Abstract: An air-conditioning apparatus includes a casing provided with an air inlet through which air is sucked and an air outlet through which the air is blown out, heat exchangers being connected in parallel, and causing heat exchange to be performed between the air sucked from the air inlet and refrigerant, fans each sending the air to a corresponding one of the heat exchangers, and a controller. The controller controls the fans so that they have different rotational speeds.

Abstract: A refrigeration cycle apparatus includes a compressor, a four-way valve, a first outdoor heat exchanger, a first expansion valve, and an indoor heat exchanger. The four-way valve includes a casing, a first flow channel, a second flow channel, a flow channel switching piston, and a wall portion. The flow channel switching piston is configured to slide along an inner surface to switch between passing the refrigerant through the first flow channel and passing the refrigerant through the second flow channel. The wall portion is configured to slide along the inner surface together with the flow channel switching piston and is disposed with a space between the flow channel switching piston and wall portion to cover the flow channel switching piston.

Abstract: When a controller performs a defrosting operation in which frost on an outdoor heat exchanger is caused to be melted, the controller is configured to perform a first defrosting control in which a switching state of a switching device is set to a first state, after the controller performs the first defrosting control, perform a second defrosting control in which the switching state of the switching device is set to a second state, and after the controller performs the second defrosting control, perform a third defrosting control in which the switching state of the switching device is set to the first state.

Abstract: A refrigeration cycle apparatus includes: a compressor; an indoor heat exchanger; an outdoor heat exchanger including first and second outdoor heat exchangers; a bypass flow passage causing a discharge side of the compressor to communicate with the first or second outdoor heat exchanger; a flow control valve at the bypass flow passage; and a controller performing a heating operation in which the first and second outdoor heat exchangers operate as an evaporator and the indoor heat exchanger operates as a condenser and a simultaneous heating and defrosting operation in which part of refrigerant the compressor discharges is supplied to one of the first and second outdoor heat exchangers through the bypass flow passage, the other of the outdoor heat exchangers operates as an evaporator, the indoor heat exchanger operates as a condenser, and an upper limit frequency of the compressor changes to a value higher than in the heating operation.

Abstract: An air-conditioning apparatus includes a main circuit in which a compressor, a flow switching device, an indoor heat exchanger, a pressure reducing device, and a plurality of parallel heat exchangers connected in parallel with each other are connected by pipes, a bypass pipe, a flow control device provided to the bypass pipe and configured to adjust a flow rate of refrigerant flowing through the bypass pipe, an evaporating pressure sensor configured to measure an evaporating pressure of the refrigerant, and a controller. The air-conditioning apparatus is configured to operate in a normal heating operation mode and a heating-defrosting operation mode. When an operation associated with the normal heating operation mode is switched to an operation associated with the heating-defrosting operation mode, the controller adjusts an opening degree of the flow control device using the evaporating pressure in the parallel heat exchanger and a driving frequency of the compressor.

Abstract: An air conditioning apparatus includes a refrigerant circuit and a controller. The refrigerant circuit is configured to allow refrigerant to circulate through a compressor, a condenser, an LEV, and an evaporator. The LEV has an opening degree variable from a lower limit opening degree to an upper limit opening degree. The controller is configured to control the LEV to alternately repeat a first opening degree and a second opening degree in a range of less than or equal to a quarter of the upper limit opening degree, the second opening degree being smaller than the first opening degree.

Abstract: A heat exchanger includes a heat transfer tube. The heat transfer tube includes a first tube portion, and second tube portions connected in parallel with each other with respect to the first tube portion. The first tube portion has a first inner circumferential surface, and first grooves recessed relative to the first inner circumferential surface and arranged side by side in a circumferential direction of the heat transfer tube. The second tube portions each have a second inner circumferential surface, and a plurality of second grooves recessed relative to the second inner circumferential surface and arranged side by side in the circumferential direction. The first grooves are less than the second grooves in one or more of a number of grooves, a depth of each groove, and a lead angle of each groove.

Abstract: An air-conditioning apparatus includes a refrigerant circuit including: a compressor; a high-pressure pipe for high-pressure refrigerant discharged from the compressor; a low-pressure pipe for low-pressure refrigerant to be sucked into the compressor; a first flow switching valve; an indoor heat exchanger; an expansion valve, a first outdoor heat exchanger; a second outdoor heat exchanger; and a second flow switching valve. The second flow switching valve switches flow passages for refrigerant flowing to the first outdoor heat exchanger and the second outdoor heat exchanger. The second flow switching valve includes a first chamber, a second chamber, and a slide valve that is moved by a differential pressure between the first and second chambers. At least one of the first and second chambers is connected with the high-pressure pipe or the low-pressure pipe.

Abstract: A refrigeration cycle apparatus includes a heat source unit including a compressor, a flow switching valve, a first heat exchanger, and an expansion valve, an air-conditioning unit including a second heat exchanger and configured to perform air-conditioning, and a hot water supply unit including a third heat exchanger and configured to supply hot water. The flow switching valve includes a first port connected to a discharge port of the compressor, a second port connected to the second heat exchanger, a third port connected to a suction port of the compressor, and a fourth port connected to the first heat exchanger.

Abstract: The refrigeration cycle apparatus includes a refrigerant circuit, a controller to control the refrigerant circuit, a bypass flow path, and a flow control valve. The bypass flow path communicates between the discharge side of the compressor and the first outdoor heat exchanger or between the discharge side of the compressor and the second outdoor heat exchanger. The flow control valve is provided to the bypass flow path. The refrigerant circuit is configured to be able to perform a heating defrosting simultaneous operation. The heating defrosting simultaneous operation is an operation of supplying part of the refrigerant discharged from the compressor to one of the first outdoor heat exchanger and the second outdoor heat exchanger via the bypass flow path, causing the other of the first outdoor heat exchanger and the second outdoor heat exchanger to serve as an evaporator, and causing the indoor heat exchanger to serve as a condenser.

Abstract: A gas-liquid separation device comprises a container, an inlet tube, a liquid outlet tube, a gas outlet tube, and a swirl vane. The swirl vane is disposed in the inlet tube. A depression is provided on an inner circumferential surface of the inlet tube. The depression faces the swirl vane.

Abstract: An air-conditioning apparatus includes a casing provided with an air inlet through which air is sucked and an air outlet through which the air is blown out, a plurality of heat exchangers being connected in parallel, and causing heat exchange to be performed between the air sucked from the air inlet and refrigerant, a plurality of fans each sending the air to a corresponding one of the plurality of heat exchangers, and a controller configured to control the plurality of fans so that they have different rotational speeds.

Abstract: A refrigeration cycle apparatus includes: a compressor; an indoor heat exchanger; an outdoor heat exchanger including first and second outdoor heat exchangers; a bypass flow passage causing a discharge side of the compressor to communicate with the first or second outdoor heat exchanger; a flow control valve at the bypass flow passage; and a controller performing a heating operation in which the first and second outdoor heat exchangers operate as an evaporator and the indoor heat exchanger operates as a condenser and a simultaneous heating and defrosting operation in which part of refrigerant the compressor discharges is supplied to one of the first and second outdoor heat exchangers through the bypass flow passage, the other of the outdoor heat exchangers operates as an evaporator, the indoor heat exchanger operates as a condenser, and an upper limit frequency of the compressor changes to a value higher than in the heating operation.

Abstract: A refrigeration cycle apparatus includes a compressor, a four-way valve, a first outdoor heat exchanger, a first expansion valve, and an indoor heat exchanger. The four-way valve includes a casing, a first flow channel, a second flow channel, a flow channel switching piston, and a wall portion. The flow channel switching piston is configured to slide along an inner surface to switch between passing the refrigerant through the first flow channel and passing the refrigerant through the second flow channel. The wall portion is configured to slide along the inner surface together with the flow channel switching piston and is disposed with a space between the flow channel switching piston and wall portion to cover the flow channel switching piston.

Abstract: A refrigeration cycle apparatus includes a first flow switch valve including first to fourth ports, a second flow switch valve and a third flow switch valve each including fifth to seventh ports, a compressor, a discharge pipe connecting a discharge port of the compressor and the first port, a first high pressure pipe connecting between the discharge pipe and the fifth ports, a bypass expansion valve provided at a part of the first high pressure pipe, the part extending, a first outdoor heat exchanger connected to the seventh port of the second flow switch valve, a second outdoor heat exchanger connected to the seventh port of the third flow switch valve, and a controller. The controller is configured to perform a differential pressure ensuring process, when switching the second flow switch valve or the third flow switch valve.

Abstract: An outdoor unit includes a casing including an air passage, an outdoor fan disposed in the air passage, a compressor disposed in the casing, an outdoor heat exchanger disposed in the casing and including fins and a heat transfer tube connected to the fins, a control board disposed in the casing and including a control unit that controls the compressor, and a heat sink disposed in the air passage in the casing and being in contact with the control board. The heat transfer tube of the outdoor heat exchanger includes a first region in which gas refrigerant or two-phase gas-liquid refrigerant flows when the outdoor heat exchanger is used as a condenser and a second region that is located downstream of the first region in a refrigerant flow direction and in which single-phase liquid refrigerant flows.

Abstract: In a refrigeration cycle apparatus according to the present disclosure, the circulation direction of refrigerant is switched between a first circulation direction and a second circulation direction opposite to the first circulation direction. The first circulation direction is a circulation direction in order of a compressor, a first heat exchanger, a first expansion valve, a third heat exchanger, a fourth heat exchanger, a second expansion valve, and a second heat exchanger. When a circulation direction of the refrigerant is the first circulation direction, the refrigerant from the third heat exchanger exchanges heat with the refrigerant from the second heat exchanger in the fourth heat exchanger. When a circulation direction of the refrigerant is the second circulation direction, the refrigerant from the fourth heat exchanger exchanges heat with the refrigerant from the first heat exchanger in the third heat exchanger.

Abstract: An air-conditioning apparatus includes a main circuit in which a compressor, a flow switching device, an indoor heat exchanger, a pressure reducing device, and a plurality of parallel heat exchangers connected in parallel with each other are connected by pipes, a bypass pipe, a flow control device provided to the bypass pipe and configured to adjust a flow rate of refrigerant flowing through the bypass pipe, an evaporating pressure sensor configured to measure an evaporating pressure of the refrigerant, and a controller. The air-conditioning apparatus is configured to operate in a normal heating operation mode and a heating-defrosting operation mode. When an operation associated with the normal heating operation mode is switched to an operation associated with the heating-defrosting operation mode, the controller adjusts an opening degree of the flow control device using the evaporating pressure in the parallel heat exchanger and a driving frequency of the compressor.

Abstract: An air-conditioning apparatus includes a refrigerant circuit in which a compressor, an indoor heat exchanger, a first expansion device, an outdoor heat exchanger, and a flow switching device are sequentially connected to each other; a hot gas bypass pipe coupling a discharge port of the compressor and the flow switching device to each other; and a controller. The outdoor heat exchanger includes an upper heat exchanger and a lower heat exchanger having passages in parallel with each other. The outdoor heat exchanger includes a plurality of hairpin pipes, which are part of a heat transfer pipe. When the upper heat exchanger is defrosted, all hairpin pipes that are located at a lowermost step of the upper heat exchanger are used as refrigerant inlets. When the lower heat exchanger is defrosted, all hairpin pipes that are located at an uppermost step of the lower heat exchanger are used as refrigerant inlets.

Abstract: A heat exchanger includes a heat transfer tube. The heat transfer tube includes a first tube portion, and a plurality of second tube portions connected in parallel with each other with respect to the first tube portion. The first tube portion has a first inner circumferential surface, and a plurality of first grooves recessed relative to the first inner circumferential surface and arranged side by side in a circumferential direction of the heat transfer tube. The plurality of second tube portions each have a second inner circumferential surface, and a plurality of second grooves recessed relative to the second inner circumferential surface and arranged side by side in the circumferential direction. The plurality of first grooves are less than the plurality of second grooves in at least one of a number of grooves, a depth of each groove, and a lead angle of each groove.