Some embodiments of the present disclosure provide a heat exchange flat tube and a heat exchanger. The heat exchange flat tube includes: a first plate body; a second plate body, which is disposed opposite to the first plate body, a fluid channel is formed between the second plate body and the first plate body, and the fluid channel is provided with an inlet and an outlet; a throttling structure is disposed between the first plate body and the second plate body, the throttling structure communicates with the fluid channel, the throttling structure is located at the inlet, and the throttling structure includes a plurality of bent sections which communicate in sequence.

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.

A heat exchanger exchanges heat between refrigerant flowing inside and air flowing outside. The heat exchanger includes: an upstream-side flat tube; downstream-side flat tubes on a downstream side of the upstream-side flat tube in a direction of air flow; and a space formation member that defines a distribution space in which the refrigerant coming out of the upstream-side flat tube is distributed to the downstream-side flat tubes.

A heat exchanger includes: a heat exchange element including flat tubes spaced from each other; and a first header in which one end portion of each of the flat tubes is inserted. The first header includes: a first main header portion in which some of the flat tubes are inserted; a first sub-header portion in which others of the flat tubes are inserted such that the number of the flat tubes inserted in the first sub-header portion is smaller than that of the flat tubes inserted in the first main header portion; and a partition plate provided between the first main header portion and the first sub-header portion, and joined to the first main header portion and the first sub-header portion. The partition plate has a surface area that is larger than a sectional area of the first main header portion and a sectional area of the first sub-header portion.

A heat exchanger assembly (100), the heat exchanger assembly (100) comprising: a first heat exchanger (1), the first heat exchanger (1) comprising a first communicating header pipe (10), a first header pipe (12), and heat exchange tubes (9) arranged between the first communicating header pipe (10) and the first header pipe (12); and a second heat exchanger (2), the second heat exchanger (2) comprising a second communicating header pipe (20), a second header pipe (22), and heat exchange tubes (9) arranged between the second communicating header pipe (20) and the second header pipe (22), wherein the first communicating header pipe (10) is provided with a partition plate (30) and thus has a plurality of first communicating chambers (14) arranged in the axial direction of the first communicating header pipe (10), the second communicating header pipe (20) is provided with a partition plate (30) and thus has a plurality of second communicating chambers (24) arranged in the axial direction of the second communicating header pipe (20), and the plurality of first communicating chambers (14) are in fluid communication with the corresponding plurality of second communicating chambers (24), such that a refrigerant entering the heat exchanger assembly (100) successively enters the second heat exchanger (2) and the first heat exchanger (1) in series. The heat exchange capability of the heat exchanger assembly (100) can be effectively improved.

An air-conditioning apparatus includes: a compressor, a first heat exchanger, an expansion unit and a second heat exchanger that are connected, by a pipe, in a refrigerant circuit through which refrigerant flows, wherein the first heat exchanger includes: a radiator fin, multiple tubes extending through the radiator fin and through which the refrigerant flows, and a side plate provided at end portions of the multiple tubes, and having multiple holes formed thereon, through which the multiple tubes are extended, wherein, on the side plate, between the holes corresponding to the multiple tubes to be connected, a marking corresponding to a type of a connection member that connects the multiple tubes is provided.

An HVAC heat exchanger with an array of tubes including one or more dead tubes is provided. In one embodiment, the heat exchanger is a microchannel heat exchanger operable to exchange heat with air in an HVAC system via refrigerant passing through the microchannel heat exchanger. The microchannel heat exchanger includes an array of flat tubes arranged between a first manifold and a second manifold. The array of flat tubes includes multiple tubes coupled in fluid communication with the first manifold and the second manifold to convey refrigerant between the first manifold and the second manifold through microchannels of the multiple tubes. The array of flat tubes also includes one or more dead tubes that do not convey refrigerant between the first manifold and the second manifold. Additional systems, devices, and methods are also disclosed.

A heat exchanger includes a plurality of principal heat exchange sections and auxiliary heat exchange sections. Each of the auxiliary heat exchange sections is in series connection to a corresponding one of the principal heat exchange sections. Of tube number ratios of the number of the flat tubes constituting each of the heat exchange sections to the number of the flat tubes constituting a corresponding one of the auxiliary heat exchange sections, the first principal heat exchange sections which is the lowermost one has the smallest tube number ratio. Consequently, discharge of liquid refrigerant from a lower portion of the first principal heat exchange section is accelerated during defrosting, thereby shortening the time required for defrosting.

Heat exchanger comprising a pair of headers and a plurality of parallel and coplanar tubes interconnecting the headers, wherein each header comprises a header plate provided with a plurality of slots, in each of which an end of a respective tube is fitted, and wherein the heat exchanger is configured to prevent fluid from flowing into at least one tube, hereinafter dummy tube, arranged at a boundary between functionally different sections of the heat exchanger. The slot of the header plate which receives the end of the respective dummy tube is formed as a blind recess in the header plate.

Low head loss systems are detailed. The systems may include chambers having low impedance to water flow therethrough and repositionable gates or other valves within the chambers. The valves may direct water as a function of whether an associated heating device is active. At least some gates may incorporate poppet valves or other high-flow by-passes.