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 cooling system partially floods the low temperature low side heat exchangers (e.g., freezers) in the system. An accumulator is positioned between the low temperature low side heat exchangers and the low temperature compressor. The accumulator collects the refrigerant (both liquid and vapor) from the flooded low temperature low side heat exchangers. Refrigerant discharged by the low temperature compressor is fed through the accumulator so that heat can be transferred to the refrigerant collected in the accumulator. As a result, the temperature of the refrigerant discharged by the low temperature compressor drops before that refrigerant reaches the medium temperature compressor.

A heating, ventilation, and air-conditioning (HVAC) system for use with a refrigerant. The HVAC system may comprise a compressor, a condenser, an expansion device, an evaporator, and a separator. The compressor may be operable to compress the refrigerant. The condenser may be positioned downstream of the compressor and operable to condense the refrigerant. The expansion device may be positioned downstream of the condenser and operable to reduce a pressure of the refrigerant flowing therethrough. The evaporator may be positioned downstream of the expansion device and operable to vaporize the refrigerant from the expansion device. The separator may be positioned downstream of the expansion device and operable to separate the refrigerant into liquid refrigerant and gaseous refrigerant. The gaseous refrigerant from the separator and the liquid refrigerant from the separator may be combined prior to being compressed by the compressor.

A cooling system is designed to operate in two different modes. Generally, in the first mode, when parallel compression is needed, certain valves are controlled to direct gaseous refrigerant from a tank to a compressor in the system and to direct refrigerant from low side heat exchangers towards other compressors. In this manner, a compressor in the system is transitioned to be generally a parallel compressor. In the second mode, when parallel compression is not needed, the valves are controlled to return the refrigerant flow back to normal.

A refrigeration system is provided. The refrigeration system includes: an indoor heat exchange module configured for refrigerant to absorb heat; outdoor heat exchange modules for the refrigerant to dissipate heat. The outdoor heat exchange module includes a compression device and a condensing device; the outdoor heat exchange module is switchable between an active mode and a standby mode; in the active mode, the outdoor heat exchange module is connected to the indoor heat exchange module; in the standby mode, the outdoor heat exchange module is disconnected from the indoor heat exchange module, and the compression device of the outdoor heat exchange module is in an operation status.

An air-conditioning device includes a heater unit that heats the air to be lead to a vehicle cabin using the heat of the refrigerant compressed by a compressor, a liquid receiver arranged at the downstream side of an outside heat exchanger, a liquid receiver separating the refrigerant lead from the outside heat exchanger into a liquid-phase refrigerant and a gaseous-phase refrigerant and storing the liquid-phase refrigerant, and a restrictor mechanism provided between the heater unit and the outside heat exchanger, the restrictor mechanism decompressing and expanding the refrigerant. When there is a dehumidification request, the operation mode is temporarily switched from a dehumidifying cabin-heating mode which evaporates the refrigerant by an evaporating unit and radiates heat by the heater unit in the state in which the restrictor mechanism restricts the flow of the refrigerant, to the cabin-cooling mode which evaporates the refrigerant by the evaporating unit while promoting the storage of the liquid-phase refrigerant in the liquid receiver.

An air conditioner includes an inside condenser, an outside heat exchanger, an inside evaporator, a refrigerant circuit switcher, and an air passage switcher. The refrigerant circuit switcher is configured to switch a layout of the refrigerant circuit to (i) a first circuit during a heating mode such that the refrigerant releases heat at the inside condenser and is decompressed to evaporate at the outside heat exchanger and (ii) a second circuit during a defrosting mode such that the refrigerant releases heat at the outside heat exchanger and is decompressed to evaporate at the inside evaporator. The air passage switcher is configured to switch the air passage to (i) a first passage during the heating mode such that the air passes through the inside evaporator and the inside condenser and (ii) a second passage during the defrosting mode such that the air bypasses the inside condenser.

A thermal management system for a vehicle includes a heating refrigerant circulation circuit, a heat pump cycle and a heat-discharge refrigerant circulation circuit A heating circulation section of the heating refrigerant circulation circuit, a recovery circulation section of the heat pump cycle, and a heat-discharge circulation section of the heat-discharge refrigerant circulation circuit are integrally configured as a combined heat exchanger that is capable of performing heat transfers at least between the cycle refrigerant and the heating refrigerant and between the heat-discharge refrigerant and the heating refrigerant. Furthermore, the heating refrigerant, the cycle refrigerant and the heat-discharge refrigerant are heat mediums each of which has a phase change during the heat transfer.

A heat pump system includes a heat pump cycle, a heat medium circulation circuit, and a refrigeration cycle device. The refrigeration cycle device is configured to perform a defrosting operation when a frost formation determiner determines that frost is formed. A throttle opening degree controller is configured to increase an opening degree in the defrosting operation. A pumping capacity controller is configured to increase a pumping capacity in the defrosting operation with increase of a required heating capacity required for heating a heating target fluid, the pumping capacity controller increasing the pumping capacity such that heat of refrigerant discharged from a compressor is transferred to heat medium in a first heat exchanger within a range in which a temperature of the refrigerant flowing into an outside heat exchanger is capable of melting the frost formed on the outside heat exchanger.

A refrigeration cycle apparatus includes a refrigerant circuit which allows refrigerant to circulate therethrough, and an outdoor heat exchanger which exchanges heat between the refrigerant and outdoor air. The outdoor heat exchanger has first to third heat exchange sections. The second heat exchange section is located below the first heat exchange section, and the third heat exchange section is located below the second heat exchange section. In a refrigerant passage connecting the second and third heat exchange sections, a first pressure reducing device reduces a pressure of the refrigerant flowing through the refrigerant passage. In an operation mode in which the first and second heat exchange sections each serve as an evaporator, the third heat exchange section is located upstream of the second heat exchange section in the flow of the refrigerant, and refrigerant having a temperature higher than that of the outdoor air flows through the third heat exchange section.