Water heater and method of mounting a heating element in a water heater

Abstract

A water heater and a method of installing a heating element in a fluid heating apparatus. The water heater rests in relation to the floor and includes a water tank having a wall. A mounting device is coupled to the wall of the water tank. The water heater also includes a heating element coupled to the mounting device, the heating element having a greatest cross-sectional area. The heating element cooperates with the mounting device such that coupling the heating element to the mounting device ensures the greatest cross-sectional area of the heating element is level with respect to the floor.

Description

FIELD OF THE INVENTION

The invention relates generally to a method and apparatus for mounting heating elements in a water heater. More specifically, the invention relates to a method and apparatus for assuring a particular orientation of the heating element within the water heater.

BACKGROUND

A storage-type water heater typically comprises a permanently enclosed water tank, a cylindrical shell coaxial with and radially spaced apart from the water tank to form an annular space between the outer wall of the water tank and the inner wall of the shell, and insulating material in at least a portion of the annular space for providing thermal insulation to the water tank. The water tank has various appurtenances such as inlet, outlet, and drain fittings. Additionally, the water heater is provided with a water heating and temperature control system. In electric water heaters, the water heating and temperature control system includes one or more electrical resistance heating elements.

SUMMARY

The water tank has tank characteristics that are used in determining the thermal profile of the tank. The tank characteristics may include, but are not limited to, tank diameter, tank height, tank storage capacity, etc. The tank characteristics determine heating convection current flow patterns within the tank that create different temperature water strata layers in the tank. Another characteristic that determines heating convection current flow patterns is the placement and position of the heating element in the tank. Some heating element positions improve the current flow patterns in the tank. It is thus desirable to mount the heating element within the tank in a position that maximizes the current flow patterns within the tank to increase the efficiency of the water heater.

Accordingly, and in one embodiment, the invention provides a water heater that rests in relation to the floor. The water heater includes a water tank having a wall, a mounting device coupled to the wall of the water tank, and a heating element coupled to the mounting device. The heating element includes a greatest cross-sectional area and cooperates with the mounting device such that coupling the heating element to the mounting device ensures the greatest cross-sectional area of the heating element is level with respect to the floor.

In some embodiments, the mounting device is threaded and the heating element includes mating threads. In other embodiments, at least one of the heating element and the wall of the tank includes an identification mark such that aligning the identification mark in a predetermined position results in the greatest cross-sectional area of the heating element being level with respect to the floor. In other embodiments, the mounting device includes a mounting flange and the heating element includes a heating element flange that cooperates with the mounting flange. In yet other embodiments, the water heater includes a resilient gasket placed between the cooperating mounting flange and heating element flange, and a compression element is coupled to the mating flanges, compressing the gasket therebetween to form a water-tight seal between the mounting flange and heating element flange.

The invention also provides for a method of installing a heating element in a fluid heating apparatus. The method includes providing a fluid tank within the fluid heating apparatus, the fluid tank having a wall, coupling a mounting device to a wall of the fluid tank, and coupling a heating element to the mounting device to ensure that the greatest cross-sectional area of the heating element is level with respect to the floor.

Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a water heater embodying aspects of the invention.

FIG. 2 is a top view of a heating element for use in the water heater of FIG. 1.

FIG. 3 is a side view of the heating element of FIG. 2.

FIG. 4 is a top exploded sectional view of the water heater of FIG. 1 illustrating the heating element coupled to a mounting device.

FIG. 5A is an end view of a single-start threaded connector.

FIG. 5B is a side view of the threaded connector of FIG. 5A.

FIG. 6A is an end view of a two-start threaded connector.

FIG. 6B is a side view of the threaded connector of FIG. 6A.

FIG. 7A is an end view of a three-start threaded connector.

FIG. 7B is a side view of the threaded connector of FIG. 7A.

FIG. 8A is an end view of a four-start threaded connector.

FIG. 8B is a side view of the threaded connector of FIG. 8A.

FIG. 9 is an end view of the heating element of FIG. 2, illustrating an identification mark.

FIG. 10 is a partial exploded perspective view of another construction of a water heater embodying aspects of the invention.

FIG. 11 is an enlarged view taken along line 11-11 of FIG. 10.

FIG. 12 is an enlarged view of an alternate mounting device capable of being used with the water heater of FIG. 10.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “connected,” “coupled,” and “mounted” and variations thereof herein are used broadly and, unless otherwise stated, encompass both direct and indirect connections, couplings, and mountings. In addition, the terms connected and coupled and variations thereof herein are not restricted to physical and mechanical connections or couplings.

FIG. 1 shows a sectional view of an electric water heater 10 comprising a vessel. With reference to FIG. 1, the vessel is defined as one of an enclosed water tank 11 or a shell 12 surrounding the water tank 11. Foam insulation 13 fills the annular space between the water tank 11 and the shell 12. A water inlet line or dip tube 14 and a water outlet line 15 enter the top of the water tank 11. The water inlet line 14 has an inlet opening 22 for adding cold water near the bottom of the water tank 11. The water outlet line 15 has an outlet opening 24 for withdrawing hot water from near the top of the water tank 11. The water heater 10 is configured to rest on a support surface, such as the floor 25. In the illustrated construction, the water heater 10 includes an axis A that is substantially perpendicular to the floor 25.

A heating element 16 extends through the wall of the water tank 11. In the illustrated embodiment, the heating element 16 is an electric resistance heating element. However, other types of heating elements can be used. The mounting of the heating element 16 to the wall of the water tank 11 will be described in more detail below.

The temperature control circuitry controls the heating of the water. The temperature control circuitry includes a controller (in control box 17), a temperature sensor assembly 18, and the heating element 16. In one construction, the temperature control circuitry includes a burst control circuit for providing power to the resistance heating element in bursts. The details of a burst control circuit are described in U.S. Pat. No. 6,633,726, entitled METHOD OF CONTROLLING THE TEMPERATURE OF WATER IN A WATER HEATER, issued Oct. 14, 2003, the entire disclosure of which is incorporated herein by reference. However, the temperature control circuitry can use other circuitries and other methodologies for heating the water.

In some constructions, the temperature control circuitry in control box 17 includes a programmable real time clock. Peak or off-peak energy demand periods or vacation operation cycles are programmed into the control cycle for the heating element. Additionally, a pressure sensor, temperature sensor, mineral deposit sensor and/or sensor for detecting the presence of water could be added. In one method of operation of the water heater 10, the control circuit is programmed to disconnect power from the heating element when predetermined conditions or limits are detected.

Referring again to FIG. 1, the temperature sensor assembly 18 is coupled to the outer wall of the water tank 11 to sense the temperature of water in the tank 11. The temperature sensor assembly can include one or more thermistors for sensing the temperature of the water in the tank 11. When multiple thermistors are used, the thermistors are placed throughout the tank to measure water temperature at a plurality of locations, and the output of the thermistors can be averaged. However, the temperature sensor assembly can use other types of temperature sensors and can be simply a single sensor.

The temperature sensor assembly 18 is connected to the controller, for example, by an electrical wire 19. The controller is a known control system in the art that is in communication with the heating element 16 and the temperature sensor assembly 18 and generates a signal controlling the heating element in response to the temperature sensed by the sensor assembly 18. The controller can include an integrated circuit, a programmable device, discrete circuit elements, a processor and memory that are software driven, and similar components. The controller may include a switching element (not shown), such as a thyristor or a triac, to selectively power the heating element.

Electric alternating current (A.C.) power is supplied to the water heater 10 through line 20. A customizable operator interface (not shown) can be mounted on the outside of the water heater to permit communication with the controller and provides security protected access for control of the heating element. The operator interface may be operable to provide direct or remote control of the heating element.

FIG. 2 illustrates the heating element 16 in more detail. As illustrated in FIG. 2, the heating element 16 of the illustrated embodiment is substantially U-shaped when viewed from the top. However, it is understood that any shape of heating element, such as a round or circular loop, a flat helix design, a serpentine pattern, or other shapes, can be used with the water heater 10. The heating element 16 includes a greatest cross-sectional area 26, best shown in FIG. 2.

With reference to FIGS. 2-4, the heating element 16 also includes a heating element flange 28 that mates with a mounting flange 30 of a mounting device 32 coupled to a wall of the water tank 11. As used herein, the term “flange” means not only a traditional mechanical flange, but any mount on the heating element that mates with a mount on the mounting device to assist in coupling the heating element 16 to the tank 11.

The heating element flange 28 includes threads 34. The heating element 16 further includes an electrical connector portion 36 that includes electrical contacts 40 (also shown in FIG. 9) that are in communication with the controller for controlling the heating of the water in the tank 11.

A gasket is also coupled to the heating element 16. In the illustrated embodiment, the gasket is a compressible O-ring 44 that can be made of any temperature-tolerant resilient material, such as neoprene, silicone, rubber, etc. It is understood that the gasket can be of any configuration and/or material that is capable of providing a resilient seal between the heating element 16 and the mounting device 32. The function of the O-ring 44 will be discussed in more detail below.

As mentioned above, a mounting device 32 is coupled to a wall of the water tank 11. The mounting device 32 is generally welded to a wall of the tank 11 and is configured to receive the heating element 16. As shown in FIG. 4, the mounting device 32 includes the mounting flange 30 having threads 48 that mate with the threads 34 of the heating element 16. Threading the heating element 16 into the mounting device 32 also functions to compress the O-ring 44 therebetween to form a water-tight seal between the mounting device 32 and the heating element 16.

In the illustrated construction, the threads 48 of the mounting flange 30 and the mating threads 34 of the heating element 16 are multi-lead or multi-start threads. FIGS. 5A and 5B illustrate an end view and a side view of a single-start threaded connector 50. When looking at a single-start threaded connector 50 in an end view, the threads form an offset circular shape. In contrast, with reference to FIGS. 6A, 7A, and 8A, a two-start threaded connector 52 will have a somewhat oval or football shape in an end view, a three-start threaded connector 54 will have a tri-oval shape, and a four-start threaded connector 56 will have a four-cornered shape in the end view.

The more starts or leads that the threaded connector has, the faster the mating threads will travel along the threaded connector. This occurs because using multiple starts increases the number of starting points a thread will engage in a mating part with fewer degrees of rotation, increasing the thread contact area (when compared to a thread with the same lead but using a single start). This can be illustrated in the following way: if one places a pencil in a thread groove 58 of a single-start threaded connector 50 and rotate the threaded connector 360° (i.e., one full revolution), the mark 60 left by the pencil in the groove will end in the adjacent thread groove 58 (see FIG. 5B). In contrast, placing a pencil in a groove 58 of a two-start threaded connector 52 and rotating the threaded connector 52 one full revolution will result in one groove 58 existing between the ends of the mark 60 (see FIG. 6B). Two grooves 58 will exist between the ends of the mark 60 made on a three-start threaded connector 54 (see FIG. 7B), and so on. Utilizing multi-start threads in the illustrated construction functions to speed the installation of the heating element 16 into the mounting device 32, as well as making adjustment of the heating element 16 during the threading process more precise. However, it is understood that single-start threads could be used as the mating threads 34.

In some constructions, the heating element 16 also includes an identification mark that assists a user in coupling the heating element 16 to the mounting device 32 when a particular heating element orientation within the tank 11 is desired. As illustrated in FIG. 9, the identification mark is an arrow 64 that indicates a particular heating element orientation. The arrow 64 is pointed upward with respect to the floor 25, and may include the word “Up” inside the arrow to indicate to a person installing the heating element 16 in the tank 11 what the final orientation of the heating element 16 should be. It is understood that in other constructions utilizing an identification mark, other types of marks could be used, so long as the identification mark assists in the installation of the heating element to obtain the desired final orientation of the heating element 16 in the tank 11. It is also understood that in some constructions, an identification mark may also be placed on the outside of the wall of the tank 11 instead of, or in conjunction with, the identification mark on the heating element for the same purpose. For example, the identification mark on the heating element could be a straight line mark or the bottom half of a shape (such as a semi-circle) that needs to be matched with a mating mark (e.g., a second straight line or semi-circle) found on the water tank 11 to obtain the desired final orientation of the heating element 16.

In the illustrated constructions, the desired final orientation of the heating element 16 within the tank 11 is such that the greatest cross-sectional area 26 of the heating element 16 is level with respect to the floor 25, as shown in FIGS. 1 and 4. As used herein, the term “level” means that the heating element 16 is at least substantially parallel to the ground in an upright water heater such as illustrated in FIG. 1 and that slight variations from absolute level are possible due to mechanical tolerances and slight variations in the floor and still fall within the definition of “level.” Put another way, the greatest cross-section 26 of the heating element 16 is preferably substantially perpendicular to the axis A of the water heater 10.

The level orientation results in better thermal transfer from the heating element 16 to the water in the tank 11 because the greatest cross-section 26 of the heating element 16 is exposed to convection currents within the water, thereby improving the efficiency of the convection currents. This results in an improved recovery time for the water heater 10, and increases the overall efficiency of operation of the water heater 10.

FIGS. 10 and 11 illustrate an alternate construction of a mounting device 70. Like reference numerals will be given to like parts as appropriate.

As shown in FIGS. 10 and 11, the heating element 16 includes a heating element flange 74 that mates with a mounting flange 78 of the mounting device 70. Each of the heating element flange 74 and mounting flange 78 have a plurality of apertures 82, 84 that align with each other when the heating element flange 74 is coupled to the mounting flange. The apertures are configured to receive a fastener 86 therethrough. It is understood that the fastener could be a screw, a bolt, a weldment, a rod, or any other appropriate mechanical fastening system. In the illustrated construction, five apertures 82, 84 are spaced at points around the flanges to receive up to five fasteners 86 therethrough to couple the heating element 16 to the tank 11. However, it is understood that any number of apertures and fasteners can be used to couple the heating element 16 to the tank 11.

A circular resilient gasket 90 is also provided to fit between the heating element flange 74 and mounting flange 78. The gasket 90 includes apertures 94 that align with the apertures 82, 84 in the flanges. The heating element 16 is coupled to the mounting device by aligning the apertures 82, 84 in the heating element flange 74 and mounting flange 78 with the apertures 94 in the gasket 90. Once the apertures are aligned, the fasteners 86 are placed through the apertures to couple the heating element 16 to the tank 11. The fasteners 86 are tightened to compress the gasket 90 between the flanges, forming a water-tight seal between the heating element 16 and the tank. In this way, the fasteners 86 function as a compression element, compressing the gasket 90 to form the seal.

The pattern of apertures 82, 84, 94 in the heating element flange 74, mounting flange 78, and gasket 90, respectively, function as an identification mark to assist in the installation of the heating element 16 to obtain the desired level orientation of the heating element 16 discussed in detail above. If the pattern of apertures 82 on the heating element flange 74 is matched to the pattern of apertures 84 on the mounting flange 74 when the heating element is installed, the heating element 16 of FIGS. 10 and 11 will be mounted within the tank 11 such that the greatest cross-sectional area 26 is level with respect to the floor 25. By matching the pattern of apertures 82 on the heating element flange 74 to the pattern of apertures 84 on the mounting flange 78 and the gasket 90, the operator ensures that the heating element 16 will be mounted with the desired orientation within the tank 11.

FIG. 12 illustrates yet another alternate construction of a mounting device 100. Like reference numerals will be given to like parts where appropriate.

As illustrated in FIG. 12, the heating element 16 includes a non-threaded heating element flange 104 that mates with a non-threaded mounting flange 108 of the mounting device 100. The heating element flange 104 and the mounting flange 108 are generally cylindrical in shape. The heating element flange 104 is slightly smaller in diameter than the mounting flange 108 such that the heating element flange 104 fits within the mounting flange 108 to couple the heating element 16 to the tank 11. It is understood that in other embodiments, the mounting flange might have a smaller diameter such that the mounting flange fits within the heating element flange.

The mounting flange 108 and the heating element flange 104 are designed such that the flanges will only cooperate with each other in a predetermined position to ensure that the heating element 16 is coupled to the tank 11 in the desired orientation (i.e., the heating element 16 is level with respect to the floor 25). In the illustrated construction, the mounting flange 108 includes a protrusion 112 and the heating element flange includes a channel 116 that receives the protrusion 112 when the heating element 16 is coupled to the mounting device 100. Aligning the protrusion 112 and the channel 116 to couple the heating element 16 to the tank 11 ensures the desired final orientation of the heating element. It is understood that in other constructions, the protrusion could be located on the heating element flange and the channel located on the mounting flange. It is also understood that other types of mating mechanisms could be used on the heating element flange and mounting flange to ensure the desired orientation. For example, the protrusion can be a bump that cooperates with a channel, a notch, or other aperture, the protrusion could be a rod, nail, screw, weldment, or bolt that is received by a notch, channel, or other aperture, or the mating mechanism could be a ball and spring detent mechanism as is well known in the art. In other constructions, multiple protrusions of various geometrical configurations could be used that fit within an aperture of mating geometric configuration. These and other mating mechanisms that ensure that the heating element is mounted within the tank in a desired configuration are possible and would fall within the scope of the present invention.

A cylindrical gasket 120 is coupled to the heating element flange 104 such that when the heating element 16 is coupled to the mounting device 100, the gasket 120 fits between the heating element flange 104 and the mounting flange 108. The gasket 120 includes a channel 124 that aligns with the channel 116 on the heating element flange 104 such that when coupled between the flanges, the channel 124 also receives the protrusion 112. A compression element, such as a clamp 128, is coupled to the outside of the mounting flange 108. The clamp 128 of the illustrated construction is a hose clamp, but it is understood that in other constructions, other types of clamps, including other mechanical clamps, and other types of compression elements can be used. When the heating element flange 104 and gasket 120 are coupled within the mounting flange 108, the clamp 128 is tightened by turning screw 132 to compress the gasket 120 between the flanges 104, 108, providing a water-tight seal between the heating element 16 and the tank 11.

The mounting devices discussed above can also be utilized to perform a method of installing a heating element in a water heater. The mounting device is coupled to a wall of the water tank 11, such as by welding, gluing, soldering, conventional fastening, or other known mechanical coupling methods. The heating element flange is then mated with the mounting flange, coupling the heating element 16 to the mounting device to ensure that the greatest cross-sectional area 26 is level with respect to the floor 25. Coupling the heating element flange to the mounting flange compresses the flanges to form a water-tight seal between them.

In the construction illustrated in FIGS. 1 and 4, coupling the flanges includes threading the heating element flange 28 into the mounting flange 30. Threading the flanges together also function to compress the O-ring 44 between the flanges, providing a water-tight seal between the flanges. To assist a person installing the heating element 16 in obtaining the desired level orientation of the heating element 16 within the tank 11, the method can also include aligning the identification mark (the arrow 64 in the illustrated embodiment) in the predetermined position to ensure the level orientation. It is understood that while in the illustrated construction the heating element 16 is manually installed, in other constructions the heating element can be automatically installed by a robot or other machinery. In such constructions, the identification mark would be aligned by the machine to ensure the desired orientation.

In the construction of FIGS. 10 and 11, coupling the flanges includes aligning the apertures 82, 84, and 94 of the heating element flange 74, the mounting flange 78, and the gasket 90 such that the gasket 90 fits between the heating element flange 74 and mounting flange 78. The fasteners 86 are then inserted through the apertures and are tightened to couple the heating element 16 to the tank 11. The tightening of the fasteners 86 compresses the gasket 90 between the flanges, providing a water-tight seal between the heating element 16 and the tank 11.

In the construction of FIG. 12, coupling the flanges includes placing the clamp 128 around the outside of the mounting flange 108, and placing the gasket 120 on the heating element flange 104 such that the channels 116, 124 are aligned. The channel 116 of the heating element flange 104 is then mated with the protrusion 112 of the mounting flange 108 and the heating element flange 104 is inserted into the mounting flange 108 with the gasket 120 therebetween. The clamp 128 is tightened down over the mated flanges, compressing the gasket 120 therebetween to form a water-tight seal between the heating element 16 and the tank 11.

The above-described methods and apparatus have been illustrated and described for use in a storage-type, electric water heater. However, it is understood that in other constructions, the methods and apparatus illustrated in FIGS. 1-12 could also be used in other types of fluid heating apparatus and still fall within the scope of the present invention. For example, the mounting device and method of mounting could be used in a commercial or industrial coffee maker, or any other fluid heating apparatus having a tank that holds fluid to be heated, and where the heating element is coupled to the tank such that the heating element is exposed to the fluid within the tank. Utilizing the mounting device and method of mounting in any similar fluid heating apparatus would assist in the installation of the heating element in the tank to ensure the desired level orientation of the heating element within the fluid tank.

Various other features and advantages of the invention are set forth in the following claims.

Claims

1. A water heater that rests in relation to the floor, the water heater comprising:

a water tank having a wall;

a mounting device coupled to the wall of the water tank; and

a heating element coupled to the mounting device, the heating element comprising a greatest cross-sectional area and cooperating with the mounting device such that coupling the heating element to the mounting device ensures the greatest cross-sectional area of the heating element is level with respect to the floor.

2. The water heater of claim 1, wherein the mounting device is threaded and the heating element includes mating threads.

3. The water heater of claim 2, wherein the threads on the mounting device and heating element comprise multi-start threads.

4. The water heater of claim 1, wherein at least one of the heating element and the wall of the tank includes an identification mark such that aligning the identification mark in a predetermined position results in the greatest cross-sectional area of the heating element being level with respect to the floor.

5. The water heater of claim 4, wherein the identification mark is located on the heating element.

6. The water heater of claim 4, wherein the identification mark comprises an arrow.

7. The water heater of claim 1, wherein the mounting device includes a mounting flange, and wherein the heating element includes a heating element flange that cooperates with the mounting flange.

8. The water heater of claim 7, further comprising a compression element placed over the cooperating mounting flange and heating element flange, the compression element compressing the flanges to form a water-tight seal between the mounting flange and heating element flange.

9. The water heater of claim 8, wherein the compression element comprises a clamp.

10. The water heater of claim 7, further comprising a resilient gasket placed between the cooperating mounting flange and heating element flange, wherein a compression element is coupled to the mating flanges, compressing the gasket therebetween to form a water-tight seal between the mounting flange and heating element flange.

11. The water heater of claim 10, wherein the compression element comprises a fastener.

12. A method of installing a heating element in a fluid heating apparatus, the fluid heating apparatus configured to rest in relation to the floor, the method comprising:

providing a fluid tank within the fluid heating apparatus, the fluid tank having a wall;

coupling a mounting device to the wall of the fluid tank, the mounting device configured to receive a heating element; and

coupling the heating element to the mounting device to ensure the greatest cross-sectional area of the heating element is level with respect to the floor.

13. The method of claim 12, wherein coupling the heating element to the mounting device includes threading the heating element into the mounting device.

14. The method of claim 13, wherein threading the heating element into the mounting device includes utilizing multi-lead threads.

15. The method of claim 12, wherein coupling the heating element to the mounting device includes coupling a heating element flange to a mounting flange.

16. The method of claim 15, wherein the heating element flange and the mounting flange are configured such that the flanges will only cooperate in a predetermined position to ensure that the greatest cross-sectional area of the heating element is level with respect to the floor.

17. The method of claim 15, further comprising compressing the heating element flange and mounting flange with a compression element to form a water-tight seal between the heating element flange and the mounting flange.

18. The method of claim 12, further comprising providing an identification mark on at least one of the heating element and the wall of the tank.

19. The method of claim 18, wherein coupling the heating element to the mounting device includes aligning the identification mark in a predetermined position such that the greatest cross-sectional area of the heating element is level with respect to the floor.

20. A method of mounting a heating element to a wall of a water tank in a water heater, the water heater configured to rest in relation to the floor, the method comprising:

coupling a mounting device to a wall of the water tank, the mounting device configured to receive a heating element;

aligning an identification mark on the heating element in a predetermined position; and

coupling the heating element to the mounting device such that the greatest cross-sectional area of the heating element is level with respect to the floor.

21. The method of claim 20, wherein coupling the heating element to the mounting device includes threading the heating element into the mounting device.

22. The method of claim 20, wherein coupling the heating element to the mounting device includes coupling a heating element flange to a mounting flange.

23. The method of claim 22, further comprising compressing the heating element flange and mounting flange with a compression element to form a water-tight seal between the heating element flange and the mounting flange.

24. A water heater configured to rest on the floor and having an axis substantially perpendicular to the floor, the water heater comprising:

a water tank having a wall;

a mounting device coupled to the wall of the water tank;

a heating element coupled to the mounting device, the heating element having a greatest cross-sectional area; and

a means for ensuring placement of the heating element within the water tank such that the greatest cross-sectional area of the heating element is substantially perpendicular to the axis.

25. The water heater of claim 24, wherein the means for ensuring placement comprises cooperating multi-start threads on the mounting device and the heating element and an identification mark on at least one of the wall of the water tank and the heating element.

26. The water heater of claim 24, wherein the means for ensuring placement comprises an identification mark on at least one of the wall of the water tank and the heating element such that aligning the identification mark in a predetermined position results in the greatest cross-sectional area of the heating element being perpendicular to the axis.

27. The water heater of claim 26, wherein the identification mark comprises an arrow.

28. The water heater of claim 24, wherein the means for ensuring placement comprises a mounting flange of the mounting device configured to receive a heating element flange of the heating element in only a predetermined position.

29. The water heater of claim 28, wherein the mounting flange and heating element flange are non-threaded, and wherein one of the mounting flange and heating element flange fits over the other of the mounting flange and heating element flange.

30. The water heater of claim 29, wherein one of the mounting flange and heating element flange includes a protrusion, and wherein the other of the mounting flange and heating element flange includes a recess configured to accept the protrusion such that the heating element is mounted to the tank wall in a position that results in the greatest cross-sectional area being substantially perpendicular to the axis.

31. The water heater of claim 29, further comprising a compression element placed over the mounting flange and heating element flange.

32. The water heater of claim 31, wherein the compression element comprises a clamp.

33. The water heater of claim 28, further comprising a resilient gasket placed between the cooperating mounting flange and heating element flange, wherein a compression element is coupled to the mating flanges, compressing the gasket therebetween to form a water-tight seal between the mounting flange and heating element flange.

34. The water heater of claim 24, further comprising a resilient gasket between the mounting device and heating element such that coupling the heating element to the mounting device compresses the gasket between the heating element and the mounting device to ensure a water-tight seal.