Provided is an air conditioning apparatus. The air conditioning apparatus includes a heat exchanger in which the refrigerant and the water are heat-exchanged with each other, a high-pressure guide tube extending from a high-pressure gas tube of an outdoor unit so as to be connected to one side of the heat exchanger, a low-pressure guide tube extending from a low-pressure gas tube of the outdoor unit so as to be combined with the high-pressure guide tube, a liquid guide tube extending from a liquid tube of the outdoor unit so as to be connected to the other side of the heat exchanger, a bypass tube configured to connect a bypass branch point of the high-pressure gas tube to a bypass combination point of the liquid guide tube to bypass a high-pressure refrigerant existing in the high-pressure tube to the liquid guide tube, and a bypass valve installed in the bypass tube.

An air conditioner includes a bypass pipe connecting a first bypass branch of a first connection pipe, through which high-pressure refrigerant flows, with a second bypass branch of a third connection pipe, through which low-pressure refrigerant flows, to allow bypassing of high-pressure refrigerant in the first connection pipe to the third connection pipe, and a bypass valve mounted in the bypass pipe. During a cooling operation of an indoor unit, the bypass valve is opened to allow bypassing of high-pressure refrigerant of the first connection pipe to the third connection pipe.

An air conditioning apparatus is provided that may include an outdoor unit including a compressor and an outdoor heat exchanger and through which a refrigerant is circulated, an indoor unit through which a fluid, such as water is circulated, and at least one heat exchange device including a heat exchanger in which the refrigerant and the fluid are heat-exchanged with each other. The at least one heat exchange device may include a high-pressure guide tube that extends from a high-pressure gas tube of the outdoor unit so as to be connected to a first side of the heat exchanger, a low-pressure guide tube that extends from a low-pressure gas tube of the outdoor unit so as to be combined with the high-pressure guide tube, a liquid guide tube that extends from a liquid tube of the outdoor unit so as to be connected to a second side of the heat exchanger, and a solenoid valve installed in the high-pressure guide tube or the low-pressure guide tube to perform an opening and closing operation so as to allow the refrigerant to flow in a first direction. The high-pressure gas tube and the low-pressure gas tube may be connected to each other by a single gas tube, and when the indoor unit performs a cooling operation or a heating operation, flow of refrigerant in the first direction may be blocked in a state in which power is applied to the solenoid valve.

Noise that is generated from an indoor unit is suppressed when performing two-phase transport of refrigerant by using a liquid-pressure-adjusting expansion valve in an air conditioner including an outdoor unit, a plurality of indoor units each including an indoor heat exchanger, a relay unit that switches the plurality of indoor heat exchangers so that the indoor heat exchangers individually function as an evaporator or radiator for refrigerant, and a liquid-refrigerant connection pipe and a gas-refrigerant connection pipe that connect the outdoor unit and the indoor unit via the relay unit. The relay unit includes a relay expansion valve that further decompresses the refrigerant that has been decompressed by the liquid-pressure-adjusting expansion valve.

The present invention relates to a cooling system for a low temperature storage. The cooling system for the low temperature storage according to an embodiment of the present invention comprises: a first outdoor valve disposed between a compressor and an outdoor heat exchanger and selectively restricting an inflow of a refrigerant into the outdoor heat exchanger; and a first bypass pipe branched from an inlet side of the first outdoor valve and guiding the refrigerant to bypass the outdoor heat exchanger, so that the refrigerant can be guided to bypass the outdoor heat exchanger during defrosting operation of the cooling system.

A heating, ventilation, and air conditioning system in which a primary water loop is used as a heat transfer reservoir for both heating and cooling. A plurality of micro chillers are provided, with each micro chiller being connected to the primary water loop. Each micro chiller includes its own heat engine. Each micro chiller includes one or more fan control units that exchange heat between the micro chiller and the air in a building. In a first mode a micro chiller transfers heat from the air in the building to the water circulating within the primary water loop. In a second mode the micro chiller transfers heat from the water circulating in the primary water loop to the air in the building. A primary water loop regulation system is provided to control the temperature of the water circulating in the primary water loop.

An air-conditioning apparatus includes a refrigerant circuit in which an outdoor unit, at least one load-side expansion device, and at least one load-side heat exchanger are connected by pipes to allow refrigerant to circulate. The outdoor unit includes a compressor including an injection port allowing the refrigerant to flow into a suction chamber, a heat-source-side heat exchanger for heat exchange for the refrigerant, and an accumulator. The load-side heat exchanger transfers heat between a load and the refrigerant. The outdoor unit includes: an injection pipe having one end connected between the heat-source-side heat exchanger and the load-side expansion device, and the other end connected to the injection port, in the refrigerant circuit; an outdoor-side expansion device located downstream from the one end of the injection pipe in the flow of the refrigerant from the load-side expansion device to the heat-source-side heat exchanger; and an injection expansion device that adjusts the amount of the refrigerant flowing through the injection pipe. Also, a controller is provided to control the opening degrees of the outdoor-side expansion device and the injection expansion device.

An air conditioning system, including a compressor, two outdoor heat exchange units, a liquid pipe used for communicating with indoor units, a high-pressure gas tube and a low-pressure gas tube; the air conditioning system further includes a valve assembly. One outdoor heat exchange unit has a first state in which one end thereof communicates with the high-pressure gas tube and another end thereof communicates with the liquid pipe, and has a second state in which one end thereof communicates with the low-pressure gas tube and the other end thereof communicates with the liquid pipe. Further disclosed is a control method for the air conditioning system.

A refrigeration cycle apparatus includes: an outdoor unit; a branch unit connected to the outdoor unit via a first pipe and a second pipe; a first indoor unit connected to the branch unit via a third pipe and a fourth pipe; and a second indoor unit connected to the branch unit via a fifth pipe and a sixth pipe. A refrigerant circuit includes a compressor, a first heat exchanger, a second heat exchanger, a third heat exchanger, and a six-way valve. The six-way valve switches between a first state in which the first heat exchanger acts as a condenser and at least the second heat exchanger acts as an evaporator and a second state in which the first heat exchanger acts as an evaporator and at least the second heat exchanger acts as a condenser.

An air conditioner includes a refrigeration cycle in which a first compressor and a second compressor are connected in parallel, and the first compressor, the second compressor, a first outdoor heat exchanger, a second outdoor heat exchanger, a first indoor heat exchanger, a second indoor heat exchanger, and expansion valves are connected. When the air conditioning apparatus is operated in a first operation mode in which the second outdoor heat exchanger and the first indoor heat exchanger are operated as condensers and the second indoor heat exchanger is operated as an evaporator, refrigerant discharged from the first compressor flows through the first indoor heat exchanger, the expansion valves, and the second indoor heat exchanger in order while bypassing the first outdoor heat exchanger and the second outdoor heat exchanger.