An apparatus is provided for supporting an expansion tank and, more particularly, a bracket is provided for attachment between an expansion tank and an associated hot water heater or adjacent structure.
Expansion tanks are used in domestic water systems particularly to protect hydronic or thermal (hot water) heating systems. An expansion tank is required when the water system includes a backflow prevention device such as a check valve, a pressure reducing valve, or other means of reduced pressure backflow protection. The tank is a manufactured cylindrical vessel normally possessing slightly rounded ends and typically made of steel or other rigid material, which conventionally may be rated to take an internal pressure of up to 200 pounds per square inch (psi). The expansion may be provided with a pipe nipple usually at the center of one end for connection to the plumbing, thereby permitting water and any entrained air to enter and exit the tank. The expansion tank houses an internal expandable rubber bladder to separate the water from a cushion of pressurized air within the tank. An air valve often placed at the opposite end of the tank permits a plumber or installer to adjust the air pressure behind the bladder to correspond as needed to the normal system water pressure. In the absence of the air valve, a predetermined back pressure is applied to the bladder during manufacture.
Thermal expansion tanks extend the life of water heaters and similar equipment. Expansion tanks may also be used to eliminate the phenomenon known in the trade as “water hammer”, caused when a plumbing system vibrates and emits loud knocking noises due to water surging against trapped air pockets in the piping. They may heat and cool periodically and may change weight by virtue of the varying contents during intermittent usage. Because the tank partially fills with water during use, a typical tank used in the home may weigh up to ten pounds or more. In commercial installations, an expansion tank may weigh up to 20 pounds or more during use.
Expansion tanks may be installed in either a vertical, horizontal or occasionally other orientation. Since expansion tanks can fail over time and may need to be changed periodically, or the connections to the tank may need to be replaced, a simple and quick means of access and replacement is desired.
The expansion tank, as well as the piping to which the tank is connected, may expand and contract very slightly with temperature changes. Means for supporting the tank must allow for such very slight expansion and contraction without permitting major disruptive movement. Vibration should also be minimized as it could be deleterious to the piping system leading to premature failure. Vertically mounted tanks should be well secured to prevent tipping as the internal weight changes.
According to manufacturers' instructions and official plumbing requirements, a thermal expansion tank must have an external means of support other than the piping. This is particularly necessary when piping other than hard metal piping is used. Currently there are no known official standard prescribed ways of furnishing such means. As commercial piping itself has evolved over time from hard metal piping to more modern, less expensive systems utilizing flexible plastic piping, the means of support for the expansion tank becomes even more critical to prevent the tank from moving significantly, tilting, twisting or becoming disconnected during use due to flexing of the piping and filling and emptying of the tank as well as possible disruptions in the surrounding area. Custom arrangements whereby hard piping must unavoidably be used to support the tank in the vicinity of the water heater, followed by flexible plastic piping elsewhere in the system, become more expensive, time-consuming and cumbersome to install.
Some custom support means currently employed in the art for expansion tanks include use of various types of metal or plastic strapping to joists, rafters, columns, studs, pipes, posts, or similar structural means within the building structure, wiring the tank to such structural means, cradling the tank between parallel or other pieces of lumber or similar support means that are custom-installed on site, building a shelf under the expansion tank, and similar miscellaneous means that may vary with the job situation and the individual experiences of the plumber or installer. All such custom on-site installation methods are time-consuming and therefore costly, can change with conditions encountered on the individual job and location where the tank is being placed, and may not pass official inspection.
Plumbing codes prevent use of support means that would violate the integrity of the manufactured tank itself such as welding or brazing a piece of metal to the tank, fastening a bracket to the tank by means of screws or fasteners that would penetrate the wall of the tank, or similar such means that may lead to tank failure and subsequent safety hazard or damage to the surroundings. Since the tank is usually coated with a surface protection means such as paint to prevent external corrosion, thereby extending the life of the tank, it is undesirable to employ a support means that would damage that surface protection.
Adhesive means such as gluing or duct-taping the tank to a building structural member or other point are generally impractical and would not survive over an extended period of time, due to repeated weight changes plus slight expansion and contraction with thermal changes of the tank as well as aging of the adhesive means, nor pass official inspection.
Finally, tanks that are installed on a nearby wall or other surrounding structure should have some sort of separate overflow or rupture protection to protect the surroundings against flooding should failure occur, often mandated by inspectors, architects or official code. Tanks installed on the water heater itself can benefit from use of the same drainage tray typically used on the floor under water heaters and increasingly required in modern installations, including where such heaters are installed on upper floors or in water-sensitive areas of a building. Similarly, any alarm system installed to warn of failure of the water heater could also detect any problem with the expansion tank, rather than needing a second system.
For the foregoing reasons there is a need for a simple, compact and inexpensive apparatus to affix a thermal expansion tank directly to a moveable free-standing structure, such as a residential, commercial or industrial hot water heater. The expansion tank may be installed above the heater in a vertical, horizontal, or other orientation such that any means that has been installed to protect the surroundings from flooding and water damage due to failure of the heater, such as an overflow drainage tray installed under the heater or a flood alarm system, can simultaneously protect against any failure of the expansion tank without requiring separate flooding protection as would be needed for tanks located remotely from the water heater, including those mounted on a nearby building structural member. The apparatus for affixing the expansion tank should simplify and require minimal use of time to install the apparatus, minimize the space required for the apparatus, not damage the integrity or surface coating of the tank while making it integral to the hot water heater, minimize the length of piping attaching the tank to the heater, and meet all official plumbing requirements for installation of such a tank. Since the expansion tank will change weight during use, the apparatus should permit the tank to change weight or expand and contract slightly in normal repetitive usage without detaching itself from the apparatus holding it, or causing other damage to the plumbing system or the surroundings. Stress and strain on the piping system connected to the tank should also be minimized by not forcing the piping to bear the weight of the tank and its contents, thereby allowing the use of modern flexible plastic piping if desired rather than metal piping which is more expensive and more difficult to assemble, and to prevent said piping from detaching itself from the tank or suffering breakage or leakage due to such stress and strain. Finally, the new supporting apparatus should allow the tank to be easily removed from such apparatus for replacement when the tank fails or is due to fail because of age or continued use, and to easily reinstall a replacement tank without unnecessary dismantlement of the supporting apparatus or time-consuming cleanup or refurbishing of the apparatus.
An apparatus is provided for supporting a thermal or hydronic expansion tank relative to a hot water heater. The tank includes a pipe nipple for fluid connection to a water piping system. The tank supporting apparatus comprises a rigid bracket adapted to be secured to the tank and to the hot water heater. The bracket providing support for the tank adjacent to the pipe nipple. Means interconnecting the tank and the bracket for securing the tank to the bracket.
In one aspect, the bracket comprises a base, and an end wall at each end of the base. The end walls are adapted for engaging and supporting the tank, wherein one of the end walls engages the tank adjacent the pipe nipple and the other of the end walls engages the tank past the midpoint of the length of the tank from the base.
For a more complete understanding of the apparatus for supporting an expansion tank, reference should now be had to the embodiments shown in the accompanying drawings and described below. In the drawings:
Certain terminology is used herein for convenience only and is not to be taken as a limiting. For example, words such as “upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,” “downward,” “top” and “bottom” merely describe the configurations shown in the FIGs. Indeed, the components may be oriented in any direction and the terminology, therefore, should be understood as encompassing such variations unless specified otherwise. The words “interior” and “exterior” refer to directions toward and away from, respectively, the geometric center of the core and designated parts thereof. The terminology includes the words specifically mentioned above, derivatives thereof and words of similar import.
A supporting apparatus for an expansion tank is described herein and comprises a universal bracket member suitable for supporting the thermal expansion tank in compliance with the requirements of official plumbing codes and inspections. The supporting apparatus meets all of the objectives listed above and eliminates the need to custom-construct a support means on site for each individual situation or mandating that the tank be fastened to a wall or other remote fixed building structural element with no alternative option. It is understood, however, that the supporting apparatus does not preclude such remote mounting possibility should a particular individual circumstance such as a space restriction prevent the thermal expansion tank from being directly mounted on the hot water heater.
Referring now to the drawings, wherein like reference numerals designate corresponding or similar elements throughout the several views,
One embodiment of the supporting apparatus is shown in
Surface A of the bracket is a base support surface containing holes 7 through which the bracket may be fastened directly to the top or side of a hot water heater or other free-standing structure. Alternatively, if desired, the bracket may be fixed to a building structural member by use of standard fastener means such as screws, bolts, nails or the like. Surface B extends from one end of Surface A at right angles to it for supporting the front end of an expansion tank. Surface C is located at the other end of Surface A and also extends at right angles to Surface A for supporting the rear end of the expansion tank.
Surfaces D and E are optional sidewalls extending at right angles to Surface A and perpendicular to Surfaces B and C. Preferably, the sidewalls are sufficiently distant from the expansion tank to permit insulation to be wrapped or sprayed around the tank. The sidewalls may contain slots or holes 8 through which a flexible securing means, as more fully described hereinafter, is disposed and subsequently fastened about the expansion tank to secure it to the bracket.
As shown in
In yet another embodiment of the support means as shown in
Optionally one or more ends of securing means 12 may be pre-attached to Surface A or other point on the bracket during manufacture by means comprising one or more rivets, adhesive, spot welding, crimping, stitching or other similar means commonly known to the art, to allow rapid installation of the entire assembly without needing to separately manipulate said securing means 12 on site as loose individual component(s) during such installation, with only its(their) free end(s) subsequently needing to be fastened with a clip, clamp or other means known to the art either to the opposite side of the bracket, or to each other if securing means 12 is composed of two components, as that particular manufactured version of the bracket dictates. An example of such pre-attached securing means is shown in
In another embodiment shown in
In another alternative (not shown), Surfaces B and C may also be prepared as end plates that extend well beyond the centerline of the tank and contain holes or slots through which the pipe nipple 3 and air valve 4, respectively, can simultaneously extend. In this case, while Surface B remains rigid, Surface C has been manufactured to be slightly flexible, having sufficient spring tension to spring back into place after being temporarily bent. During installation, after the bracket has been affixed to the supporting surface, pipe nipple 3 is placed through hole 9 in Surface B while Surface C is bent away slightly to allow clearance for air valve 4, thus permitting the tank to enter the bracket. Upon release, Surface C returns to its normal position.
Still another optional example of the support means is shown in
A preferred embodiment of the support means in actual use is demonstrated in the three views of
As previously mentioned in the discussion of
In yet a further manifestation of the support means, a prototype bracket was prepared by slicing lengthwise a piece of rigid PVC (polyvinyl chloride) pipe to produce a curved section amounting to half the pipe diameter or less. In this first prototype the curved section did not necessarily mate exactly with the periphery of the expansion tank, but merely touched the tank surface with its longitudinal edges. Holes were drilled in positions at or near the center of the section's longitudinal axis to permit it to be secured to a fixed support such as the outer skin of a water heater, or if necessary to a building structural member, with standard fastener means such as screws, nails, bolts or the like. Flexible securing means were run around the outer periphery of the bracket before tightening it to the fixed support, and subsequently fastened around the expansion tank to secure it to the bracket. Alternatively, one or more additional slots or holes could be made a short distance from the edges of the bracket, to permit threading of one or more flexible securing means through these openings and subsequently fastened about the expansion tank to secure it to the bracket.
In another embodiment of the support means,
In another version of the bracket, the first curved PVC surface 30 described in
These manually fabricated examples demonstrated that other plastic versions of the support means could also be produced either by the means illustrated above or by more sophisticated industrial methods commonly known to the art including injection or compression molding and other methods, to yield a similar rigid or semirigid plastic bracket in a single manufacturing step without the need to cement together separate components. Other plastic materials such as PVC, polypropylene, nylon, ABS (acrylonitrile-butadiene-styrene), fiberglass-filled plastics, or other rigid or semi-flexible plastics could be used. Alternatively, the assembly could be made either wholly or partially of metal or other rigid or semirigid material.
As an option, the surfaces of either 14a or 14b could be fastened to each other by a central bolt or other single point of contact, whereby the first curved surface 30 component could be oriented in a vertical, horizontal, or any angled direction relative to the second curved surface 38 according to the needs of the installation and then locked in position by tightening the bolt, securing the bolt with nuts, use of a second bolt or screw, or other means known to the art.
In a further variation of the means described above in the descriptions for
Optionally a hole or depression 48 may be provided in the base 43 to engage means to prevent subsequent dislodging of the second component 30 out of the first. Such means could include a spring-loaded detent, a spring-loaded ball, an integral spring created by a deforming some portion of sliding base 46 near its end, or other means commonly known to the art. An opposite arrangement could alternatively be used, where the hole or depression is located in the second component and the anti-dislodging means in the first, to preclude the bracket from involuntarily exiting the slot once in place. Alternately, simple means such as a screw driven through both of the pieces, or other such means may be employed.
As stated before in the discussion of
Although the present supporting apparatus for an expansion tank has been shown and described in considerable detail with respect to only a few exemplary embodiments thereof, it should be understood by those skilled in the art that we do not intend to limit the apparatus to the embodiments since various modifications, omissions and additions may be made to the disclosed embodiments without materially departing from the novel teachings and advantages, particularly in light of the foregoing teachings. Accordingly, we intend to cover all such modifications, omission, additions and equivalents as may be included within the spirit and scope of the supporting apparatus as defined by the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures.
This application is related to U.S. provisional application Nos. 62/291,630, filed Feb. 5, 2016, and 62/455,089, filed Feb. 6, 2017, entitled “BRACKET FOR EXPANSION TANK”, naming James T. Bober as the inventor. The contents of the provisional applications are incorporated herein by reference in their entirety, and the benefit of the filing dates of the provisional applications is hereby claimed for all purposes that are legally served by such claim for the benefit of the filing date.
Number | Date | Country | |
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62291630 | Feb 2016 | US | |
62455089 | Feb 2017 | US |