Patent Publication Number: US-2017356674-A1

Title: Water management header for a boiler or water heater

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and benefit of U.S. Provisional Patent Application No. 62/349,278, filed Jun. 13, 2016, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Heat exchangers are devices for transferring heat from one medium to another, typically from one fluid to another or to a surrounding environment, without allowing the fluids to mix. Some examples are: automobile radiators; air conditioners, and steam hot water radiators, and water boilers and heating systems, which are used to produce or remove heat. 
     Commercial and residential water heaters typically heat water by generating tens of thousands, and even hundreds of thousands, of British Thermal Units (“BTUs”). The performance of a water heater may be considered in terms of the efficiency of the water heater, that is, the effectiveness of the water heater in transferring heat to an associated fluid flow. Various factors, such as the physical configuration of the water heater and/or the physical configuration of other components in a water heater system, for example, may impart undesirable characteristics to the fluid flow that can, in turn, adversely affect the performance of the fluid heater. For example, the number of times a fluid passes a heat source and/or the load of the water heater, i.e., the amount of temperature change necessary, directly affects the efficiency of a water heater. 
     Various heat exchangers are used for different applications. A different heat exchanger might be used for an application requiring a large temperature change between a cold fluid inlet and a warm fluid outlet as opposed to an application requiring a smaller temperature change. 
     SUMMARY OF THE INVENTION 
     To improve heat exchanger efficiency and versatility as well as provide other benefits, disclosed is an inventive water management header that can be used with a heat exchanger such as a boiler or water heater. The water management header includes a shell that at least partially defines an interior region. 
     An inner series of heat exchange tubes and an outer series of heat exchange tubes extends within the interior region of the shell from a lower end of the shell to an upper end of the shell. The water management header is positioned in the upper and/or lower end of the shell and receives water from the heat exchange tubes within the shell. The shell is generally cylindrical. 
     The header includes a cover and an interior region. A plurality of crossovers may be within the interior region of the cover and in fluid flow communication with the outer series of heat exchange tubes. A waterway primary outlet is within the interior of the cover and in fluid flow communication with the inner series of heat exchange tubes. A retainer is also within the interior of the cover and divides the interior of the cover into an undivided waterway and a divided crossover area. 
     The present apparatus is capable of providing a unique fluid flow throughout the inner series of heat exchange tube and/or the outer series of heat exchange tubes. The plurality of crossovers along with the waterway primary outlet may customize the fluid flow via various placements and a plurality of supports alternately positioned between a plurality of through holes and a plurality of barriers. 
     A method of manufacturing a boiler or water heater includes positioning a waterway primary inlet such that inlet openings of the waterway primary inlet are aligned to receive water from the heat exchange tubes. The method also includes selecting from among the inlet openings of the waterway primary inlet a set of inlet openings to be in flow communication with one another. Barriers are positioned in the waterway primary inlet such that they are retained by supports of the waterway primary inlet, permit flow between the set of inlet openings, and restrict flow between the set of inlet openings and other inlet openings of the waterway primary inlet. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an exploded view of the inventive water management header in accordance with aspects of the present invention; 
         FIG. 2A  shows a top water management header attached to a water heater shell according to aspects of the present invention; 
         FIG. 2B  shows a bottom water management header attached to a water heater shell in accordance with aspects of the present invention; 
         FIGS. 3A-3D  show a cross over component of the water management header of  FIG. 1 ; 
         FIGS. 4A-4E  show elevation, perspective, top, and cross-sectional views, respectively, of a waterway primary outlet of the water management header of  FIG. 1 ; 
         FIG. 4F  shows a barrier support that is within the waterway primary outlet of  FIG. 4A ; 
         FIGS. 5A-5C  show perspective, top, and cross-sectional views, respectively, of a top cover of the water management header of  FIG. 1 ; 
         FIGS. 6A-6C  show perspective, front, and side views, respectively, of a barrier of the water management header of  FIG. 1 ; 
         FIGS. 7A-7C  show perspective, top, and cross-sectional views of a seal of the water management header of  FIG. 1 ; 
         FIGS. 8A-8   c  show perspective, top, and cross-sectional views, respectively, of a bottom cover of the water management header of  FIG. 1 ; 
         FIGS. 9A and 9B  show perspective and top views, respectively, of a waterway primary inlet of the water management header of  FIG. 1 ; 
         FIG. 9C  shows a barrier support that is within the waterway primary inlet of  FIG. 8A ; 
         FIG. 9D  shows a cross-sectional view of the waterway primary inlet of  FIG. 8A ; 
         FIG. 10  shows a further embodiment of a water management header according to aspects of the present invention; 
         FIGS. 11A-11C  show a perspective top-side view as well as a perspective and elevated bottom-side view of an inverted water primary outlet of  FIG. 10 ; 
         FIGS. 12A-13B  illustrate additional embodiments of an inverted top manifold and an inverted bottom manifold in accordance with aspects of the present invention; 
         FIG. 14A  illustrates an additional embodiment of a water management header having a water primary inlet connected directly to a tube sheet according to aspects of the invention; 
         FIG. 14B  illustrates a cross-sectional view of the embodiment of  FIG. 14A ; and 
         FIG. 15  illustrates another embodiment of a water management header having a gasket positioned between a water primary outlet and tube sheet in accordance with aspects of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Disclosed is an inventive water management header that can be attached to a heat exchanger, such as a boiler or water heater  2 , as shown in  FIGS. 1, 2A, and 2B . The water heater or boiler  2  further has a water inlet  22  and a water outlet  24 . Desirably, a top header  50  is positioned at an upper end of the shell  4  and/or a bottom header  52  is at the bottom end of the shell  4 . Each of the headers  50  and  52  contains the water management header  10  for providing the unique fluid flow between the heat exchange tubes. This includes a waterway crossover section  20 , a waterway  18  and a retainer  16 . The retainer  16  is a barrier separating the waterway crossover section  20  from the waterway  18 . 
     The water management header  10  includes a shell  4  that at least partially defines an interior region  48 . The shell  4  may have a generally cylindrical shape. The shape of the shell  4  is not limited to any particular geometrical shape. An inner series of heat exchange tubes  6  and an outer series of heat exchange tubes  8  extends within the interior region  48  of the shell  4  from a lower end of the shell  4  to an upper end of the shell  4 . 
     The water management header  10  is positioned in the upper end of the shell  4  and receives water from the outer series of heat exchange tubes  8 . The water management header  10  includes a cover  12  and an undivided waterway  18 . A retainer  16  is within the interior of the cover  12  and divides the interior of the cover  12  into the undivided waterway  18  and a divided crossover section  20 . A plurality of crossovers  14  are within the crossover section  20  of the cover  12  and in fluid flow communication with the outer series of heat exchange tubes  8 , a waterway primary outlet  26  within the interior of the cover  12  and in fluid flow communication with the inner series of heat exchange tubes  6 . A gasket  17  is provided between the retainer  16  and the waterway primary outlet  26 . 
     The lower header  52  includes a lower cover  44  (shown in  FIGS. 8A-8C ) and has an inlet through hole  46  and a half-toroidal shape. A waterway primary inlet  38  has a plurality of waterway primary inlet through holes  40 . While the cover  12  has a through hole  32 , there is no such through hole in the lower cover  44  as it is not necessary in this embodiment. However, should an upward fired blower be used in the disclosed embodiments, a cover with a through hole should be provided to allow for the addition of a combustion device. 
     The cover  12  and the waterway primary outlet  26  are separate components. The cover  12  may be drawn from a metallic sheet. Also, the cover  12  and the crossovers  14  are separate components. The geometry of the crossovers  14  is shown in  FIGS. 3A-3C . Each crossover  14  is rounded and is sized to encompass an outlet and an inlet of the outer series of tubes  8 . Although each crossover  14  is rounded in  FIGS. 1-3, and 10 , the crossovers  14  may form any geometric shape that enables the crossovers  14  to direct fluid flow from one tube to another tube, e.g., between the outer series of tubes  8 . The inlet (or plurality of inlets, as discussed in more detail below) provides water to the crossover  14  at a crossover inlet  15 , and water exits the crossover  14  at a crossover outlet  19 . The crossovers  14  may have projections  68  that facilitate a water tight seal with the gasket  17  or  66 . 
     Each crossover  14  is preferably molded from polymeric material. Other materials including various metals, such as copper and aluminum are also possible. The crossovers  14  and retainer  16  may also be separate components. Together, the crossovers  14  and the retainer  16  contain water and direct water flow between the inner series of tubes  6  and the outer series of tubes  8 . 
     The inner series of tubes  6  and the outer series of tubes  8  selectively connect to any of the crossovers  14  to provide for a selective and unique water flow pattern between the water inlet  22  and water outlet  24  throughout the series of tubes  6 ,  8 . As such, the fluid flow path between any of the tubes is determined, in part, by how the crossovers  14  are configured. Each crossover  14  connects at least two of the ends of the series of heat exchange tubes  6 ,  8 . Longer crossovers  14  can be used to connect three or more tubes or tubes that are in close proximity to each other but not necessarily neighboring each other. 
     The fluid flow path, along with the fluid flow characteristics, may also be adjusted by way of various configurations in the waterway primary outlet  26  and/or waterway primary inlet  38 . The waterway primary outlet  26  directs the fluid flow from one tube to another tube, e.g., of the inner series of heat exchanger tubes  6 . In one embodiment, illustrated in  FIGS. 1 and 4 , the water primary outlet  26  defines water inlet openings  40 . The water inlet openings  40  are positioned to receive water, such as by aligning with the openings of the inner series of tubes  6 . The water primary outlet  26  may not include water inlet openings  40 , e.g., as later described with regard to an inverted water primary outlet  62  and/or  262 . 
     As shown in  FIGS. 9A-9D , the waterway primary inlet  38  is configured similar to that of the waterway primary outlet  26 . However, there is no need to connect the waterway primary inlet  38  to a water heater outlet (or inlet) as with the waterway primary outlet  26 . Hence, there is no need for a waterway outlet  43 . The waterway primary outlet  26  is juxtaposed between the inner series  6  of tubes and the retainer  16 . The retainer  16  is perforated to allow fluid flow between the retainer  16  and the waterway  18 . The waterway primary outlet  26  receives fluid from a first tube of the inner series of tubes  6  and supplies fluid to a second tube of the inner series of tubes  6 . 
     With reference to  FIGS. 4A-4F  and  FIGS. 9A-9D , barriers  36  are retained by supports  34 , e.g., between the water inlet openings  40 . The barriers  36  divide the area within the waterway primary outlet  26  or waterway primary inlet  38  into redirecting compartments  35  and/or a crossover area within the waterway primary outlet  26 . The supports  34  are essentially channels that are within the waterway primary outlet and between each of the water inlet openings  40 . The supports are shaped to receive the barriers  36 . The barriers  36  are like walls that are shaped to extend across the crossover section  20  within the waterway  18 . 
     The barriers  36  can be placed in any of the supports  34  to produce redirecting compartments  35 . As such, fluid flow of a water heater or boiler  2  using aspects of the inventive subject matter may not be limited to one path. During construction of the water heater or boiler, fluid flow is determined based on where barriers  36  are positioned in the waterway primary outlet  26 . The barriers  36  can be positioned in every other support, or they can be positioned in an asymmetrical pattern within the waterway primary outlet  26 . Placement of the barriers  36  is dependent on the requirements of the water heater or boiler and the desired fluid flow path throughout the water heater or boiler. Accordingly, in one embodiment of this invention, the water management header  10  can provide flexibility in the arrangement, reconfiguration, and modification of the fluid flow path. 
     Barriers  36  work in conjunction with the waterway primary outlet  26  and a waterway primary inlet  38  (discussed below) in that water enters the waterway primary outlet  26  from one of the tubes of the inner series of tubes  6  into a redirecting compartment  35  that may be bound by the waterway primary outlet  26  on three sides, barriers  36  on two sides, and a tube sheet  27  on a sixth side. After entering into the redirecting compartment  35 , the direction of the fluid flow is directed into another tube, e.g., of the inner series of tubes  6 , that is fluidly connected to the same redirecting compartment  35 ; or, alternatively, the fluid flow is directed toward the waterway outlet  43  to exit the water heater or boiler  2 . 
     The redirecting compartment  35  in the waterway primary outlet  26  and/or waterway primary inlet  38  can be expanded by removing one of the barriers  36  so that multiple tubes provide fluid to the same redirecting compartment  35  and/or multiple tubes provide an outlet for the same redirecting compartment  35 . Alternatively, the redirecting compartment  35  in the waterway primary outlet  26  can be reduced in size by adding barriers  36 . 
     Any number of variables helps dictate where barriers  36  should be positioned in the waterway primary outlet  26  and/or waterway primary inlet  38  as the number, size, and relative location of the redirecting compartments  35  may be modified based on various positioning of the barriers. For instance, in applications where fluid flow through the boiler or water heater  2  is low, e.g., when the load on the water heater (volumetric flow rate) is low during a given time, fewer passes through the inner and outer heat exchange tubes are necessary to maximize heat transfer to the fluid within the tubes. With fewer passes, fewer barriers  36  are required. The barriers can be spaced out around the waterway primary outlet  26  or, perhaps less preferably, they can be concentrated in one section of the waterway primary outlet  26 . In contrast, in applications where fluid flow through the water heater is high, e.g., when the load on the water heater (volumetric flow rate) is high during a given time, the water heater or boiler  2  can be designed to have additional passes. In such an application, more barriers  36  are required in order to help redirect flow throughout the heat exchange tubes  6  and  8 . A maximum number of passes throughout the heat exchange tubes requires a barrier  36  to be placed in every other support  34  of the waterway primary outlet  26 . 
     The barriers  36  are preferably affixed to the waterway primary outlet  26  in any manner that provides a watertight seal. Suitable means for affixing the barriers  36  to the waterway primary outlet  26  and/or water primary inlet  38  include adhesives, mechanical means, fastening, bolting, screwing, friction, fusing, welding, etc. It is possible that the waterway primary outlet  26  can be used without the supports  34 . In such an instance, the barriers  36  are not limited to the location of the supports  34 . Rather, the barriers  36  are placed anywhere in the waterway primary outlet  26  and/or water primary inlet  38  that is necessary to provide the desired number of passes of the fluid flow through the water heater or boiler  2 . 
     The geometry of an embodiment of the barrier  36  is shown in  FIGS. 6A-6C . The geometry is not limited to that shown, although preferably the barriers  36  help to provide a watertight seal with the waterway primary inlet  38  and/or the waterway primary outlet  26 . The barriers  36  can also be configured in layers. For example, the barriers  36  might include a layer of polyurethane surrounded by layers of a metallic material. With such a sandwiched configuration, the barrier  36  would have a greater coefficient of restitution, which enables the barriers  36  to fit more snuggly in the supports  34 . 
     As shown in  FIGS. 7A-7C , seal  28  connects the water outlet  24  to an exterior volume of the water heater or boiler  2  and seals the water outlet  24  from the interior region  48  of the cover  12 . The retainer  16  comprises at least one through hole  30  for accessing the waterway primary outlet  26 . 
     The cover  12  has a curved cross section that reduces stress imposed on the cover  12  by fluid pressure. As can thus be seen in  FIGS. 5A-5C , one possible configuration of the cover  12  is a half toroid. As such, the cover  12  has a through hole  32  at its center. The through-hole  32  allows combustion gas to enter the water heater. 
     Thus, the present apparatus is a system that provides a unique fluid flow throughout the inner series tubes  6  and/or the outer series of h tubes  8 . The plurality of crossovers  14  along with the waterway primary outlet  26  are customizable via a plurality of supports  34  selectively positioned between a plurality of through holes and a plurality of barriers  36  engaging the plurality of supports  34 . 
     Either or both of the waterway primary outlet  26  or the waterway primary inlet  38  can be inverted from the embodiment discussed above.  FIG. 10  shows a further embodiment of a water management header  74 , which has an inverted waterway primary outlet  62 . As depicted in  FIGS. 11A-11C , the inverted waterway primary outlet  62  has a U-shaped cross section. There is no need for through holes  40  in the inverted waterway primary outlet  62  as the portion of the inverted waterway primary outlet  62  that is in communication with the inner series of tubes  6  is the opening of the U-shaped cross section. The inverted water primary outlet  62  has waterway outlet  143 , which delineates an opening that permits water to exit the water heater or boiler  2 . The inverted water primary outlet  62  may also have a through hole  130 , which facilitates fluid flow into and/or out of the waterway in the inverted water primary outlet  62 . 
     A gasket  66  is provided between the inverted waterway primary outlet  62  and the tube sheet  27 . One of the benefits of employing the inverted waterway primary outlet  62  is ease of manufacturing. The crossovers  14 , and if employed, the projections  68  on the crossovers  14 , and the inverted waterway primary outlet  62  engage the gasket  66 . This provides more stability and enhanced water tightness. 
     A U-shaped rectilinear bracket  70  may be placed over a retainer  72 . Fasteners engage the U-shaped rectilinear bracket  70  to hold the bracket  70 , the retainer  72 , the inverted waterway primary outlet  62 , the gasket  66 , and the tube sheet  27  together in a water management header  74 . Bolts or threaded fasteners may extend from either the tube sheet  27  through water management header  74  toward the U-shaped rectilinear bracket  70  or vice versa to hold the water management header  74  together. In this embodiment, it is not necessary to weld or braze the inverted waterway primary outlet  62  (or waterway primary inlet, if configured similarly) to the tube sheet  27  as sufficient compression to form a water tight seal between active components is provided by the fasteners in the water management header  74 . 
     One or more features described herein may be integrally formed as one unitary component. Employing one component that includes one or more features of embodiments of the present invention enables simpler manufacturing, reduced build times, and is more cost efficient. However, as one or more features that enable variation of the fluid flow are formed of one integral component, the flexibility of the fluid flow (e.g., the ability to modify the fluid flow characteristics such as the number of passes, the velocity of the fluid, etc.) is reduced. Accordingly, aspects of the present invention enable one of skill in the art to advantageously design boilers or water heaters with a balance between the amount of flexibility of the fluid flow and the easy of manufacture. 
     With reference to  FIGS. 12A-12B , an inverted top manifold  210  for the top header  50  may be formed as one component that integrally includes the inverted waterway primary outlet  262 , the barriers  236 , the crossovers  214 , the retainer  272 , and the seal  228 . With reference to  FIGS. 13A-13B , an inverted lower manifold  220  for the lower header  52  may be formed as one component that integrally includes the inverted primary waterway inlet  226 , the barriers  236 , the crossovers  214 , the retainer  272 , the gasket  266 , and the seal  228 . The inverted top manifold  210  and the inverted lower manifold  220  may be employed in the top header  50  and the lower head  52 , respectively. 
     In an embodiment employing the inverted manifolds  210  and  220 , depicted in  FIGS. 12-13 , fluid (e.g., water) enters the lower header  52  of the water heater or boiler  2  by flowing through the fluid inlet  22 , through inlet through hole  46 , and into a region encapsulated by the lower cover  44 , e.g., the undivided waterway of the lower header  52 . The fluid may be in contact with the top surface  222  of the lower inverted manifold  220  while in the region encapsulated by the lower cover  44 . The gasket  66  may be molded to fit directly under the inverted top manifold  210  and/or the inverted lower manifold  220  to seal the fluid within the top cover  12  and/or the lower cover  44 . Subsequently, the fluid flows into one or more of the outer series of tubes  8  that are in fluid communication with the region encapsulated by the lower cover  44  of the lower head  52 . 
     After passing through one or more of the determined outer series of tubes  8 , the fluid may enter the crossover portion  214  of the upper inverted manifold  210 . The crossover portion  214  of the inverted top manifold  210  preferably redirects the water into another tube of the outer series of tubes  8 , but may in some embodiments redirect the water into one or more of the inner series of tubes  6 . The number of additional passes through the outer series of tubes  8  depends on various factors described herein such as, e.g., the number of crossovers  214 , the number of outer tubes  8 , and the volumetric flow rate of the fluid. For example, the crossover portions  214  of the inverted top manifold  210  and the inverted lower manifold  220  may redirect water through the outer series of tubes  8  to produce a double pass, triple pass, quadruple pass, etc. 
     In accordance with the embodiment depicted in  FIGS. 12-13 , the fluid exits the outer series of tubes  8  and enters into a region encapsulated by the cover  12 , e.g., the undivided waterway  18  of the top header  50 . While in the region encapsulated by cover  12 , the fluid may be in contact with the top surface  212  of the inverted top manifold  210 . The region encapsulated by the cover  12  is in fluid communication with through hole  230 , which enables the fluid to enter the inverted water primary outlet portion  262  of the inverted top manifold  210 . 
     The fluid is subsequently directed into one or more of the inner series of tubes  6  by way of redirecting compartments  235  of the inverted top manifold  210 , thereby making a first pass through one or more of the determined inner series of tubes  6 . After making a first pass through the one or more determined inner series of tubes  6 , the fluid flows into the redirecting components  235  of the inverted water primary inlet portion  226  of the inverted lower manifold  220 . The fluid may be redirected between the redirecting components  235  of the inverted top manifold  210  and the inverted lower manifold  220  numerous times depending the various factors described herein, e.g., the number of redirecting components  235 , the number of inner tubes  6 , and volumetric flow rate of the fluid. For example, the fluid may be redirected through the inner series of tubes  6  to produce a double pass, triple pass, quadruple pass, etc. Although the barriers  236  are depicted as integrally formed with the inverted manifolds  210  and/or  220 , the barriers  236  may be affixed at various portions, e.g., by way of the supports  34 , of the inverted manifolds  210  and/or  220 . 
     After the fluid flows through the determined number of passes, the fluid enters the redirecting compartments  235  containing the waterway outlet  243 , which is in fluid communication with the water outlet  24 . The redirecting compartment  235  that redirects the fluid to the water outlet  24  may be larger than other redirecting compartments  235 . 
       FIGS. 14A-15  illustrate two embodiments of a water management header  140  and  150  in accordance with aspects of the present invention. Water management headers  140  and  150  are similar to water management headers  50 ,  52 , and  74 , but includes the differences disclosed herein. Accordingly, where water management headers  140  and  150  utilizes features similar to water management headers  50 ,  52 , and  74 , the same reference numbers are applied. 
     As a general overview, water management header  140  includes water primary inlet  38 , barriers  36 , and a tube sheet  27 . Although  FIG. 14A  illustrates a water management header  140  having a water primary inlet  38 , water management header  140  may in other embodiments be configured to have a water primary outlet  62 . Water primary inlet  38  may be configured such that only edge portion  39  contacts and/or are connected to tube sheet  27 . For example, edge portion  39  of water primary inlet  38  may be directly welded to tube sheet  27 . Alternatively, primary inlet  38  may be directly adhered at edge portion  39  by way of an adhesive to tube sheet  27 . In one embodiment, water primary inlet  38  may be connected to tube sheet  27  without the use of mechanical fasteners, such as bolts, screws, threads, etc. By directly connecting edge portions  39  of primary inlet  38  to tube sheet  27 , water management header  140  may be configured without a gasket (e.g., an o-ring) positioned between the connecting inlet  38  and the tube sheet  27 . 
       FIG. 15  illustrates another embodiment of a water management header  150 . As a general overview, water management header  150  includes water primary outlet  62 , barriers  36 , gaskets  66 A and  66 B, and tube sheet  27 . A method of manufacturing a boiler or water heater includes positioning a waterway primary inlet such that the inlet openings of the waterway primary inlet are aligned to receive water from the heat exchange tubes and supports of the waterway are located proximal to the water inlet openings. The method also includes selecting from among the inlet openings of the waterway primary inlet a set of inlet openings to be in flow communication with one another and positioning barriers in the waterway primary inlet such that they are retained by supports of the waterway primary inlet, permit flow between the set of inlet openings, and restrict flow between the set of inlet openings and other inlet openings of the waterway primary inlet. 
     Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. Numerous variations, changes and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the spirit and scope of the invention.