A refrigerant leakage determination system capable of detecting leakage of refrigerant without requiring complicated processing is provided. A refrigerant leakage determination system is a refrigerant leakage determination system of a refrigeration cycle apparatus that includes a refrigerant circuit including a heat-source-side heat exchanger and has, as operating modes, a normal mode in which the heat-source-side heat exchanger is caused to function as an evaporator and a defrosting mode in which the heat-source-side heat exchanger frosted during a normal operation is defrosted. The refrigerant leakage determination system includes a processor configured to acquire defrosting information regarding a relationship between a normal operation period and the number of defrosting operations, and memory that stores the defrosting information. The processor is further configured to determine, based on the acquired defrosting information, leakage of refrigerant in the refrigerant circuit.

A method for operating a refrigeration system for a motor vehicle. The method includes setting an operating mode of the refrigeration system having active primary line and inactive secondary line or having active secondary line and inactive primary line; detecting the pressure in the inactive line; and activating and extraction of refrigerant from the inactive line into the active line by lowering the pressure in the active line to a value below the pressure in the inactive line and by opening the relevant valve device.

A cooling system comprising a cooling circuit connecting a heat exchanger and a heat load. The cooling system comprising a first velocity fuse upstream of the heat exchanger or heat load and a second velocity fuse or valve downstream of the heat exchanger or heat load. The heat exchanger or heat load is dynamically isolated from the rest of the cooling system by the first velocity fuse or the second velocity fuse in response to a velocity of a flow of cooling fluid exceeding a respective velocity setting of the first velocity fuse or the second velocity fuse.

A controller for a refrigeration system includes a processing circuit having one or more processors and memory. The processing circuit is configured to calculate a superheat of a gas refrigerant exiting a first side of a subcooler based on a measured temperature and a measured pressure of the gas refrigerant and compare the calculated superheat to a superheat threshold. In response to a determination that the calculated superheat is less than the superheat threshold, the processing circuit closes an expansion valve to restrict a flow of the gas refrigerant through a second side of the subcooler. In response to a determination that the calculated superheat is equal to or greater than the superheat threshold, the processing circuit operates the expansion valve to drive a temperature of a subcooled liquid refrigerant exiting the second side of the subcooler to a subcooled liquid temperature setpoint.

A thermal management device having an indirect air conditioning circuit for a motor vehicle is disclosed. The device has a first refrigerant fluid loop (A) with a compressor, a two-fluid heat exchanger, a first expansion device, an evaporator, a second expansion device, an evaporator/condenser, and a first by-pass line including a first stop valve, a first and a second internal heat exchanger. A second by-pass line includes a third expansion device arranged upstream from a cooler, a shunt branch comprising a first external radiator. The device also has a second heat transfer fluid loop (B) in which a heat transfer fluid is intended to flow. The two-fluid heat exchanger is arranged jointly on the one hand on the first refrigerant fluid loop downstream of the compressor, between said compressor and the first expansion device, and on the second heat transfer fluid loop (B).

A vehicle air conditioner having a compressor to compress a refrigerant, an air flow passage to supply air to the vehicle; a radiator; an outdoor heat exchanger; a battery temperature adjustment device for letting a heat medium circulate through a battery mounted in the vehicle, thereby adjusting a temperature of the battery; and a control device. The battery temperature adjustment device has a refrigerant-heat medium heat exchanger for performing exchange of heat between the refrigerant and the heat medium. The control device is configured to execute: a radiator and outdoor heat exchanger heating/battery cooling mode, and an obstruct inflow heating/battery cooling mode.

The present invention concerns a thermal management device comprising an indirect air-conditioning circuit (1) for a motor vehicle, comprising: a first refrigerant loop (A) comprising, in the direction of flow of the refrigerant, a compressor (3), a two-fluid heat exchanger (5), a first expansion device (7), a first heat exchanger (9) arranged inside a first heating, ventilation and air-conditioning device (X), a second expansion device (11), a second heat exchanger (13), and a first bypass duct (30) comprising a first stop valve (33), a first inner heat exchanger (19), a second inner heat exchanger (19′), a second bypass duct (40) comprising a third expansion device (17) arranged upstream from a first cooler (15), a third bypass duct (80) comprising a first additional heat exchanger (9′) arranged in a second heating, ventilation and air-conditioning device (Y), a second heat transfer fluid loop (B).

A valve assembly includes a valve body defining a cylindrical passage therein about an axis. An inlet port is defined in or near a first end of the valve body. First and second outlet ports are defined in the valve body extending radially outward from the cylindrical passage. A cylindrical valve spool having a central passage is positioned within, and sealingly engaged with, the cylindrical passage. The valve spool is moveable along the axis among: a first position wherein the inlet port is in fluid communication with the first outlet port but not the second outlet port, a second position wherein the inlet port is in fluid communication with the second outlet port but not the first outlet port, and an intermediate position between the first and second positions wherein the inlet port is in fluid communication with both of the first and second outlet ports.

In the present invention, a recuperator is used in a refrigerant cycle to make a heat exchange between a refrigerant generated in a condenser and a refrigerant before flowing into a compressor, thereby supercooling the refrigerant to minimize the quality of the refrigerant introduced into an evaporator, elevating temperatures at an inlet and an outlet of the compressor, and increasing condensed heat of the condenser. In the present invention, a recuperator is used to increase condensed heat of the condenser, leading to increasing the heat which circulation water circulating in a steam producing cycle receives from the condenser, whereby steam production efficiency can be improved.

A heating, ventilation, and/or air conditioning (HVAC) unit includes a first sensor disposed adjacent to an inlet of an evaporator configured to receive an airflow. The HVAC unit includes a second sensor disposed adjacent to an outlet of a reheat coil positioned downstream of the evaporator and configured to expel the airflow. The HVAC unit also includes a controller configured to regulate operation of a modulating reheat valve to adjust flow of a working fluid in thermal communication with the airflow to control a difference between a measurement of the first sensor and a measurement of the second sensor.