Patent Application
20100221675
The present invention relates to a hydronic boiler or water heater and a method of operating the same.
Hydronic boilers operate by way of heating water (or any other fluid) to a preset temperature and circulating the water throughout a building or a home typically by way of radiators, baseboard heaters, and so forth. Hydronic boilers typically include a burner for introducing hot combustion gases into a housing of the boiler, and a heat exchanger including hollow tube members fitted within the boiler housing. Water is circulated through the hollow tube members of the heat exchanger for heat exchange with the hot combustion gases introduced into the boiler housing.
Hydronic boilers may also be referred to as condensing boilers when they are configured to condense the water vapor in the combustion gases to capture the latent heat of vaporization of the water produced during the combustion process. When water vapor condenses to a liquid phase onto a surface of the tube members, latent energy is released as sensible heat onto the surface of the tube members.
There is a need to further refine boilers to improve at least one of their performance, efficiency, cost and reliability. Furthermore, there is a need for such a boiler which also provides for easy cleaning of the interior of the hollow tube members of the heat exchanger.
In one exemplary aspect, a boiler is provided. The boiler comprises a housing defining an enclosed region and a plurality of heat exchange conduits at least partially positioned within the enclosed region of the housing. Each heat exchange conduit has a first end spaced apart from a second end thereof and a water passageway defined between the first end and the second end. The plurality of heat exchange conduits are arranged into an interior column and an exterior column, wherein each column includes at least one heat exchange conduit. A burner is positioned to deliver products of combustion into the enclosed region of the housing for heat exchange with water contained within the plurality of heat exchange conduits. A baffle is at least partially positioned within the enclosed region of the housing and positioned between the interior column and the exterior column of the heat exchange conduits. The baffle and the housing together define a constricted region and the at least one heat exchange conduit of the exterior column is positioned within the constricted region. The constricted region being configured to direct the flow of products of combustion adjacent the at least one heat exchange conduit of the exterior column thereby facilitating the exchange of heat between the products of combustion and water within the at least one heat exchange conduit of the exterior column.
In another exemplary aspect, an inlet conduit coupled to introduce water into the first end of the at least one heat exchange conduit of the exterior column. An outlet conduit is positioned to deliver water from either the first end or the second end of the at least one heat exchange conduit of the interior column. A bypass conduit is coupled to direct at least a portion of the water from the inlet conduit into either the first end or the second end of the at least one heat exchange conduit of the interior column or the exterior column, wherein the inlet conduit, outlet conduit and the bypass conduit are positioned at least partially outside of the enclosed region.
In yet another exemplary aspect, a method of operating a boiler is provided. The method comprises the step of introducing water into a first conduit of a heat exchanger of a boiler. Water is transferred from the first conduit to a second conduit of the heat exchanger, wherein the exterior surfaces of the first conduit and the second conduit are physically separated by a baffle. Products of combustion are delivered into an enclosed region of the boiler housing for heat exchange with water contained within the second conduit. The products of combustion are directed into a constricted region of the boiler housing defined between the baffle and the boiler housing for heat exchange with water contained within the first conduit.
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following figures:
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 to the illustrated embodiments within the scope and range of equivalents of the claims and without departing from the invention. Also, the embodiments selected for illustration in the figures are not shown to scale and are not limited to the proportions shown.
Referring generally to the figures and according to one exemplary aspect of the invention, a boiler 10 is provided. The boiler 10 comprises a housing 12 defining an enclosed region and a plurality of heat exchange conduits 30, 130 and 32, 132 at least partially positioned within the enclosed region of the housing 12. Each heat exchange conduit 30, 130 and 32, 132 has a first end 30a and 32a, respectively, spaced apart from a second end 30b and 32b, respectively, thereof and a water passageway defined between the first end 30a and 32a and the second end 30b and 32b. The plurality of heat exchange conduits 30, 130 and 32, 132 are arranged into an interior column C1 and an exterior column C2, wherein each column includes at least one heat exchange conduit. A burner 20 is positioned to deliver products of combustion into the enclosed region of the housing 12 for heat exchange with water contained within the plurality of heat exchange conduits 30, 130 and 32, 132. A baffle 31, 131 is at least partially positioned within the enclosed region of the housing 12 and positioned between the interior column C1 and the exterior column C2 of the heat exchange conduits 30, 130 and 32, 132. The baffle 31, 131 and the housing 12 together define a constricted region ‘C’ and the at least one heat exchange conduit 32, 132 of the exterior column C2 is positioned within the constricted region ‘C.’ The constricted region ‘C.’ The constricted region ‘C’ defines a path for directing the flow of products of combustion adjacent the at least one heat exchange conduit 32, 132 of the exterior column C2 thereby facilitating the exchange of heat between the products of combustion and water within the at least one heat exchange conduit 32 of the exterior column C2.
In another exemplary aspect, an inlet conduit 16 is configured to introduce water into the first end of the at least one heat exchange conduit 32, 132 of the exterior column C2. An outlet conduit 18 is positioned to deliver water from either the first end 30a or the second end 30b of the at least one heat exchange conduit 30, 130 of the interior column C1. A bypass conduit 26 is coupled to direct at least a portion of the water from the inlet conduit 16 into either the first end 30a, 32a or the second end 30b, 32b of the at least one heat exchange conduit 30, 130 or 32, 132 of the interior column C1 or the exterior column C2, wherein the inlet conduit 16, outlet conduit 18 and the bypass conduit 26 are positioned at least partially outside of the enclosed region of the housing 12.
In yet another exemplary aspect, a method of operating a boiler 10 is provided. The method comprises the step of introducing water into a first conduit 32, 132 of a heat exchanger 14, 114 of a boiler 10. Water is transferred from the first conduit 32, 132 to a second conduit 30, 130 of the heat exchanger 14, 114, wherein the exterior surfaces of the first conduit 32, 132 and the second conduit 30, 130 are physically separated by a baffle 31, 131. Products of combustion are delivered into an enclosed region of the boiler housing 12 for heat exchange with water contained within the second conduit 30, 130. The products of combustion are directed into a constricted region ‘C’ of the boiler housing 12 defined between the baffle 31, 131 and baffle 31, 131 and the boiler housing 12 for heat exchange with water contained within the first conduit 32, 132.
Referring now to
The housing 12 of the boiler 10 generally includes a top cover 17, three walls 19 (right side wall shown; left side wall and rear wall not shown), a front panel 36, and a lower panel 57 (see
In use, a supply of unheated or heated water (or any other suitable liquid) is delivered into the boiler 10 through the inlet conduit 16. The inlet conduit 16 includes an outlet port 24 for delivering water into one side of the heat exchanger 14. A bypass conduit 26 is fluidly coupled to a bypass port 22 of the inlet conduit 16. The bypass conduit 26 is configured to deliver water into the opposite side of the heat heat exchanger 14. Optionally, the bypass conduit 26 can be configured to deliver water into an inner conduit on the same side of the heat exchanger 14.
A valve 28 is mounted to the bypass conduit 26 for selectively permitting water to flow through the bypass conduit 26. In the open position of the valve 28, water is permitted to flow through the bypass conduit 26, and in a closed position of the valve 28, water is restricted from flowing through the bypass conduit 26. The purpose of the valve 28 and the bypass conduit 26 will be described in greater detail with respect to
The heat exchanger 14 may be referred to as a “two-pass” heat exchanger. More particularly, at least a portion of the water delivered through the inlet conduit 16 makes a first pass through the secondary heat exchange conduits 32 and is preheated by the products of combustion passing over the secondary heat exchange conduits 32. By way of example, about 20% to about 25% of the thermal energy of the products of combustion is transferred to the water within the secondary heat exchange conduits 32. The preheated water then makes a second pass through the primary heat exchange conduits 30 and is heated by the products of combustion passing over the primary heat exchange conduits 30. By way of example, about 75% to about 80% of the thermal energy of the products of combustion is transferred to the water within the heat exchange conduits 30.
The heat exchanger includes ten primary heat exchange conduits 30(1) through 30(10) (referred to collectively as conduits 30) and ten secondary heat exchange conduits 32(1) through 32(10) (referred to collectively as conduits 32). Alternatively, the heat exchanger includes eight primary heat exchange conduits and eight secondary heat exchange conduits. Additionally, smaller and larger numbers of conduits are contemplated as well, depending on the size or capacity of the system. Also, the number of primary and secondary conduits can be the same (as illustrated) or their numbers may be different. For example, there may be a larger number of primary or secondary conduits as compared to secondary and primary conduits, respectively.
Each conduit 30 and 32 includes a first end portion 30a and 32a, respectively, spaced apart from a second end portion 30b and 32b, respectively. A hollow liquid passageway having a circular cross-section is defined between the first end portion 30a and 32a and the second end portion 30b and 32b of each conduit 30 and 32, respectively. The cross-sectional shape of the liquid passageway may vary without departing from the scope or spirit of the invention. Although not shown, each conduit 30 and 32 may include heat sink fins extending from or forming part of its exterior surface (see
The conduits 30 and 32 are arranged into two vertical columns C1 and C2. In assembled form, the exterior column C2 of conduits 32 surrounds or extends about the interior column C1 of conduits 30. According to the exemplary embodiment illustrated herein, each column C1 and C2 includes ten conduits 30 and 32, respectively. The heat exchanger 14 may include any number of conduits 30 and 32, and is thereby not limited to a specific number of conduits 30 and 32. The conduits 30 and 32 of each column C1 and C2, respectively, may optionally be fastened together by a weld, clamp, bracket, mechanical fastener, strap, or any other fastening means known to those skilled in the art.
The baffle 31 is positioned to extend between the columns C1 and C2 of conduits 30 and 32, respectively. The column C1 of conduits 30 are positioned within the baffle 31, whereas the column C2 of conduits 32 are positioned outside of the baffle 31. In this exemplary embodiment, the baffle 31 includes a single “U” shaped wall 40 positioned to extend between the columns C1 and C2 of “U” shaped conduits 30 and 32, respectively. As will be described with reference to
The baffle 31 includes a floor surface 49 for limiting or preventing inadvertent escape of combustion products through the lower end of the heat exchanger 14. Opposite the floor surface 49, the top end of the baffle 31 is exposed for inducing the flow of combustion products over the wall 40 of the baffle 31 as described in greater detail with reference to
The front panel 36 is mounted to the baffle 31 by a swaging operation. Alternatively, the front panel 36 may be mounted to the baffle 31 by a series of fasteners (not shown). An aperture 43 is defined in the center of the front panel 36 for accommodating the burner 20 (see
Two header mounting plates 42 and 44 are mounted to the front panel 36 by a series of fasteners. Two headers 48 and 50 are mounted to the header mounting plates 42 and 44, respectively, by a series of fasteners (not shown) or any other means for fastening known to those skilled in the art. The headers 48 and 50 conceal the exposed ends of the conduits 30 and 32. Although not shown, a compressible, elastomeric gasket may be positioned at the interface between each header 48 and 50 and its respective header mounting plate 42 and 44, respectively, for limiting leakage of water.
The first header 48 includes a inlet opening 52 for coupling with the outlet port 24 of the inlet conduit 16. The second header 50 includes a secondary inlet opening 54 for coupling with the an outlet port 27 of the bypass conduit 26. The second header 50 further includes an outlet opening 56 for coupling with the outlet conduit 18 and providing a passageway for removing heated water from the conduits 30 and 32 of the heat exchanger 14.
In assembled form, the conduits 30 are coupled (either directly or indirectly) to the front plate 36 of the housing 12 and both header mounting plates 42 and 44. According to one exemplary method of assembling heat exchanger 14, the first end portion 30a of each conduit 30 is sequentially positioned through a respective aperture 34(III) defined on a flange of the front plate 36 and a respective aperture 38(III) defined on the header mounting plate 42. Similarly, the second end portion 30b of each conduit 30 is sequentially positioned through a respective aperture 34(II) defined on the front plate 36 and a respective aperture 38(II) defined on the header mounting plate 44.
The conduits 32 are coupled (either directly or indirectly) to the baffle 31, the front plate 36, and both header mounting plates 42 and 44. More particularly, the first end portion 32a of each conduit 32 is sequentially positioned through a respective aperture 39(II) defined on a flange of the baffle 31, a respective aperture 34(IV) defined on the front plate 36, and a respective aperture 38(IV) defined on the header mounting plate 42. Similarly, the second end portion 32b of each conduit 32 is sequentially positioned through a respective aperture 39(I) defined on the flange of the baffle 31, a respective aperture 34(I) defined on the front plate 36, and a respective aperture 38(I) defined on the header mounting plate 44.
According to one aspect of the invention and as best shown in
Swaging the end portions 30a, 30b, 32a and 32b, as shown, captivates the conduits 30 and 32 to the baffle 31, the front plate 36, and both header mounting plates 42 and 44. Additionally, the end portions 30a, 30b, 32a and 32b of the conduits are swaged for accomplishing a liquid-tight seal between the header mounting plate 42 and 44 and the swaged end portions 30a, 30b, 32a and 32b. As shown in
A lower refractory panel 47 is positioned between the bottom conduit 30(10) and the floor 49 of the baffle 31. Similarly, a top support panel 51 is positioned between the top conduit 30(1) and the top cover 17 of the housing 12. The upper support panel 51 and the lower refractory panel 47, respectively, are optionally mounted to the conduits by a series of straps 53 (two shown) for added structural support. It should be understood that a variety of ways exist for mounting the upper and lower panels 51 and 47 to the conduits 30.
The exterior column C2 of conduits 32 is positioned outwardly from the interior column C1 of conduits 30. It follows that the horizontal distance between the first end portion 32a and the second end portion 32b of each conduit 32 is greater than the horizontal distance between the first end portion 30a and the second end portion 30b of each conduit 30. The baffle 31 is positioned between the columns C1 and C2 of conduits 30 and 32, respectively. The baffle 31 is substantially “U”-shaped for for mounting between the “U”-shaped columns C1 and C2. It should be understood that the shape of the baffle 31 may depart from that shown to conform to the shape of the conduits 30 and 32.
The partitions 60 and 62 are positioned to retain water in a respective channel. Each partition 60 and 62 is a solid wall that extends the entire width “W” of the header 48 and 50 (see
The purpose of the headers 48 and 50, the partitions 60 and 62 and the channels Z1 through Z8 are best described with reference to the operation of the heat exchanger 14. According to one exemplary use of this invention, water is first introduced into the inlet conduit 16 (see
Upon entering the channel Z1, the water fills the channel Z1 and flows into the first end of conduits 32(1) and 32(2). In
Water is also introduced into the channel Z6 through the bypass opening 54 of the second header 50. By way of non-limiting example, about approximately 20% of the water introduced into the heat exchanger 14 flows into the inlet opening 52 of the first header 48, and the remaining portion of the water flows into the bypass opening 54 of the second header 50. A lower proportion of the water is introduced through through the inlet opening 52 in an effort to reduce the pressure drop through the exterior column of conduits 32. The relative proportions of water flow, however, may be altered through adjustment of the valve 28 provided on the bypass conduit 26.
Both sources of water, either alone or in combination, fill the channel Z6 and flow into the second end of conduits 30(6), 30(7), 30(8), 30(9) and 30(10). The water then travels through conduits 30(6), 30(7), 30(8), 30(9) and 30(10) and exits into channel Z7 of the first header 48. The water fills the channel Z7 and flows into the first end of conduits 30(1), 30(2), 30(3), 30(4) and 30(5). The channel Z7 includes the first ends of the entire interior column C1 of conduits 30. The water then travels through conduits 30(1), 30(2), 30(3), 30(4) and 30(5) and exits into channel Z8 of the second header 50. The water fills the channel Z8 of the second header 50 and flows into the outlet opening 56 provided in the second header 50. The water is ultimately carried away by the outlet conduit 18 that is coupled to the outlet opening 56 of the second header 50.
Those skilled in the art will recognize that various ways exist to direct the flow of water through the conduits 30 and 32 without departing from the scope or spirit of the invention, and the invention is not limited to any particular flow path.
The flow of combustion products along a defined flow passageway is depicted by a series of arrows labeled ‘1’ through ‘6’ in
The products of combustion are then induced to flow between gaps (not shown) provided between the exterior surfaces of adjacent conduits 30. These gaps are optionally defined by fins formed on the conduits 30. The gaps may also be provided by spaces defined between the conduits 30. The products of combustion are then urged or forced to flow in an upward direction and along the opposite surface of the conduits 30 as indicated by the vertical arrows labeled ‘2.’ The products of combustion are then induced to flow through the gap “G” provided between the top cover 17 of the housing 12 and the top edge of the wall 40 of the baffle 31, as baffle 31, as indicated by the horizontal arrows labeled ‘3.’
The products of combustion are then induced to flow through the constricted region “C” defined between the baffle wall 40 and the partition 72 of the boiler housing 12, as indicated by the vertical arrows labeled ‘4.’ The conduits 32 are positioned within the constricted region “C.” Heat from the products of combustion is transferred to the water within the conduits 32 through convective heat transfer. By way of example, about 20% to about 25% of the thermal energy of the products of combustion is transferred to the water within the conduits 32. The purpose of the constricted region “C” will be described in greater detail later.
After passing through the constricted region “C,” the products of combustion collect in an exhaust chamber 74 positioned beneath the heat exchanger 14, as indicated by the horizontal arrows labeled ‘5.’ The exhaust chamber 74 is bounded by the lower panel 57 of the boiler housing 12, the lower portion of the partition 72 and the floor 49 of the baffle 31. The products of combustion are then drawn through an exhaust opening 76 provided in the lower panel 57 of the boiler housing 12, as indicated by the vertical arrow labeled ‘6.’ The exhaust opening 76 is positioned proximal to and in flow communication with the constricted region “C.” Although not shown, an exhaust conduit may be coupled to the exhaust opening 76 for removing the products of combustion from the boiler 10.
As indicated previously, the products of combustion are induced to flow through the constricted region “C” defined between the baffle wall 40 and the partition 72 of the boiler housing 12, as indicated by the vertical arrows labeled ‘4.’ Both the total volume and cross-sectional area of the constricted region “C” is significantly less than the total volume and cross-sectional area of the interior portion 70 of the housing 12 circumscribed by the interior column of conduits 30, as depicted by the cross-sectional view of
Upon entering the constricted region “C,” the velocity of the combustion products substantially increases as a result of the reduced cross-sectional area of the constricted region “C.” By way of example, the velocity of the products of combustion in the interior portion 70 of the housing 12 is about 1.1 feet/second and the velocity of the products of combustion in the constricted region “C” is about 6.4 feet/second. The high-velocity products of combustion within the constricted region “C” results in a greater heat exchange between the products of combustion and the water within the exterior column of conduits 32. By way of example, about 20% to about 25% of the thermal energy of the products of combustion is transferred to the water within the conduits 32.
The products of combustion flowing through the constricted region “C” release sufficient heat to cause the water vapor in the products of combustion to condense on the outer surfaces of the conduits 32. As background, condensate is introduced through combustion as a byproduct of the combustion reaction, and hot combustion gases therefore contain relatively large quantities of moisture. When the hot combustion gas is cooled, the temperature of the gas drops. As this occurs, the amount of moisture that the gas can hold decreases and at some distance from the combustion source, the water condenses on any surface that is below the dew point of the gas mixture. The dew point is the temperature to which a given parcel of air must be cooled, at constant barometric pressure, for water vapor to condense into water. Hydronic boilers are tailored to condense the water vapor in the combustion gases to capture the latent heat of vaporization of the water produced during the combustion process. When the water vapor condenses to a liquid phase onto a surface of the conduits 32, latent energy is released as sensible heat onto the surface of the conduits 32, thereby transferring heat to the water within the conduits 32.
Condensate is typically acidic, with pH values often in the range of between about 2 to 5. The formation of increased amounts of such acidic condensate, even in relatively small quantities, can accelerate the corrosion of heat exchange tubing, increase oxidation and scale formation, reduce heat exchange efficiency and contribute to failure of the boiler. To limit or prevent corrosion in the presence of water, the conduits 30 and 32 are optionally formed from stainless steel, aluminum or coated copper; the header mounting plates 42 and 44 are optionally composed of carbon steel; and the front panel 36 is optionally composed of stainless steel. The headers 48 and 50 are optionally composed of carbon steel. The interior of the headers 48 and 50 and the conduits 30 and 32, or any other component of the boiler 10 in the presence of water, may be lined with glass for safely distributing potable water. It should be understood by those skilled in the art that the individual components of the boiler 10 may be formed from a variety of materials without departing from the spirit or scope of the invention.
The heat exchanger 14 confers several benefits over conventional heat exchangers. First, the heat exchanger 14 can withstand a greater quantity of condensate without exhibiting corrosion because the conduits 30 and 32 are formed from a material that resists corrosion in the presence of water. Accordingly, because introducing lower inlet water temperatures into a heat exchanger results in greater quantities of condensate and the conduits 30 and 32 are formed from a corrosion resistant material, water may be introduced into the heat exchanger 14 at a lower temperature. For example, water may be introduced into the heat exchanger 14 at 40° F., as compared with conventional boilers which are designed to receive water pre-heated or heated to a temperature of at least 130° F. Because the heat exchanger 14 can efficiently process low-temperature water, the incoming water does not have to be pre-heated, thereby resulting in a significant energy savings.
Second, increasing the velocity of the combustion products passing over the conduits 32 maximizes the heat exchange therebetween, thereby resulting in a better utilization of the heat exchange material as compared with heat exchangers of conventional boilers. Accordingly, less heat exchange material (i.e., fewer or smaller conduits 32) is required to achieve the same level of heat exchange efficiency observed in conventional boilers, thereby resulting in a significant material cost savings.
Third, the heat exchanger 14 is configured for the efficient removal of condensate from the interior of the housing 12. Although not shown, the lower panel 57 and the floor surface 49 of the baffle 31 may include a condensate outlet port, or other provisions, to facilitate the draining of condensation formed on the interior surfaces of the heat exchanger 14. A drain, tube or pipe (not shown) may be coupled to the condensate outlet port for removing the condensate from the boiler 10. Furthermore, the high-velocity products of combustion flowing through the constricted region “C” urge the condensate formed on the conduits 32 in a direction towards the aforementioned condensate removal provisions provided in the lower panel 57.
Fourth, by virtue of the unique design of the heat exchanger 14, the boiler can be configured to operate at about 93% efficiency to about 97% efficiency, as compared with traditional hydronic boilers which operate at 90% efficiency. One measurement of the efficiency of a boiler is the annual fuel utilization efficiency (AFUE). AFUE is the ratio of heat output of the boiler compared to the total energy consumed by a boiler. An AFUE of 90%, for example, indicates that 90% of the energy in the fuel becomes heat for the installation and the other 10% escapes through outlet piping.
Referring back to
By positioning the burner 20, the ends of the conduits 30 and 32, and the headers 48 and 50 on the front panel 36, multiple boilers 10 may be positioned side-by-side in an installation to save valuable floor space.
As best shown in
Unlike the baffle 31 of
The heat exchanger 114 of
Each conduit 130 and 132 includes heat-sink fins 197 longitudinally spaced along its entire length to maximize heat transfer between the products of combustion and the fluid within the conduits 130 and 132.
Unlike the heat exchanger of
Each baffle 190 includes a “U” or “V” shaped portion which is sized to fit between the revolved surface of adjacent conduits 130, as best shown in
Adjacent baffles 190 are separated by a gap 194. In use, the products of combustion flow between the fins 197 of the conduits 130 and pass through the gaps 194 provided between the conduits 130. Inducing the products of combustion through the gaps 194 maximizes heat transfer between the products of combustion and the fluid within the conduits 130.
In addition to the baffles 190, a series of baffles 195 (fourteen shown) are positioned in every interior and exterior crevice defined between adjacent conduits 132, as shown in
In use, the products of combustion flow between the fins 197 of the conduits 132. The baffles 195 direct the products of combustion toward the flow passages of the conduits 132, thereby maximizing heat transfer between the products of combustion and the fluid within the conduits 132.
Referring now to
Water is also introduced into the channel X5 through the bypass opening 154 of the second header 150. By way of non-limiting example, about approximately 20% of the water introduced into the heat exchanger 114 flows into the inlet opening 152 of the first header 148 and the remaining portion of the water flows into the bypass opening 154 of the second header 150. A lower proportion of the water is introduced through the inlet opening 152 in an effort to reduce the pressure drop through the exterior column of conduits 132. The relative proportions of water flow, however, may be altered through adjustment of a valve provided on the inlet conduit (not shown).
Both sources of water, either alone or in combination, fill the channel X5 and flow into the second end of conduits 130(5), 130(6), 130(7) and 130(8). The water then travels through conduits 130(5), 130(6), 130(7) and 130(8) and exits into channel X6 of the second header 150. The water fills the channel X6 and flows into the first end of conduits 130(1), 130(2), 130(3) and 130(4). The channel X6 includes the second ends of the entire interior column C1 of conduits 130. The water then travels through conduits 130(1), 130(2), 130(3) and 130(4) and exits into channel X7 of the first header 148. The water fills the channel X7 of the first header 148 and flows into the outlet opening 156 provided in the first header 148. The water is ultimately carried away by an outlet conduit (not shown) that is coupled to the outlet opening 156 of the first header 148. As noted previously, those skilled in the art will recognize that various ways exist to direct the flow of water through the conduits 130 and 132 without departing from the scope of spirit of the invention, and the invention is not limited to any particular flow path.
While preferred embodiments of the invention have been shown and described herein, it will be understood that such embodiments are provided by way of example only. 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.
