temperature (RAT) sensor disposed in the return airflow and configured measure the temperature of the return airflow, a TRU controller operably connected to the RAT sensor and configured to execute a process to determine an AC power requirement for the TRU based on at least the RAT; a generator power converter configured to receive a generator three phase AC power and provide DC power to an energy storage system, a power management system, the power management system configured to direct power the TRU based on the AC power requirement.

A vehicle air conditioning apparatus includes: a refrigerant circuit including: a compressor; an outdoor heat exchanger; a heat releasing device; a first electronic expansion valve; a refrigerant-heat medium heat exchanger; and a second electronic expansion valve; a heat medium circuit; and a controller. The controller has heating modes including: an outdoor air heat absorption heating mode to absorb heat from the outdoor heat exchanger; and a waste heat recovery heating mode to absorb heat from the refrigerant-heat medium heat exchanger. When the outdoor air heat absorption heating mode is switched to the waste heat recovery heating mode, the controller controls the first electronic expansion valve to be closed, and controls a degree of superheat of the refrigerant to be increased on a downstream side of the refrigerant-heat medium heat exchanger.

A method of operating a cooling system of a vehicle includes measuring a refrigerant pressure and a refrigerant temperature of a flow of refrigerant in a refrigerant circuit of the cooling system, estimating a relative humidity of a supply airflow across an evaporator of the refrigerant circuit utilizing the measured refrigerant pressure and the measured refrigerant temperature, and changing operation of one or more components of the refrigerant circuit as a result of the estimated relative humidity.

Methods for controlling an air conditioning system of a vehicle including a blower unit, a duct, an evaporator, a first heater and a first discharge temperature sensor, the evaporator and the first heater being located in the duct, the blower unit being configured to generate an airflow along the duct at a variable blower speed, the first discharge temperature sensor being configured to output a first discharge temperature sensed from the airflow in the duct located after the evaporator and first heater, the methods comprise: calculating a mass flow rate based on the blower speed of the blower unit; calculating a first heating level of the air conditioning system based on at least one first heater parameter associated with the first heater; and calculating an estimated evaporator operating temperature of the evaporator based on the first discharge temperature, the first heating level, and the mass flow rate.

A cooling system includes a compressor that compresses a refrigerant, a heat exchanger that cools the refrigerant from the compressor, heat exchangers that use the refrigerant cooled by the heat exchanger, a refrigerant passage that supplies the refrigerant from the heat exchangers to a battery, a refrigerant passage that supplies the refrigerant cooled by the heat exchanger to the refrigerant passage without passing the refrigerant through the heat exchangers an expansion valve provided on the refrigerant passage, and a flow control valve provided on the refrigerant passage, and a processing circuitry increases the opening degree of the flow control valve when the specific enthalpy of the refrigerant supplied to the battery exceeds a predetermine range and reduces the opening degree of the flow control valve when the specific enthalpy is below the predetermined range.