Systems and methods for attaching heat exchangers about tanks of water heaters

Abstract

A water heater including a water tank configured to store water is disclosed. The water heater may further include a heat source configured to provide heat to a heat transfer fluid and a heat exchanger in fluid communication with the heat source. The heat exchanger may include a header and a plurality of microchannels attached to the header. The plurality of microchannels may be wrapped around the water tank using the header, and the plurality of microchannels may be configured to circulate the heat transfer fluid via the header to transfer heat to the water tank. Each microchannel may be wrapped around the header from a header back surface.

Description

SYSTEMS AND METHODS FOR ATTACHING HEAT EXCHANGERS ABOUT TANKS OF WATER HEATERSCROSS-REFERENCE TO RELATED APPLICATIONS OOOll The present application claims priority to and the benefit of US provisional application No. 63 / 518,202, file August 8, 2023, which is hereby incorporated by reference herein in its entirety.FIELD[0002J The present disclosure relates to water heaters and more specifically to systems and methods for attaching heat exchangers about tanks of water heaters.BACKGROUND

[6003] Water heaters are generally used to provide a supply of heated water in a variety7of applications, including residential, commercial, and industrial applications. Conventional water heaters use gas burners, electrical heating elements, heat pumps, and / or solar panels (or other renewable sources) to heat water. For example, a heat pump water heater may draw heat from ambient air to transfer heat to a refrigerant, which in turn may heat water stored in a tank of a water heater.

[0004] Some modem water heaters include microchannels that are used to circulate the refrigerant around the tank of the water heater to heat water therein. In some instances, the microchannels are wrapped around the water tank to enable transfer of heat from the refrigerant to the water stored in the water tank.[00051 There are known instances of a gap being created or present between the surfaces of the microchannels and the water tank when the microchannels are wrapped around the water tank by using headers. The presence of the gap may result in accumulation of insulating material (e.g., polyurethane foam) during manufacture of the water heater and / or over time when the water heater may be operated, resulting in reduced heat transfer and water heater thermal performance.BRIEF DESCRIPTION OF THE DRAWINGS[0006^ The detailed description is set forth with reference to the accompanying drawings. The use of the same reference numerals may indicate similar or identical items. Various embodiments may utilize elements and / or components other than those illustrated in the drawings, and some elements and / or components may not be present in various embodiments. Elements and / or components in the figures are not necessarily drawn to scale. Throughout this disclosure, depending on the context, singular and plural terminology may be used interchangeably.[0007^ FIG. 1 depicts an isometric view of a water heater in accordance with one or more embodiments of the present disclosure.[0008| FIG. 2 depicts a top view of the water heater of FIG. 1 in accordance with one or more embodiments of the present disclosure.

[0009] FIG. 3 depicts an interaction of microchannels in a header in accordance with one or more embodiments of the present disclosure.

[0010] FIG. 4 depicts an isometric view of another water heater in accordance with one or more embodiments of the present disclosure.

[0011] FIG. 5 depicts a flow diagram of an example method to dispose a plurality of microchannels in a water heater in accordance with one or more embodiments of the present disclosure.|0012] FIG. 6 depicts example stages of manufacturing a microchannel in accordance with one or more embodiments of the present disclosure.DETAILED DESCRIPTION[0013 The present disclosure is directed towards a water heater having a water tank configured to store water therein. In certain embodiments, the water heater may include a heat source (such as a heat pump or the like) that may be configured to heat water in the water tank. In some aspects, the heat source may be configured to provide heat to a heat transfer fluid (such as a refrigerant), which may flow in a heat exchanger. In certain embodiments, the heat exchanger may be wrapped around a water tank exterior surface and may be configured to transfer heat from the refrigerant to the water inside the water tank.

[0014] In some instances, the heat exchanger may include a first header, a second header, and a plurality of fluid channels (e.g., microchannels) that may be wrapped aroundthe water tank by between the first header and the second header. In some aspects, each microchannel of the plurality of microchannels may be a cuboidal-shaped tube that may be disposed about the water tank such that a predetermined spacing or distance may exist between adjacent microchannels.|O015] In certain embodiments, each microchannel may have a first end (e.g., an inlet end) and a second end (e.g., an outlet end). A fluid conduit may be formed between the first end and the second end. In some instances, the first end of each microchannel may be at least partially circumferentially wrapped around the first header, and the second end of each microchannel may be at least partially circumferentially wrapped around the second header. Specifically, each microchannel may be circumferentially wrapped around the first header and the second header via respective header back surfaces such that a contact surface (i.e., a surface area of the microchannel against the exterior surface of the water tank) may increase. In some instances, the surface may be flat. By increasing the contact surface, as described in the present disclosure, a gap that existed between the microchannel and the water tank due to the connection between the microchannel and the first / second header in conventional water heaters may be eliminated and / or substantially reduced. Since the gap is eliminated and / or substantially reduced, insulating material / foam that typically accumulated within the gap may not do so, which may result in enhanced water heater performance.The first header and the second header each may be a hollow conduit (e.g., tube) that may facilitate refrigerant circulation in the plurality of microchannels to heat the water in the water tank. In some aspects, the first header and the second header may include one or more guiding mechanisms / restrictions (such as baffles) to direct the flow of refrigerant in a predetermined manner or pattern to increase water heating efficiency. For example, the refrigerant may enter the first header (as an example), circulate through a microchannel (or a set of microchannels), and enter the second header. The refrigerant may then move in a predefined direction (e.g., down) in the second header and circulate through another microchannel (or another set of microchannels) and then enter the first header. In this manner, the refrigerant may circulate through the plurality of microchannels via the first and second headers.[GO37| In some aspects, each microchannel may have a tapered end, for example, a tapered inlet end and a tapered outlet end, which may enable the refrigerant to efficientlyflow between adjacent microchannels. The tapered ends of adjacent microchannels may be positioned such that the tapered ends form a predetermined angle. 00!8| Although certain examples of the disclosed technology are explained in detail herein, it is to be understood that other examples, embodiments, and implementations of the disclosed technology are contemplated. Accordingly, it is not intended that the disclosed technology is limited in its scope to the details of construction and arrangement of components expressly set forth in the following description or illustrated in the drawings. The disclosed technology can be implemented in a variety of examples and can be practiced or carried out in various ways. In particular, the presently disclosed subject matter is described in the context of being a system and method for heating water with a heat pump and microchannel heat exchanger. The present disclosure, however, is not so limited, and can be applicable in other contexts. The present disclosure, for example and not limitation, can be applied to heating water with heating sources. Furthermore, the present disclosure can include other fluid heating systems configured to heat a fluid other than water such as process fluid heaters used in industrial applications. Such implementations and applications are contemplated within the scope of the present disclosure. Accordingly, when the present disclosure is described in the context of being a system and method for heating water with a heat pump and microchannel heat exchanger, it will be understood that other implementations can take the place of those referred to.Although the term “water’ is used throughout this specification, it is to be understood that other fluids may take the place of the term “water” as used herein. Therefore, although described as a system and method to heat water, it is to be understood that the system and method described herein can apply to fluids other than water. Further, it is also to be understood that the term “water” can replace the term “fluid” as used herein unless the context clearly dictates otherwise.|W20] Turning now to the drawings, FIG. 1 depicts an isometric view of a water heater 100 in accordance with one or more embodiments of the present disclosure. The water heater 100 may include a water storage tank 102 for storing water.[0021 The water storage tank 102 may be of any size, shape, or configuration based on the water heating device application. For example, the water storage tank 102 may be sized for common residential use or for commercial or industrial use that may require greater amounts of heated water. Furthermore, the water storage tank 102 can be made of anysuitable material for storing and heating water, including copper, carbon steel, stainless steel, ceramics, polymers, composites, or any other suitable material. The water storage tank 102 can also be treated or lined with a coating to prevent corrosion and leakage. A suitable treating or coating will be capable of withstanding the temperature and pressure of the water heater 100 and can include, as non-limiting examples, glass enameling, galvanizing, thermosetting resin-bonded lining materials, thermoplastic coating materials, cement coating, or any other suitable treating or coating for the application. In some aspects, the water storage tank 102 may be insulated to retain heat. For example, the water storage tank 102 may be insulated using an insulating material like polyurethane foam. [00221 The water heater 100 may include a water inlet (not shown) to receive water (e.g., tap water or water from a utility source) in the water storage tank 102. The water heater 100 may additionally include a water outlet (not shown) to output heated water from the w aler storage tank 102.

[0023] The w ater heater 100 may further include a heat source (not shown) configured to heat water in the water storage tank 102. In an exemplary aspect, the heat source may include a heat pump (or heat pump assembly). In further aspects, the heat source may include a solar heating unit or any other heating source. Any suitable heating source may be used herein.

[0024] The heat pump may include an evaporator, a compressor, a heat exchanger / condenser (including a heat exchanger 104 that may be externally wrapped around the water storage tank 102) and an expansion valve connected in series by refrigerant tubing 106 through which, during heat pump operation, a refrigerant may flow. Specifically, the refrigerant may sequentially flow' from a compressor outlet, through the heat exchanger 104, through the expansion valve, through the evaporator, and back to a compressor inlet. The refrigerant may be any suitable refrigerant, for example, R22 or R410A. The evaporator, the compressor, and the expansion valve of the water heater 100 may be conventional evaporator, compressor, and expansion valve and hence their functions are not described here in detail.

[0025] The heat exchanger 104 may be generally circumferential in shape (e.g., relative to the storage tank 102) and may include a first header 108a and a second header 108b. In certain embodiments, the first header 108a and the second header 108b may be hollow elongated cylindrical tubes. In some aspects, the first header 108a and the second header108b may be disposed on a water storage tank exterior surface, and a longitudinal axis of the first header 108a and the second header 108b may be parallel to a water storage tank longitudinal axis. Further, the first header 108a and the second header 108b may be disposed at a predetermined distance “D” from each other, as shown in FIG. 1. In additional aspects, the first header 108a and the second header 108b may be attached or fastened with each other via a locking mechanism (not shown) to attach the heat exchanger 104 about the water storage tank 102. In some aspects, a first header length and a second header length may be substantially the same as or less than a water storage tank length.[0026^ The heat exchanger 104 may further include a plurality of microchannels 110a, 110b, 110c, etc. (collectively referred to as a plurality of microchannels 110). Each microchannel of the plurality’ of microchannels 110 may be a cuboidal tube having ports (e.g., ports 120 described below) that provide passage for the refrigerant. The plurality of microchannels 110 may be wrapped around the w ater storage tank 102 and may be attached to the first header 108a and the second header 108b (e.g., as discussed below, each microchannel of the plurality of microchannels 110 may be wrapped externally around the first header 108a and the second header 108b). Stated another way. the first header 108a and the second header 108b may be configured to secure the plurality’ of microchannels 110 around the water storage tank 102. Specifically, one end (e.g., a first end) of each microchannel of the plurality' of microchannels 110 may be attached to a header (e.g., the first header 108a) and the other end (e.g., a second end) of each microchannel of the plurality of microchannels 110 may be attached to the other header (e.g., the second header 108b). In this manner, each microchannel of the plurality of microchannels 1 10 is attached to both the first header 108a and the second header 108b and wrapped around the w ater storage tank exterior surface. Stated another way, both the ends of each microchannel of the plurality of microchannels 110 may be wrapped around the first header 108a and the second header 108b, respectively.|(H>27] In certain embodiments, the plurality’ of microchannels 110 may be generally cylindrical in shape and / or C-shaped. In some aspects, the plurality of microchannels 110 may be attached to the first header 108a and the second header 108b by welding and / or using adhesive or any other fastening mechanism to form a fluid tight connection. The attachment of the first header 108a, the second header 108b, and the plurality’ of microchannels 110 is described in detail in conjunction with FIG. 2.In certain embodiments, each microchannel of the plurality7of microchannels 110 may have a flattened top surface 112 and a flattened bottom surface 114. as shown in view 116. Stated another way, a plane (e.g., X-Y plane) of the top surface 112 may be parallel to a plane (e.g., X-Y plane) of the bottom surface 1 14. The flattened top and bottom surfaces 112, 114 may be attached to each other via microchannel side walls 118 such that a predetermined small distance may exist between the flattened top and bottom surfaces 112, 114 to form a fluid conduit. The refrigerant may flow through the predetermined small distance present in each microchannel of the plurality of microchannels 110 when the refrigerant may be circulated through the plurality7of microchannels 110.[0029J In some aspects, each microchannel of the plurality7of microchannels 110 may include ports 120 (e.g., inlet / outlet ports at the ends of each microchannel of the plurality of microchannels 110) that may enable the microchannel of the plurality of microchannels 110 to receive the refrigerant from the first header 108a (and / or the second header 108b) and circulate the refrigerant through the fluid conduit and around the water storage tank exterior surface. In an exemplary aspect, a count of ports in each microchannel of the plurality of microchannels 110 may be in a range of 16 to 32, which may enable the microchannel of the plurality of microchannels 110 to efficiently receive the refrigerant from the first header 108a (and / or the second header 108b). The plurality7of microchannels 110 may be made using an extrusion process or folding process. <I030 As depicted, the plurality of microchannels 110 may be grouped together in bands that are wrapped around the water storage tank 102. The plurality of microchannels 110 may be cuboidal tubes of predetermined thicknesses / widths. In some aspects, the width of each cuboidal tube may be in a range of 12mm - 32mm. In some embodiments, the gap between the top surface 112 and the bottom surface 114 may be in a range of 0.5mm * 0.5mm up to 2mm * 2mm. In other embodiments, the gap between the top surface 112 and the bottom surface 114 may be in a range of 0.5mm * 0.5mm up to 5mm * 5mm. The above-mentioned dimensions are exemplary7and not limiting. Further, each of the bands of the plurality7of microchannels 110 may be disposed at a predetermined distance from adjacent bands of the plurality of microchannels, such a predetermined gap or space “DT’ may exist between adjacent bands of microchannels. In some instances, DI may be in a range of about 12mm to 65mm. DI may be any suitable distance and not limited to the provided range of DI. The plurality of microchannels 110 may be wrapped around thewater storage tank 102 to cover a predetermined length of the water storage tank and may circulate the refrigerant around the water storage tank 102 via the first header 108a and the second header 108b to heat water stored in the water storage tank 1 2. A count of microchannels in the plurality of microchannels 1 10 may depend on the dimensions of the water storage tank and the usage requirements of the water heater. As would be appreciated, increasing the count of microchannels may increase the available surface area on the water storage tank 102 for the heat transfer, thereby increasing water heating capacity / effi ci ency .

[0031] In operation, the first header 108a (and / or the second header 108b) may receive heated refrigerant (e.g., refrigerant in vapor state) from the compressor via the refrigerant tubing 106. The first header 108a (and / or the second header 108b) may transfer the received refrigerant to the plurality of microchannels 110 that may circulate the refrigerant around the water storage tank exterior surface via the first header 108a and the second header 108b. Circulating refrigerant may transfer heat from the refrigerant to the water stored inside the water storage tank 102. thereby heating the water.The first header 108a and the second header 108b may include one or more guiding mechanisms or restrictions 122a, 122b, 122c, 122d, 122e, 122f, etc. (collectively considered as restrictions 122) that may be configured to guide the refrigerant through the plurality of microchannels 110 in a specific pattern. For example, the restrictions 122a and 122d (which may be, for example, baffles) may channelize refrigerant flow through adjacent microchannels 110a and 110b and may prevent the refrigerant from '‘flowing down” without entering respective microchannels ports. In some aspects, the restrictions 122 in the first header 108a and the second header 108b may be positioned to enable the refrigerant to flow through the plurality of microchannels 110 sequentially or in a predetermined order. In some aspects, the restnctions 122 may be disposed in alternate microchannel connection in the first header 108a and the second header 108b, as shown in FIG. 1.

[0033] In an exemplary aspect, the first header 108a may receive the refrigerant via the refrigerant tubing 106 from the compressor (not shown). The refrigerant may then enter a first microchannel 110a via first microchannel ports (and may not move down due to the restrictions 122). The refrigerant may then move in a circular direction (e.g., clockwise direction) around the water storage tank exterior surface, as shown in FIG. 1. Therefrigerant may then enter the second header 108b, move down, and then enter a second microchannel 110b via second microchannel ports (and may not move down due to the restrictions 122). The refrigerant may then move in a counterclockwise direction around the water storage tank 102, as shown in FIG. 1. The refrigerant may then enter the first header 108a and move down to a third microchannel 110c, and so on, to circulate refrigerant through the plurality of microchannels 110.(0034] In another exemplary aspect, the refrigerant may enter the first header 108a, move down and enter in a first set of microchannels (e g., the first microchannel 110a, the second microchannel 110b, the third microchannel 110c simultaneously). The refrigerant may then circulate through the first microchannel 110a, the second microchannel 110b, the third microchannel 110c in the clockwise direction, and may then enter the second header 108b. The refrigerant may move down in the second header 108b and then enter another set of microchannels, circulate in a counterclockwise direction and then enter the first header 108a, thereby enabling refrigerant circulation through the plurality of microchannels 110. ( 035 FIG. 2 depicts a top view of the water heater 100 in accordance with one or more embodiments of the present disclosure. Specifically, FIG. 2 depicts top views of the first header 108a, the second header 108b, and the first microchannel 110a that may be wrapped around the water storage tank 102 and the first header 108a and the second header 108b.(0036] In some aspects, the first microchannel 110a (and other microchannels of the plurality of microchannels 110) may be wrapped around the second header 108b from a second header back surface 202, as shown in view 204. The header back surface 202 is a surface that faces the water storage tank 102. In this manner, the first microchannel 110a may be disposed between the water tank 102 and the second header 108b such that the first microchannel 110a at least partially wraps around the second header 108b between the water tank 102 and the second header 108b. That is, the first microchannel 110a may attached to the second header 108b on a side of the second header 108b closest to the first header 108a. The first microchannel 110a may then at least partially wrap around the second header 108b and pass between the water tank 102 and the second header 108b and extend around the water storage tank 102 until the first microchannel 110a attaches to the first header 108a. Similarly, the first microchannel 110a may be wrapped around the first header 108a in a similar manner and connected to the first header 108a on a side of the firstheader 108a closest to the second header 108b. For example, the first microchannel 110a from a first header back surface, and the first microchannel 110a may be disposed between the water tank 102 and the first header 108a such that the first microchannel 110a at least partially wraps around the first header 108a between the water tank 102 and the first header 108a and connects to the first header 108a on a side of the first header 108a closest to the second header 108b.|0037] In an exemplary aspect, the first microchannel 110a may have a curved portion at a microchannel first end 206 that may be inserted in the second header 108b. The curved portion may enable wrapping of the first microchannel 110a around the second header 108b. Similarly, the first microchannel 110a may have a curved portion at another end (e.g., a microchannel second end, not shown) that may be wrapped around the first header 108a. In the exemplary aspect shown in FIG. 2, the microchannel first end 206 may be a U- shaped and / or J-shaped end that may enable the first microchannel 110a to conveniently wrap around second header back surface 202 between the water tank 102 and the second header 108b.[00381 In additional aspects, the first microchannel 110a may be connected to the second header 108b from a second header side surface 208 that may be disposed on a side of the second header 108b closest to the first header 108a (and may be in proximity to a second header front surface opposite to the second header back surface 202). Stated another way, the first microchannel 110a may be wrapped around the second header back surface 202 and may be attached / inserted to the second header 108b from the second header side surface 208. In some aspects, the second header 108b may include a recess / cavity (or a depression) at the second header side surface 208 that may be disposed throughout a second header length, which may enable second header 108b to conveniently receive multiple microchannels (including the first microchannel 1 10a and other microchannels of the plurality of microchannels 110). Specifically, the recess / cavity may be configured to receive end portion of each microchannel of the plurality of microchannels 110. The recess / cavity (or a depression) at the second header side surface 208 may be disposed on a side of the second header 108b closest to the first header 108a. In some aspects, the second header 108b may have a pie-shaped cross section (e.g., a circular cross-section having a triangular-shaped or V-shaped cut out) that may enable the second header 108b to receive the plurality' of microchannels 110. Similarly, the first header 108a may have a pie-shapedcross section similar to the one described above with reference to the second header 108b to receive the plurality of microchannels 110. For example, the recess / cavity (or a depression) in the first header 108a may be disposed on a side of the first header 108a closest to the second header 108b.|O039] In further aspects, the second header 108b may have a slot (shown as slots 306 in FIG. 3) into which the first microchannel 110a may be inserted and may be attached / locked using a fastening mechanism. Specifically, the second header 108b may include a plurality of slots disposed throughout the second header length that may enable the second header 108b to receive the plurality of microchannels 110.[0040 The first microchannel 110a may be wrapped from the second header back surface 202 to increase the surface area (i.e., the surface area of the first microchannel 110a against the exterior surface of the water storage tank 102) such that the gap between the first microchannel 110a and the water storage tank 102 (which may exist due to connection between the first microchannel 110a and the second header 108b) may be reduced. By reducing the gap, the present disclosure considerably reduces probability of accumulation of insulating material (e.g., polyurethane foam) between the surfaces of the first microchannel 110a and the water storage tank 102, thereby enhancing water heater performance. In some aspects, the second header 108b (and the first header 108a) may not be in contact with the water storage tank exterior surface, and the first microchannel 110a may be disposed between the second header 108b (e.g., second header back surface 202) and the water storage tank exterior surface.(0041] Although FIG. 2 depicts connection between the first microchannel 110a and the second header 108b, it may be appreciated that the first microchannel 110a may be similarly connected with the first header 108a. In addition, other and / or all microchannels of the plurality of microchannels 110 may be similarly wrapped around the first header 108a and / or the second header 108b.10042 ] FIG. 3 depicts an interaction of one or more microchannels in a header 300 in accordance with one or more embodiments of the present disclosure. Specifically , FIG. 3 depicts interaction of microchannels 302 and 304 in the header 300. The header 300 may be same as the first header 108a and / or the second header 108b, and the microchannels 302 and 304 may be part of the plurality of microchannels 110.As described above in conjunction with FIG. 2, the header 300 may include slots (such as the slot 306) to receive the microchannels 302 and 304. The slots 306 may be through-holes into which respective ends associated with the microchannels 302 and 304 may be inserted. The slot size may be equivalent to microchannel thickness.| f>44J In some aspects, the microchannels 302 and 304 may be disposed at a predetermined distance from each other and may be configured to facilitate circulation of refrigerant around a water storage tank length. Specifically, the refrigerant may flow through the microchannel 302 in the exemplary direction depicted in FIG. 3 and may enter the header 300 via first slot (or opening) at a microchannel outlet end 308. When the refrigerant enters the header 300, a microchannel inlet end 310 of an adjacent microchannel may receive the refrigerant from the header 300 and may enable refrigerant circulation in the indicated direction. In this manner, the microchannel 304 may receive the refrigerant from the microchannel 302 via the header 300. Stated another way, the microchannels 302 and 304 “interact” with each other via the header 300 or inside the header 300 such that the refrigerant is directed into adjacent microchannels.[0 45 In some aspects, both the outlet end 308 and the inlet end 310 may be tapered ends (hereinafter referred to as tapered end 308 and tapered end 310, respectively). Stated another way, in some aspects, width of each of the outlet end 308 and the inlet end 310 may be less than widths of the microchannels 302 and 304, respectively. The tapered end 308 and the tapered end 310 may be positioned such that the microchannel 302 may efficiently transfer the refrigerant to the microchannel 304. Stated another way, the tapered end 308 and the tapered end 310 may be positioned such that the tapered end 308 and the tapered end 310 may be at a predetermined angle relative to each other to effectively transfer the refrigerant from the microchannel 302 to the microchannel 304, as depicted in FIG. 3. For example, the tapers may face one another within the header 300 so that refrigerant generally flows from one microchannel to the next via the header 300, thereby enabling circulation of the refrigerant in the heat exchanger 104.

[0046] In some aspects, the header 300 may be cylindrical in shape, as depicted in view 312. Specifically, the view 312 indicates a top view of the header 300. The view 312 depicts an exemplary view of the microchannels 302, 304 at least partially wrapped around the header 300, as described above in conjunction with FIG. 2.j0047] FIG. 4 depicts an isometric view of another embodiment of a water heater 400 in accordance with one or more embodiments of the present disclosure. The water heater 400 may be similar to the water heater 100. As described above in conjunction with FIG. 1, the water heater 400 may include the water storage tank 102 and the heat exchanger 104 that may be at least partially wrapped around the water storage tank 102 and may be configured to transfer heat from a fluid (e.g., the refrigerant) to the water stored in the water storage tank 102. The heat exchanger 104 may include the first header 108a, the second header 108b, and the plurality of microchannels 1 10, as described above in conjunction with FIG. 1. 0O48| In some instances, the plurality of microchannels 110 may be grouped in bands. The plurality of microchannels 110 may be disposed such that a predetermined spacing exists between adjacent bands of microchannels. In some aspects, the predetermined spacing may be the same between each adjacent microchannel bands. In other aspects, the predetermined spacing may be different. For example, a predetermined spacing between microchannel bands may be larger than a predetermined spacing between other microchannel bands. In the exemplary aspect depicted in FIG. 4, the first microchannel band 110a, the second microchannel band 1 10b, and the third microchannel band 110c may be disposed at a first predetermined distance “DI” from adjacent microchannel bands. Further, the third microchannel band 110c may be disposed at a second predetermined distance “D2” from the fourth microchannel band 1 lOd. In some instances. D2 may be in a range of about 125mm to 155mm. D2 may be any suitable distance and not limited to the provided range of D2. In some instances, the second predetermined distance “D2” may be greater than the first predetermined distance “DI” so that the third microchannel band 110c and the fourth microchannel band 1 lOd may not contact or interfere with other water heater parts that may be disposed on water storage tank exterior surface, e.g., couplings 402, as shown in FIG. 4. Remaining microchannel bands may again be disposed at the first predetermined distance “DI” from the adjacent microchannel bands, as depicted in FIG. 4.The second predetermined distance “D2” between the microchannel bands (such as the third microchannel band 110c and the fourth microchannel band 1 lOd) may further facilitate the plurality of microchannel bands 110 to cover more surface area around the water storage tank 102, thereby increasing waler heater efficiency.

[0050] FIG. 5 depicts a flow diagram of an example method to dispose a plurality of microchannels in a water heater in accordance with one or more embodiments of the present disclosure. FIG. 5 may be described with continued reference to prior figures, including FIGS. 1-4. The following process is exemplary and not confined to the steps described hereafter. Moreover, alternative embodiments may include more or less steps that are shown or described herein and may include these steps in a different order than the order described in the following example embodiments. 0051] The method 500 may start at step 502. At step 504, the method 500 may include positioning the plurality of microchannels 110 around the water storage tank 102. At step 506, the method 500 may include at least partially wrapping the plurality of microchannels 110 around the first header 108a and the second header 108b, as described above in conjunction with FIGS. 1-3. The method 500 stops at step 508.

[0052] FIG. 6 depicts example stages of manufacturing a microchannel in accordance with one or more embodiments of the present disclosure. Specifically, FIG. 6 depicts three stages (e.g., a stage 602, a stage 604 and a stage 606) of manufacturing a microchannel using a folding method / process. At the stage 602, a plurality of ridges 608 may be formed on two side edges (e.g., a first portion 610 and a second portion 612) of an aluminum sheet (e.g., single sheet) or any other metal sheet, and folded on a third portion 614 and a fourth portion 616 of the single sheet. The third portion 614 may be adjacent to the first portion 610 and the fourth portion 616 may be adjacent to the second portion 612. In some aspects, the first portion 610 may be folded about an intersection point of the first portion 610 and the third portion 614, and the second portion 612 may be folded about an intersection point of the second portion 612 and the fourth portion 616.[00531 A length of the first portion 610 may be equivalent to a length of the third portion 614, and a length of the second portion 612 may be equivalent to a length of the fourth portion 616. A center portion (e.g., a fifth portion 618) may exist between the third portion 614 and the fourth portion 616 that may not include the plurality of ridges 608, as shown in FIG. 6. In some aspects, a length of the fifth portion 618 may be equivalent to a sum of the lengths of the third portion 614 and the fourth portion 616. The plurality of ridges 608 may be of any size and shape. For example, the plurality of ridges 608 may be trapezoidal or frustoconical in shape.[0 5 At the stage 604, the third portion 14 and the fourth portion 616 may be folded towards each other. For example, at the stage 604, the third portion 614 and the fourth portion 616 may be folded to be perpendicular to the fifth portion 618, as shown in FIG. 6. Stated another way, the third portion 614 and the fourth portion 616 may be made to be parallel to each other and perpendicular to the fifth portion 618. In some aspects, the third portion 614 may be folded about an intersection point of the third portion 614 and the fifth portion 618, and the fourth portion 616 may be folded about an intersection point of the fourth portion 616 and the fifth portion 618. 0055^ At the stage 606, the third portion 614 and the fourth portion 616 may be folded to overlay on the fifth portion 618. At this stage, the plurality of ridges 608 of the third portion 614 and the fourth portion 616 may contact the fifth portion 618. The third portion 614 and the fourth portion 616 may be sealed together (e.g., welded) to form the microchannel shown in FIG. 6.

[6056] In the above disclosure, reference has been made to the accompanying drawings, which form a part hereof, which illustrate specific implementations in which the present disclosure may be practiced. It is understood that other implementations may be utilized, and structural changes may be made without departing from the scope of the present disclosure. References in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a feature, structure, or characteristic is described in connection with an embodiment, one skilled in the art will recognize such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.|<MJ57] It should also be understood that the word “example” as used herein is intended to be non-exclusionary and non-limiting in nature. More particularly, the word “example” as used herein indicates one among several examples, and it should be understood that no undue emphasis or preference is being directed to the particular example being described. 0058^ With regard to the processes, systems, methods, heuristics, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practicedwith the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of processes herein are provided for the purpose of illustrating various embodiments and should in no way be construed so as to limit the claims.

[6059] Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent upon reading the above description. The scope should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the technologies discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the application is capable of modification and variation.

[0060] All terms used in the claims are intended to be given their ordinary meanings as understood by those knowledgeable in the technologies described herein unless an explicit indication to the contrary' is made herein. In particular, use of the singular articles such as “a,” "the." “said,” etc., should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments could include, while other embodiments may not include, certain features, elements, and / or steps. Thus, such conditional language is not generally intended to imply that features, elements, and / or steps are in any way required for one or more embodiments.

Claims

CLAIMSTHAT WHICH IS CLAIMED IS:

1. A water heater comprising: a water tank configured to store water; and a heat exchanger disposed about the water tank, wherein the heat exchanger comprises: a first header; and a plurality of microchannels attached to the first header, wherein the plurality of microchannels is at least partially wrapped around the water tank, wherein the plurality of microchannels is configured to circulate a heat transfer fluid therein via the first header to transfer heat to the water, and wherein each microchannel is at least partially wrapped around the first header between the first header and the water tank.

2. The water heater of claim 1, wherein each microchannel comprises a curved portion at an end position to enable wrapping of the microchannel around the first header.

3. The water heater of claim 1, wherein the first header is an elongated tube, and wherein the first header comprises a plurality of slots to receive respective microchannels.

4. The water heater of claim 1, wherein the first header comprises a recess along a first header length to receive end portion of each microchannel.

5. The water heater of claim 1, wherein each microchannel is disposed at a predetermined distance from adjacent microchannels.

6. The water heater of claim 1, wherein each microchannel comprises a tapered end to enable circulation of the heat transfer fluid in the heat exchanger.

7. The water heater of claim 1, wherein each microchannel is disposed between the first header back surface and the water tank.

8. The water heater of claim 1 further comprising a second header attached to the plurality of microchannels.

9. The water heater of claim 8, wherein the first header and the second header are disposed at a predetermined distance from each other.

10. A water heater comprising: a water tank configured to store water; a heat exchanger at least partially wrapped around the water tank, wherein the heat exchanger comprises: a first header; and a plurality of microchannels attached to the first header, wherein each microchannel is at least partially wrapped around the first header between the first header and the water tank, and wherein each microchannel comprises a curved portion at an end position to enable w rapping of the microchannel around the first header.

11. The w ater heater of claim 10, wherein the first header is an elongated tube, and wherein the first header comprises a plurality of slots to receive respective microchannels.

12. The water heater of claim 10, wherein the first header comprises a recess along a first header length to receive end portion of each microchannel.

13. The water heater of claim 10, wherein each microchannel is disposed at a predetermined distance from adjacent microchannels.

14. The w ater heater of claim 10, wherein each microchannel comprises a tapered end to enable circulation of the heat transfer fluid in the heat exchanger.

15. The w ater heater of claim 10, w herein each microchannel is disposed between the first header back surface and the w ater tank.

16. The water heater of claim 10 further comprising a second header attached to the plurality of microchannels.

17. The water heater of claim 16, wherein the first header and the second header are disposed at a predetermined distance from each other.

18. A method of assembling a heat exchanger to a water tank of a water heater, the method comprising: positioning a first header about the water tank; positioning a plurality of microchannels around the water tank; at least partially wrapping the plurality of microchannels around first header between the first header and the water tank; and attaching the plurality' of microchannels to the first header.

19. The method of claim 18. further comprising; positioning a second header about the water tank; at least partially yvrapping the plurality of microchannels around second header between the second header and the water tank; and attaching the plurality of microchannels to the second header.

20. The method of claim 18, tapering ends of the plurality' of microchannels within the first header and / or the second header.

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