An air-conditioning apparatus includes a compressor for compressing and discharging refrigerant; an outdoor heat exchanger for exchanging heat between the refrigerant and a heat medium that enters the outdoor heat exchanger; an indoor heat exchanger for exchanging heat between the refrigerant and a surrounding medium of use; a bypass pipe for bypassing the refrigerant that is to enter the outdoor heat exchanger; and a bypass flow control valve arranged on the bypass pipe, for adjusting a flow of the refrigerant that is to enter the outdoor heat exchanger, in which the outdoor heat exchanger includes a first passage through which the refrigerant flows, and a second passage through which the heat medium flows, and in which the first passage allows the refrigerant to flow upward.

At a refrigeration cycle device, an injection pipe and an economizer heat exchanger are provided at a main refrigerant circuit. In addition, the refrigeration cycle device includes a sub-refrigerant circuit having a sub-usage-side heat exchanger. At the refrigeration cycle device, the sub-usage-side heat exchanger functions as an evaporator of a sub-refrigerant and cools a main refrigerant that has been cooled at the economizer heat exchanger, or functions as a radiator of the sub-refrigerant and heats the main refrigerant that has been cooled at the economizer heat exchanger.

An air-conditioning apparatus includes a heat source unit, a plurality of indoor units, and a relay unit. The heat source unit includes a heat-source-side flow control valve connected to a heat-source-side heat exchanger, a bypass pipe connected in parallel to the heat-source-side heat exchanger, a bypass flow control valve provided in the bypass pipe, and a gas-liquid separating unit configured to, when refrigerant flows out to the high-pressure pipe, mix refrigerant in a liquid state flowing through the heat-source-side heat exchanger and refrigerant in a gas state flowing through the bypass pipe and cause mixed refrigerant to flow out to the high-pressure pipe, and configured to, when refrigerant flows in from the low-pressure pipe, separate the refrigerant flowing in from the low-pressure pipe into refrigerant in a liquid state flowing into the heat-source-side heat exchanger and refrigerant in a gas state flowing into the bypass pipe.

An air conditioner of the present invention includes: an outdoor unit having an outdoor heat exchanger and a compressor installed therein; a plurality of indoor units connected to the outdoor unit and having an indoor heat exchanger installed therein; a four-way valve provided on a discharge part side of the compressor; a refrigerant tube having first to third refrigerant tubes and connecting the four-way valve and the indoor heat exchanger, in which the first refrigerant tube is branched from between the four-way valve and the outdoor heat exchanger such that some of a refrigerant discharged from the compressor is fed into the indoor heat exchanger while bypassing the outdoor heat exchanger, the second refrigerant tube is connected to the four-way valve to feed all of the refrigerant discharged from the compressor into the indoor heat exchanger, and the third refrigerant tube is connected to the second refrigerant tube in parallel; and a heat pump valve provided at the third refrigerant tube to selectively close the third refrigerant tube. The air conditioner includes an outdoor unit that can be applied to simultaneous cooling and heating concurrent type air conditioners and cooling and heating switching type air conditioners through the opening and closing of the heat pump valve.

An air conditioning system may include an outdoor device disposed in an outdoor space, the outdoor device including a compressor and an outdoor heat exchanger, a plurality of indoor devices disposed in an indoor space, the plurality of indoor devices including an indoor heat exchanger, and a distributor that distributes and introduces a refrigerant into the plurality of indoor devices. The outdoor device may include an outdoor branch branched into a plurality of refrigerant paths, a first outdoor tube that extends from the outdoor branch to guide the refrigerant to a first heat exchanger of the outdoor heat exchanger, a second outdoor tube that extends from the outdoor branch to guide the refrigerant to a second heat exchanger of the outdoor heat exchanger, and a bypass tube that extends from the outdoor branch to allow the refrigerant to bypass the outdoor heat exchanger, thereby guiding the refrigerant to the compressor.

An outdoor unit of an air conditioner coupled to an indoor unit by a liquid pipe and a gas pipe, includes: a compressor; an outdoor heat exchanger; a discharge pipe coupled to a refrigerant discharge side of the compressor; an intake pipe coupled to a refrigerant intake side of the compressor; an outdoor-unit high-pressure gas pipe coupled to the discharge pipe; an outdoor-unit low-pressure gas pipe coupled to the intake pipe; an outdoor-unit liquid pipe that couples a first refrigerant entry/exit opening of the outdoor heat exchanger and the liquid pipe together; a bypass pipe coupled to the outdoor-unit liquid pipe; a first flow-passage switcher coupled to a second refrigerant entry/exit opening of the outdoor heat exchanger, the discharge pipe, the intake pipe, and the bypass pipe; and a second flow-passage switcher coupled to the gas pipe, the outdoor-unit high-pressure gas pipe, and the outdoor-unit low-pressure gas pipe.

An outdoor unit for a multi-type air conditioner includes a compressor, a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, a liquid tank, an accumulator, a shutoff valve provided for the refrigerant pipe between a liquid refrigerant inlet/outlet port and the liquid tank in the outdoor unit, and a first bypass circuit provided in the refrigerant pipe for bypassing the shutoff valve through a capillary tube to connect a liquid refrigerant inlet/outlet port side to an upper side of the refrigerant pipe in a gravity direction. The outdoor unit further includes a second bypass circuit for connecting a bottom portion of the liquid tank to an inlet side of the accumulator via an electromagnetic valve.

An air conditioner is provided that may include at least one compressor that compresses a refrigerant to a high pressure; a plurality of heat exchanger that condenses the refrigerant compressed in the at least one compressor; a plurality of outdoor valves, respectively, provided at an outlet side pipe of the plurality of heat exchangers; a gas liquid separator that separates the refrigerant into gas and liquid refrigerants and supplies the gas refrigerant to the at least one compressor; and one or more bypass devices connected to the outlet side pipe of one or more of the plurality of heat exchangers and an inlet side pipe of the gas liquid separator, the one or more bypass devices controlling a flow of the liquid refrigerant. During a cooling low load operation in which a portion of the plurality of heat exchangers is operating, a liquid refrigerant loaded into a heat exchanger of the plurality of heat exchangers, which is not operated, may flow through the one or more bypass device.

An air conditioner operable even in a low-load cooling or heating mode is provided. The air conditioner may include a compressor that compresses a refrigerant, a main outdoor heat exchanger that condenses the refrigerant in a cooling mode and that evaporates the refrigerant in a heating mode, an indoor heat exchanger that evaporates the refrigerant in the cooling mode while condensing the refrigerant in the heating mode, a switch that guides the refrigerant discharged from the compressor to the main outdoor heat exchanger in the cooling mode and that guides the refrigerant discharged from the compressor to the indoor heat exchanger in the heating mode, and a sub outdoor heat exchanger that evaporates a portion of the refrigerant condensed in the main outdoor heat exchanger in a low-load cooling mode and that condenses a portion of the refrigerant discharged from the compressor in a low-load heating mode.

An air conditioner includes a refrigerant circuit and a blower. A refrigerant flow path switching mechanism is configured to be switched to a first switching state to allow refrigerant to flow through a reheater, a first expansion valve, and a cooler in this order in the refrigerant circuit. The refrigerant flow path switching mechanism is configured to be switched to a second switching state to allow the refrigerant to flow through the reheater, the first expansion valve, and the cooler in this order in the refrigerant circuit. The reheater and the cooler are configured to allow air blown by the blower to pass through the cooler and then pass through the reheater during either of the first switching state and the second switching state.