This application relates generally to water heaters, and more particularly to water heaters having single piece combustion product diverters.
Typical fuel-fired water heaters use fuels, such as natural gas, propane or oil, to heat water contained in a water tank of such water heaters. With such water heaters, a heat exchanger associated with the tank is typically used to heat the water. In some water heaters, hot gas passes through a heat exchanger once to heat the water. In other water heaters, the heat exchanger may include multiple branches, and the hot gas passes through the heat exchanger multiple times to heat the water. The multiple-branched heat exchanger can result in improved thermal efficiency. However, the arrangement of the multiple branches of the heat exchanger in the tank can present challenges to providing a top water outlet without degrading thermal efficiency of the water heater. In some cases, water heaters with a top water outlet may be preferable. Thus, a solution that allows for the construction of a water heater with a top water outlet and using a multiple-pass heat exchanger may be desirable.
A water heater is described in U.S. Pat. No. 10,801,748, the entire disclosure of which is incorporated herein by reference. This will be described in greater detail with reference to
During operation of the water heater 100, unheated water enters the water tank 102 through the water inlet 112, and gas is heated by the combustion system 108. The unheated water gets heated inside the water tank by hot gas flowing through the multi-pass heat exchanger. The resulting heated water exits the water tank 102 through the top water outlet 110 in the top cover assembly 104. The hot gas that flows through the multi-pass heat exchanger may exit the water tank through a hot gas outlet in the bottom assembly 106.
The water heater 100 provides a top water outlet location along with the high efficiency of a multi-pass heat exchanger. By providing the top water outlet 110, the water heater 100 provides a fuel-fired water heater with a top water outlet location that is preferable in some installations.
The second-pass flue tubes 204, 206, 208, and 210 extend out radially from the first-pass flue tube 202 and curve/turn generally upward toward the top opening of the water tank 102. The second-pass flue tubes 204-206 are attached to the first-pass flue tube 202 forming a hot gas flow path from the first-pass flue tube 202 to the second-pass flue tubes 204-206. The hot gas in the first-pass flue tube 202 is provided by the combustion system 108, which can be a down-fired system, as more clearly illustrated in
The second-pass flue tubes 204-210 are substantially parallel to the first-pass flue tube 202 after curving/turning upward. The second-pass flue tubes 204-210 may branch out from the first-pass flue tube 202 proximal to a bottom end of the water tank 102 and may extend upward for a substantial portion of the height of the water tank 102. In some embodiments, the second-pass flue tubes 204-210 may have curves or other variations in extending upward toward the top opening of the water tank 102. Top ends of the second-pass flue tubes 204-210 are terminated in top flues in the top cover assembly 104 of the water heater 100 or may otherwise be in fluid communication with the top flues in the top cover assembly 104 of the water heater 100. For example, the second-pass flue tubes 204, 206 are terminated in a first kidney-shaped top plenum 302, and the second-pass flue tubes 208, 210 are terminated in a second kidney-shaped top plenum 304.
The diverter 406 and the tank cover plate 402 may define the first kidney-shaped top plenum 302, and the diverter 408 and the tank cover plate 402 may define the second kidney-shaped top plenum 304. The gaskets 412, 414 may provide a more reliable seal of the kidney-shaped top plenums 302, 304. The tank cover plate 402 may include holes matching the arrangement of the flue tubes of the heat exchanger 230. The combustion system 108 may include a pipe 410 that is inserted into the first-pass flue tube 202 of the heat exchanger 230. The blower of the combustion system 108 may flow air into the first-pass flue tube 202 through the pipe 410.
The third-pass flue tubes 212-226 may extend in the cavity of the water tank 102 from the top end of the water tank 102 to a bottom end of the water tank 102. Top end openings of the third-pass flue tubes 212-226 are terminated or may otherwise be in fluid communication with the kidney-shaped top plenums 302, 304 in the top cover assembly 104. Hot gas from the second-pass flue tubes 204-210 flows to the third-pass flue tubes 212-226 through the top plenums 302, 304 in the top cover assembly 104. For example, the top end openings of the third-pass flue tubes 212-218 are terminated in the first kidney-shaped top plenum 302 to receive hot gas from the second-pass flue tubes 204, 206, and the top end openings of the third-pass flue tubes 220-226 are terminated in the second kidney-shaped top plenum 304 to receive hot gas from the second-pass flue tubes 208, 210.
The bottom end openings of the third-pass flue tubes 212-226 are terminated in the bottom assembly 106 through openings in a top cover 228 of the bottom assembly 106. For example, the bottom assembly 106 may include a bottom flue 306, and hot gas flowing through the third-pass flue tubes 212-226 may flow to the bottom flue 306 and exit the bottom assembly 106 through a hot gas outlet 310 of the bottom assembly 106.
In operation, as shown in
The somewhat-cooled hot air from the first-pass flue tube 202 is then passed upward through the second-pass flue tubes 204, 206, 208, and 210, each of which additionally heats the water surrounding the respective second-pass flue tubes 204, 206, 208, and 210. Again, by heating the water surrounding the second-pass flue tubes 204, 206, 208, and 210, the somewhat-cooled hot air is then further cooled.
The further cooled hot air from the second-pass flue tubes 204 and 206 is diverted by the first kidney-shaped top plenum 302 and into the third-pass flue tubes 212, 214, 216, and 230. The further cooled hot air from the second-pass flue tubes 208 and 210 is diverted by the second kidney-shaped top plenum 304 and into the third-pass flue tubes 220, 222, 224, and 226.
The further-cooled hot air from the second-pass flue tubes 204, 206, 208, and 210, is then passed downward toward the bottom of the water heater 100 through the third-pass flue tubes 212-226, each of which additionally heats the water surrounding the respective the third-pass flue tubes 212-226. Again, by heating the water surrounding the third-pass flue tubes 212-226, the further-cooled hot air is then still further cooled.
Accordingly, a portion of water in the water heater 100 that is surrounding the flue tubes is heated by conduction via the multiple passes of the hot air through the multiple flue tubes. The remainder of the water in the water heater 100 is heated via a combination of conduction with the heated water and convection. However, as shown in
The detailed description is set forth with reference to the accompanying drawings. In some instances, 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. Throughout this disclosure, depending on the context, singular and plural terminology may be used interchangeably.
The systems and methods disclosed herein provides improved thermal efficiency. For example, in certain embodiments, a water heater includes a single horse-shoe-shaped plenum in conjunction with a multi-pass heat exchanger that has additional third-pass flue tubes, which increases thermal efficiency in a water tank. In some instances, the water tank may be a 120 gallon water tank. In other instances, the water tank may be less than or greater than 120 gallons. The water tank may be generally cylindrical or the like. The water tank may be any suitable size, shape, or configuration.
Turning now to the drawings, an example water heating system and method of heating water in accordance with aspects of the present disclosure will now be described in greater detail with reference to
In some embodiments, the top cover assembly 504 includes top flues that interface with second-pass and third-pass flue tubes of the multi-pass heat exchanger. The multi-pass heat exchanger has a configuration that allows the location of the water outlet 510 in the top cover assembly 504 at the top end of the water heater 500. The bottom assembly 506 may also include a bottom flue that interfaces with the third-pass flue tubes of the multi-pass heat exchanger, where the hot gas exits the water heater 500 through a hot gas outlet in the bottom assembly 506.
During operation of the water heater 500, unheated water enters the water tank 502 through the water inlet 512, and gas is heated by the combustion system 508. The unheated water gets heated inside the water tank by hot gas flowing through the multi-pass heat exchanger. The resulting heated water exits the water tank 502 through the top water outlet 510 in the top cover assembly 504. The hot gas that flows through the multi-pass heat exchanger may exit the water tank through a hot gas outlet in the bottom assembly 506.
The water heater 500 provides a top water outlet location along with the high efficiency of a multi-pass heat exchanger. By providing the top water outlet 510, the water heater 500 provides a fuel-fired water heater with a top water outlet location that is preferable in some installations.
In some embodiments, the water heater 500 and/or one or more components of the water heater 500 may have a different shape than shown without departing from the scope of this disclosure. In some alternative embodiments, the water inlet 512 may be at a different location than shown without departing from the scope of this disclosure. In some alternative embodiments, the top water outlet 510 may be at a different location on the top cover assembly than shown without departing from the scope of this disclosure.
In embodiments, the multi-pass heat exchanger 602 utilizes a down fire combustion system (not shown in the figure), such as combustion system 508 (or any other combustion system described herein), mounted to a top portion 643 the multi-pass heat exchanger 602. The combustion system is coupled to the first-pass flue tube 604 such that the heat produced by the combustion system is expelled downwards into the first-pass flue tube 604. The first-pass flue tube 604 may include a 6″ diameter wedge portion connected to an 8″ diameter inch expansion portion, which may extend down the length of the first-pass flue tube 604. These dimensions are merely exemplary and the first-pass flue tube 604 may also be configured in any other size as well.
The first-pass flue tube 604 may also be supported by a support pipe 640, which may be welded to the heat exchanger 602. The support pipe 641 may not necessarily include an aperture, but rather may merely serve as a mechanism to support the first-pass flue tube 604 of the multi-pass heat exchanger 602. In some instances, the support pipe 641 may not be included and the first-pass flue tube 604 may be supported within the multi-pass heat exchanger 602 in any other suitable manner.
The heat produced by the combustion system travels down the first-pass flue tube 604 to the second-pass flue tubes 606, 608, 610, and 612. The heat then travels up the second-pass flue tubes 606, 608, 610, and 612, and into the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 via the diverter (for example, diverter 406, diverter 408, diverter 710, and/or any other diverter described herein) at the top portion 643 of the multi-pass heat exchanger 602. Finally, the heat travels down the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 and into a collector (not shown in the figure) located at a bottom portion 642 of the multi-pass heat exchanger 602. The collector allows the combustion gases to be vented out from the multi-pass heat exchanger 602 and also collects any condensate produced by the flue tubes as a byproduct of the combustion process. The collector may be a polymer material, however, other types of materials are also possible.
The multi-pass heat exchanger 602 may be more efficient than existing heat exchangers by allowing the heat of combustion gases within the heat exchanger 602 to be reduced from approximately 2100° F. to approximately 120° F. when the combustion gases are exhausted from the multi-pass heat exchanger 602 (based on the transference of the heat from the multi-pass heat exchanger 602). For example, the heat may be approximately 1800-2100° F. in the first flue tube 604, may be approximately 1200-1400° F. upon entering the second-pass flue tubes 606, 608, 610, and 612, may be below 500° F. upon entering the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640, and may be approximately 120° F. or below upon exiting the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640, resulting in an approximately 95% efficiency of the multi-pass heat exchanger 602. The final temperature at the end of the process may also depend on the altitude in which the multi-pass heat exchanger 602 is provided and the set point of the water heater.
In embodiments, the second-pass flue tubes 606, 608, 610, and 612 may be 3″ in diameter, and the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may be 2″ in diameter. However, the size, shape, number, arrangement, etc. of the first-pass flue tube 604, second-pass flue tubes 606, 608, 610, and 612, and third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 is merely exemplary. For example, in other embodiments, the number of second-pass flue tubes may be increased from four to six and the number of third-pass flue tubes may be decreased.
Additionally, the second-pass flue tubes 606, 608, 610, and 612 may also include one or more baffles to slow the progression of the combustion heat through the second-pass flue tubes 606, 608, 610, and 612, which provides for maximum transference of heat form the heat exchanger 602 to the water in the water heater. Baffles may also be provided within the first-pass flue tube 604, the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640, and/or in any other combination of the different flue tubes.
In some embodiments, the second-pass flue tubes 606, 608, 610, and 612 extend out radially from the first-pass flue tube 604 and curve/turn generally upward toward the top opening of the water tank 502. This is more clearly shown in
As used herein, the phrase “horse-shoe-shaped plenum” refers to the three-dimensional volume of the plenum having a semi ring torus, partial annulus, or similar shape. That is, the plenum has a curved or semi-circular profile in which opposed ends are positioned at least at 180 degrees from one another, relative to the circle defining the semi-circular profile, and in which the opposed ends are separated from one another so as not to make contact with one another.
Returning to
In some embodiments, the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may extend in the cavity of the water tank 502 from the top end of the water tank 502 to a bottom end of the water tank 502. Top end openings of the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may be terminated or may otherwise be in fluid communication with the horse-shoe-shaped top plenum 702 in the top cover assembly 504. Hot gas from the second-pass flue tubes 606, 608, 610, and 612 flows to the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 through the horse-shoe-shaped top plenum 702 in the top cover assembly 504.
In some embodiments, the bottom end openings of the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may be terminated in the bottom assembly 506 through openings in a top cover 642 of the bottom assembly 506. For example, the bottom assembly 506 may include a bottom flue 704, and hot gas flowing through the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may flow to the bottom flue 704 and exit the bottom assembly 506 through a hot gas outlet 310 of the bottom assembly 506.
In some embodiments, the first-pass flue tube 604, the second-pass flue tubes 606, 608, 610, and 612, and the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may be configured with respect to each other to allow for placing the hot water outlet 510 in the top cover assembly 504 of the water heater 500. For example, the second-pass flue tubes 606, 608, 610, and 612 may be intermingled with the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 around the first-pass flue tube 604. The second-pass flue tubes 606 and 608 are less than ninety degrees apart from each other relative to the circle defining a cross-section of the hot water heater 500, and the second-pass flue tubes 610 and 612 are less than ninety degrees apart from each other relative to the circle defining the cross-section of the hot water heater 500. Further, the second-pass flue tubes 606 and 608 are each greater than 90 degrees apart from the second-pass flue tubes 610 and 612 relative to the circle defining the cross-section of the hot water heater 500. Each second-pass flue tube 606, 608, 610, and 612 is also flanked by one of the third-pass flue tubes 614, 616, 618, 620, 630, 632, 634, and 636, where two of the third-pass flue tubes 614, 616, 618, 620, 630, 632, 634, and 636 are interspersed between two of the second-pass flue tubes 606, 608, 610, and 612. Further, the third-pass flue tubes 622, 624, 626, and 628 are disposed in area 640 between the third-pass flow tubes 620 and 630.
In general, the third-pass flue tubes 614, 616, 618, 620, 630, 632, 634, and 636 are each spaced from an adjacent one of the second-pass flue tubes 606, 608, 610, and 612 by the same circumferential distance relative to the circle defining the cross-section of the hot water heater 500. As such, compared to third-pass flue tubes that are between second-pass flue tubes and that are separated by less than ninety degrees relative to the circle defining the cross-section of the hot water heater 500, a much larger circumferential space relative to the circle defining the cross-section of the hot water heater 500 exists between third-pass flue tubes 614 and 636 that are between second-pass flue tubes 606 and 612. The much larger circumferential space relative to the circle defining the cross-section of the hot water heater 500 between the third-pass flue tubes 614 and 636 aligns with the top water outlet 510, as shown in
In contrast with typical water heaters discussed above with reference to
In some alternative embodiments, the second-pass flue tubes 606, 608, 610, and 612 and the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640 may be interspersed with each other in a different arrangement without departing from the scope of this disclosure. In some alternative embodiments, the flue tubes of the heat exchanger 602 may have different absolute and relative dimensions without departing from the scope of this disclosure. In some alternative embodiments, the heat exchanger 602 may include fewer or more flue tubes than shown without departing from the scope of this disclosure. In some instances, the second-pass flue tubes may include a 3″ outer diameter, and the third-pass flue tubes may include a 2″ outer diameter. Multiple combination of tube sizes can be accommodated and may be used herein. For example, larger tanks and diverters may allow for larger tubes. The tubes may be any suitable size, shape, or configuration.
Referring to
In some embodiments, the flue cover 708 and the tank cover plate 712 may define the horse-shoe-shaped top plenum 702. The gasket 714 may provide a more reliable seal of the horse-shoe-shaped top plenum 702. This will be described in greater detail with reference to
Referring to
To illustrate, the tank cover plate 712 may have tube holes 804, 806, 808, and 810 that are sized to receive the second-pass flue tubes 612, 610, 608, and 606, respectively. The tank cover plate 712 may have tube holes 812, 814, 816, 818, 820, 822, 824, 826, 828, 830, 832, 834, 836, and 838, that are sized to receive the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640, respectively. The tank cover plate 712 also includes a water outlet hole 802 that may be aligned with the top water outlet 510 of the water heater 500. For example, a water outlet pipe may be extended down into the water tank 502 through the water outlet hole 802. By arranging the tube holes 804, 806, 808, and 810 and the tube holes 812, 814, 816, 818, 820, 822, 824, 826, 828, 830, 832, 834, 836, and 838 to correspond to the second-pass flue tubes 612, 610, 608, and 606 and the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640, respectively, an adequate area is provided between the tube holes 812 and 838 of the tank cover plate 712 to place the water outlet hole 802 such that the water heater 500 can include the top water outlet 510 in the top cover assembly 504. In some instances, the water outlet hole 802 may include a 1.5″ connection. Smaller connections can be accommodated. Larger size tanks can accommodate larger connections. The water outlet hole 802 may be any suitable size, shape, or configuration.
In some embodiments, a central opening 840 may be positioned to align with the first-pass flue tube 604 and to receive a mounting flange 844 above the first-pass flue tube 604, as shown in
In some embodiments, mounting standoffs, such as a mounting standoff 842 may be used to securely attach the flue cover 708 to the tank cover plate 712 using, for example, screws. By using the mounting standoffs, screws that are used to attach the flue cover 708 to the tank cover plate 712 can avoid penetrating through the tank cover plate 712.
The mounting lip 910 includes a plurality of screw holes. In this instance, the mounting lip 910 includes screw holes 920, 911, 924, 926, 928, 930, 932, and 934 about the outer periphery 912 of the semicircular portion 902, and includes screw holes 936, 938, 940, 942, 944, and 946 about the inner periphery 916 of the semicircular portion 902. These screw holes enable the flue cover 708 to be fastened to the tank cover plate 712 using fasteners. The mounting lip 910 additionally includes divots 948 and 950, which may provide clearance for various other components.
As shown in
The first protrusion 954 is continuous and circumscribes the outer periphery 912 of the semicircular portion 902, the outer periphery 914 of the end 904, the inner periphery 916 of the semicircular portion 902, and the outer periphery 918 of the end 906. Similarly, the second protrusion is continuous and circumscribes the outer periphery 912 of the semicircular portion 902, the outer periphery 914 of the end 904, the inner periphery 916 of the semicircular portion 902, and the outer periphery 918 of the end 906. Thus, the gasket track 952 formed by the first protrusion 954 and the second protrusion 956 is continuous and circumscribes the outer periphery 912 of the semicircular portion 902, the outer periphery 914 of the end 904, the inner periphery 916 of the semicircular portion 902, and the outer periphery 918 of the end 906.
Further, the gasket track 952 has a plurality of bump-outs. In this instance, the gasket track 952 includes a bump-outs 958, 960, 962, and 964, each of which locally enlarge the horse-shoe-shaped plenum 702 to receive the slightly larger in diameter second-pass flue tubes 612, 610, 608, and 606, respectively.
In some embodiments, the horse-shoe-shaped diverter 710 may be positioned on the tank cover plate 712 covering the second-pass flue tubes 612, 610, 608, and 606 and the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640. As described with respect to
Because the flue tubes of the heat exchanger 602 are matched with respective holes of the tank cover plate 712, horse-shoe-shaped diverter 710 covers the second-pass flue tubes 612, 610, 608, and 606 and the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640 and defines a top flue structure together with the tank cover plate 712. The horse-shoe-shaped top plenum 702 defines one hot gas flow path from the second-pass flue tubes 612, 610, 608, and 606 to the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640.
To illustrate, the hot gas is provided by the combustion system 508 through the first-pass flue tube 604, where the hot gas flows to the second-pass flue tubes 612, 610, 608, and 606 and is routed through the horse-shoe-shaped top plenum 702 to the third-pass flue tubes 638, 636, 634, 632, 630, 628, 626, 624, 622, 620, 618, 616, 614, and 640. The hot gas is then transferred to the bottom flue 704 and exits through the hot gas outlet 718.
In some alternative embodiments, the heat exchanger 602 may include fewer or more flue tubes than shown and the tank cover plate 712 may have corresponding number of openings without departing from the scope of this disclosure.
In one instance, let line 1002 be a reference line of angle 0° about a center point 1004 of the horse-shoe-shaped diverter 710. The screw holes 924, 926, 928, 930, 932, 934, 920, and 922 are disposed at angles of 20°, 66°, 115°, 160°, 200°, 243°, 289°, and 340°, respectively, from the line 1002 about the center point 1004. Further, each of the screw holes 924, 926, 928, 930, 932, 934, 920, and 922 are disposed at an outer radius 1006, from the center point 1004, of about 12.8 inches.
In this instance, the screw holes 938, 940, 942, 944, 946, and 936 are disposed at angles of 0°, 66°, 115°, 180°, 243°, and 289°, respectively, from the line 1002 about the center point 1004. Each of the screw holes 938, 940, 942, 944, 946, and 936 are disposed at an inner radius 1008, from the center point 1004, of about 6.8 inches.
It should be noted that any number of screw holes may be used herein. More so, the screw holes may be disposed at any radius and angle about the horse-shoe-shaped diverter.
In this instance, the semicircular portion 902 has an outer radius 1010, from the center point 1004, of about 13.3 inches, and an inner radius 1012, from the center point 1004, of about 6.5 inches.
Further, in this instance, each of the divots 948 and 950 have a curvature corresponding to a radius of about 0.5 inches.
In some instances, the horse-shoe-shaped diverter 710 includes a basic dimension of about 26.6 inches. The horse-shoe-shaped diverter 710 can be any suitable size, shape, or configuration. The horse-shoe-shaped diverter 710 can be scaled for larger or smaller heat exchanger systems.
The first protrusion 954 and the second protrusion 956 may include rounded inner corners at their respective bottom edges. For example, in some instances, the first protrusion 954 may include a rounded inner corner 1104 having a radius of curvature of about 0.070 inches, whereas the second protrusion 956 may include a rounded inner corner 1106 having a radius of curvature of about 0.060 inches. Further, in some instances, the distance from a surface 1108 of the mounting lip 910 to a base 1110 of the gasket track 952 may be about 0.502 inches.
The dimensions shown in
A method 1200 of heating water in accordance with aspects of the present disclosure will now be described in greater detail with reference to
Returning to
Returning to
The somewhat-cooled hot air from the first-pass flue tube 604 is then passed upward through the second-pass flue tubes 606, 608, 610, and 612, each of which additionally heats the water surrounding the respective second-pass flue tubes 606, 608, 610, and 612. Again, by heating the water surrounding the second-pass flue tubes 606, 608, 610, and 612, the somewhat-cooled hot air is then further cooled.
The further cooled hot air from the second-pass flue tubes 606, 608, 610, and 612 is diverted by the single horse-shoe-shaped top plenum 702 and into the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640.
The further-cooled hot air from the second-pass flue tubes 606, 608, 610, and 612, is then passed downward toward the bottom of the water heater 500 through the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640, each of which additionally heats the water surrounding the respective the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640. Again, by heating the water surrounding the third-pass flue tubes 614, 616, 618, 620, 622, 624, 626, 628, 630, 632, 634, 636, 638, and 640, the further-cooled hot air is then still further cooled.
Accordingly, a portion of water in the water heater 500 that is surrounding the flue tubes is heated by conduction via the multiple passes of the hot air through the multiple flue tubes. The remainder of the water in the water heater 500 is heated via a combination of conduction with the heated water and convection. However, as shown in
Returning to
A water heater in accordance with aspects of the present disclosure includes a multi-pass heat exchanger that has a top plenum that provides a first hot gas flow path from a set of second-pass flue tubes to a set of third-pass flue tubes, wherein the set of second-pass flue tubes comprises an integer number n flue tubes, wherein the set of third-pass flue tubes comprises an integer number m flue tubes, and wherein m>2*n. In other words, the number of third-pass flue tubes are greater than twice the number of second-pass flue tubes. This is to be contrasted with the water heater as discussed above with reference to
Because the water heater in accordance with the present disclosure includes a single, horse-shoe-shaped plenum and a set of second-pass flue tubes that comprises an integer number n flue tubes, and a set of third-pass flue tubes that comprises an integer number m flue tubes, and wherein m>2*n, the thermal efficiency is increased as more areas within the water tank are filled with flue tubes as discussed above with reference to
It should be apparent that the foregoing relates only to certain embodiments of the present application and that numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the disclosure.
Although specific embodiments of the disclosure have been described, numerous other modifications and alternative embodiments are within the scope of the disclosure. For example, any of the functionality described with respect to a particular device or component may be performed by another device or component. Further, while specific device characteristics have been described, embodiments of the disclosure may relate to numerous other device characteristics. Further, although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the embodiments. 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.
This application claims priority to and benefit of U.S. provisional patent application No. 63/428,198 filed Nov. 28, 2022, which is herein incorporated by reference.
Number | Date | Country | |
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63428198 | Nov 2022 | US |