Abstract: An air-conditioning apparatus includes a compressor and an outdoor heat exchanger that operates as an evaporator. A first heat exchange unit of the outdoor heat exchanger includes: first heat transfer tubes extending in an upward/downward direction, and arranged apart from each other in a lateral direction; a first junction pipe extending in the lateral direction, and connected to the lower ends of the first heat transfer tubes; an outflow pipe connected to the first junction pipe at or below a center position of the first junction pipe in the upward/downward direction; second heat transfer tubes extending in the upward/downward direction, and arranged apart from each other in the lateral direction; a first distribution pipe extending in the lateral direction, and connected to the lower ends of the second heat transfer tubes, and a first connection part connecting upper ends of the first heat transfer tubes and upper ends of the second heat transfer tubes.

Abstract: A heat exchanger includes: flat heat exchange tubes each having an elongated cross section and planar outer surfaces that face each other, and each including a fluid flow passage; and corrugated fins each formed in the shape of waves and provided between associated adjacent ones of the heat exchange tubes. The corrugated fins each having ridge portions that correspond to ridges of the waves and that are joined to the associated heat exchange tubes, the corrugated fin having fins that are located between the ridge portions and are arranged in a height direction. The fins include drain slits each of which allows drainage of water on an associated one of the fins, and end portions of the drain slits of adjacent ones of the fins in a horizontal direction are located at different positions in the drain slits, the adjacent fins being adjacent to each other in the height direction.

Abstract: A gas header includes a first tubular portion and a second tubular portion that are integrated with each other. The second tubular portion is provided across the first tubular portion from a plurality of flat pipes in the horizontal direction. The second tubular portion is connected at a position midway in an up-down direction and upper than a center of the second tubular portion in the up-down direction to a refrigerant pipe. A wall between the first tubular portion and the second tubular portion has a first hole opening and extending in the horizontal direction at a portion connected to the refrigerant pipe and a second hole through which the first tubular portion and the second tubular portion communicate with each other at a portion lower than the first hole and having a hole diameter smaller than a hole diameter of the first hole.

Abstract: A heat exchanger has first and second heat exchange units disposed one above the other. In a case where the heat exchanger functions as a condenser, refrigerant flows through the second heat exchange unit after having flowed through the first heat exchange unit. An intermediate header unit through which the first heat exchange unit and the second heat exchange unit communicate with each other causes at least a portion of refrigerant having flowed through a first heat transfer pipe group on the windward side of the first heat exchange unit to flow to a fourth heat transfer pipe group. Further, the intermediate header unit causes at least a portion of refrigerant having flowed through a second heat transfer pipe group on the leeward side of the first heat exchange unit to flow into a third heat transfer pipe group or the fourth heat transfer pipe group.

Abstract: A heat exchanger includes a plurality of heat transfer pipes provided at spacings from each other in a first direction, a header having an insertion hole in which a front end of each of the plurality of heat transfer pipes is inserted from a second direction orthogonal to the first direction, and a fin attached to heat transfer pipes. The header includes a divider configured to divided the inside of the header into a first space in which the insertion hole is provided and a second space to which a refrigerant pipe is connected. The divider is provided with an opening surrounding the outer periphery of the front end of the heat transfer pipe as seen from the second direction. An air-conditioning apparatus includes the heat exchanger as a condenser or an evaporator.

Abstract: A heat exchanger includes plural heat transfer tubes disposed with a specified spacing from each other in the up and down direction, and a distributor configured to distribute refrigerant to the heat transfer tubes. The distributor includes a body part, and plural flow-splitting parts, the body part including a first passage in which refrigerant flows upward, the flow-splitting parts communicating with the first passage and with one of the heat transfer tubes. The flow-splitting parts include one or more first flow-splitting parts each communicating with a first heat transfer tube, which is a higher positioned heat transfer tube. The flow-splitting parts include one or more second heat transfer tubes each communicating with a second heat transfer tube positioned below the first heat transfer tube. The refrigerant inlet of the first flow-splitting part communicates with the first passage at a location below the refrigerant inlet of the second flow-splitting part.

Abstract: A heat exchanger includes: a heat exchange body having a plurality of flat tubes arranged and spaced from each other in a horizontal direction; an upper header provided at an upper end of the heat exchange body; a lower header provided at a lower end of the heat exchange body; and a partition plate provided in at least one of the upper and lower headers to partition the heat exchange body into a plurality of regions in a horizontal direction. The partition plate is provided such that in each of the regions, refrigerant flows in the opposite direction to the flow direction of the refrigerant in an adjacent one of the regions, and is provided such that regarding the regions, the more downward the region in the flow of the refrigerant when the heat exchanger operates as a condenser, the smaller a flow passage cross-sectional area of the region.

Abstract: A heat exchanger includes a plurality of flat tubes, and a header. A flow passage provided inside the header includes a plurality of partition portions each provided between the adjacent flat tubes, a plurality of insertion portions formed between the adjacent partition portions, a first communication passage allowing one ends of the adjacent insertion portions to communicate with each other, and a second communication passage allowing an other ends of the adjacent insertion portions to communicate with each other. A cross-sectional area of the first communication passage is larger than a cross-sectional area of the second communication passage, and the first communication passage is provided with a first refrigerant inlet connected to the flow passage and allowing the refrigerant to flow into the header. Thus, a heat exchanger performance can be improved by reducing a refrigerant pressure loss and by achieving uniform distribution of the refrigerant.

Abstract: A refrigerant distributor includes an outer pipe, an inner pipe, and a structural part. The refrigerant outflow hole is provided such that an angle ? between a lower end of the inner pipe on a vertical line passing through a center of the inner pipe and a position of presence of the refrigerant outflow hole as seen from the center of the inner pipe falls within a range of 10 degrees???80 degrees. The refrigerant outflow hole comprises a sole refrigerant outflow hole provided in a vertical cross-section of the inner pipe at a position where the refrigerant outflow hole is provided.

Abstract: A heat exchanger includes a plurality of flat tubes in which refrigerant flows and a plurality of fins provided between the plurality of flat tubes and configured to transfer heat of refrigerant flowing in the plurality of flat tubes. An upstream end portion of each of the plurality of flat tubes in an air flow direction is located at the same position as an upstream end portion of each of the plurality of fins or protrudes farther than the upstream end portion of each of the plurality of fins, and an opening port is formed at the upstream end portion of each of the plurality of flat tubes or at the upstream end portion of each of the plurality of fins.

Abstract: An air-sending device includes a housing including an inlet air passage communicating with an air inlet and an outlet air passage communicating with an air outlet, a first partition plate partitioning an interior of the housing into the inlet air passage and the outlet air passage, a bell mouth disposed around an opening defined in the first partition plate, and an impeller disposed over the first partition plate across the bell mouth and having a rotation axis that extends in a direction that intersects the first partition plate. The impeller suctions air into the inlet air passage from the air inlet, and blows out air from the air outlet through the outlet air passage. The inlet air passage guides air from the air inlet to the opening along the first partition plate, and has an air-passage wall.

Abstract: A header includes a plurality of branch tubes and a header manifold. If refrigerant flowing into the header manifold forms a pattern of annular flow or churn flow, tips of the branch tubes inserted into the header manifold pass through a liquid-phase portion having a thickness ? [m] and reach a gas-phase portion. The thickness ? [m] of the liquid-phase portion is defined as ?=G×(1?x)×D/(4?L×ULS), where G is a flow speed [kg/(m2 s)] of the refrigerant, x is a quality of the refrigerant, D is an inside diameter [m] of the header manifold, ?L is a liquid density [kg/m3] of the refrigerant, ULS is a reference apparent liquid speed [m/s] that is a maximum value within a range of variation in an apparent gas speed of the refrigerant flowing into a flow space of the header manifold. The reference apparent liquid speed ULS [m/s] is defined as G(1?x)/?L.

Abstract: An air-conditioning apparatus includes: a housing having an intake air passage communicating with an air inlet and a blowout air passage communicating with an air outlet that allows air to be blown out in a single direction; a fan; a front heat exchanger facing the air outlet of the housing and including first and second heat exchangers; and at least one of rear and side heat exchangers that face rear and side surfaces of the housing, respectively. When the front heat exchanger operates as a condenser, the first heat exchanger operates as a condenser, and condensed and liquified refrigerant flows in the second heat exchanger. The second heat exchanger is located downstream of the first heat exchanger and the at least one of the rear and side heat exchangers in the flow direction of a refrigerant.

Abstract: A heat exchange unit includes a housing having an inflow air passage communicating with an air inlet, and an outflow air passage communicating with an air outlet, a first partition plate that partitions an inside of the housing into the inflow air passage and the outflow air passage, a bellmouth disposed around an opening formed in the first partition plate, a centrifugal fan disposed on the first partition plate via the bellmouth, and a heat exchanger disposed on a downstream side of the centrifugal fan in the housing. The air inlet is open at any surface of the housing having the inflow air passage. The air outlet is open at any side surface of the housing having the outflow air passage. The inflow air passage is formed between a fan inlet and a main plate closest to the fan inlet to reach a rear surface. The fan inlet is an air inlet of the centrifugal fan.

Abstract: The air-conditioning apparatus includes a heat exchanger including a plurality of heat transfer tubes and a header manifold an axial fan and a refrigerant circuit. When the distance from the center of the flow space in the horizontal plane is represented on a scale of 0 to 100%, where 0% represents the center of the flow space and 100% is the position of the wall surface of the header manifold, among the plurality of branch tubes located within a height range that allows the blade to rotate, the majority of the branch tubes located at or below the height of the boss are connected to the header manifold such that their distal ends are positioned at 0 to 50% of the distance from the center, and the majority of the branch tubes located above the height of the boss are connected to the header manifold such that their distal ends are positioned at more than 50% of the distance from the center.

Abstract: A heat exchanger includes heat transfer tubes disposed in an up-down direction and a distributor distributes refrigerant to the heat transfer tubes. The distributor has a main body having a first flow passage through which refrigerant flows upward, and an insertion part disposed inside the main body. When an upper one and a lower one of two among the heat transfer tubes are a first heat transfer tube and a second heat transfer tube, respectively, the insertion part is installed between the first heat transfer tube and the second heat transfer tube. The main body has a second flow passage through which refrigerant flows upward. Refrigerant having passed through the first flow passage and the second flow passage flows through the first heat transfer tube, and refrigerant having passed through the first flow passage flows through the second heat transfer tube.

Abstract: An outdoor unit of an air-conditioning apparatus includes a heat exchange body including a plurality of flat tubes that extend in a vertical direction and that are arranged in a horizontal direction with gaps therebetween. A plurality of the heat exchange bodies are arranged in a direction of air flow to form a heat exchanger. A first header, into which hot gas refrigerant flows from a refrigerant circuit, is provided below one of the plurality of the heat exchange bodies that is at a most upwind position.

Abstract: A heat exchanger includes a tubular refrigerant distributor having insertion holes spaced from each other in a first direction and into which ends of heat transfer tubes are inserted in a second direction. A first partition plate partitions the refrigerant distributor into a first space into which the ends of the heat transfer tubes are inserted and a second space, larger than the first space, into which the ends of the heat transfer tubes are not inserted; and an inflow pipe provided on a one side-surface side of the refrigerant distributor. The heat transfer tubes are located apart from the first partition plate in the first space. The first partition plate is provided with an orifice that is provided at a location corresponding to a space between adjacent ones of the heat transfer tubes, and that causes the first space and the second space to communicate with each other.

Abstract: An outdoor unit according to the present disclosure includes: a compressor that sucks refrigerant, compresses the sucked refrigerant, and discharges the compressed refrigerant; a first refrigerant flow switching device that switches a flow passage for the refrigerant between a flow passage for a cooling operation and a flow passage for a heating operation; a heat-source-side heat exchanger that causes heat exchange to be performed between the refrigerant and external fluid; a heat-source-side backflow prevention device and a connection pipe that are included in a flow passage for the refrigerant in which an outlet from which the refrigerant flows to an outside region and an inlet into which the refrigerant flows from the outside region are unchanged regardless of which of the cooling operation and the heating operation is performed; and a flow passage pipe through which part of the refrigerant having flowed from the inlet passes in the cooling operation.

Abstract: An air-conditioning apparatus includes a compressor and an outdoor heat exchanger that operates as an evaporator. A first heat exchange unit of the outdoor heat exchanger includes: first heat transfer tubes extending in an upward/downward direction, and arranged apart from each other in a lateral direction; a first junction pipe extending in the lateral direction, and connected to the lower ends of the first heat transfer tubes; an outflow pipe connected to the first junction pipe at or below a center position of the first junction pipe in the upward/downward direction; second heat transfer tubes extending in the upward/downward direction, and arranged apart from each other in the lateral direction; a first distribution pipe extending in the lateral direction, and connected to the lower ends of the second heat transfer tubes, and a first connection part connecting upper ends of the first heat transfer tubes and upper ends of the second heat transfer tubes.