Abstract:
A water heater includes a water container, a combustion chamber having an opening that may be covered by a door and located adjacent the water container, a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, and a control valve for regulating fuel flow from an external fuel source. A fuel line extends between the control valve and the burner, the fuel line has a first substantially rigid portion connected to the control valve, a second interior portion extending from the door to the burner and a third flexible portion fixedly connected to both of the first and second portions.

Description:
TECHNICAL FIELD 
       [0001]    The technology in this disclosure relates to water heaters, particularly to water heaters that have door assemblies, such as those for water heater combustion chambers. 
       BACKGROUND 
       [0002]    Gas fired water heaters of the storage type traditionally have a water container placed above or adjacent to a combustion chamber and burner assembly. The burner assembly is controlled by a gas control valve which may be responsive to user input, such as a temperature setting. The burner assembly may have a main gas line extending from the gas control valve, through the combustion chamber wall or door, and to the burner. Gas lines have been constructed using various configurations and materials. By way of example, rigid tubing has been used where possible and in some cases threaded fittings are used to connect the rigid tubing to flexible tubing. 
         [0003]    It could be beneficial to provide a gas line that was simple, compact, durable, tamper-resistant and economical to construct. 
       SUMMARY 
       [0004]    We provide a water heater having a water container, a combustion chamber adjacent the water container, the combustion chamber having an opening that may be covered by a door. The water heater has a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container and a control valve for regulating fuel flow from an external fuel source. A fuel line extends between the control valve and the burner. The fuel line has a first substantially rigid portion connected to the control valve, a second interior portion extending from the door to the burner and a third flexible portion fixedly connected to both of the first and second portions. 
         [0005]    We also provide a water heater having a water container and a combustion chamber having an opening that may be covered by a door and located adjacent the water container. The water heater also has a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container and a fuel control valve associated with the burner and adapted to control the flow of fuel to the burner for combustion. A fuel line extends between the fuel control valve and the burner. The fuel line has a first tubular substantially rigid portion located adjacent to and fluidly connected with the control valve, a second tubular substantially rigid portion located adjacent to and fluidly connected to the burner and a flexible portion brazed to each of the first and second tubular substantially rigid portions and fluidly connecting the first and second tubular substantially rigid portions. The fuel line fluidly connects the fluid control valve and the burner. 
         [0006]    We further provide a fuel line for a combustion water heater. The water heater associated with the fuel line has a fuel control valve, a combustion chamber defined at least in part by an opening that may be covered by a door and a burner located within the combustion chamber. The fuel line has a first tubular substantially rigid portion extending from and fluidly connected to the fuel control valve. The fuel line also has a second tubular substantially rigid portion having a first end fluidly connected to and extending from the burner and a second end located adjacent to the combustion chamber wall. The fuel line also has a flexible portion having a first end fixedly connected to and fluidly connected with the first tubular substantially rigid portion and a second end fixedly connected to and fluidly connected with the second end of the second tubular substantially rigid portion such that the fuel line provides a fluid connection between the fuel control valve and the burner. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a schematic front elevational view of a water heater. 
           [0008]      FIG. 2  is a schematic side view of the water heater of  FIG. 1 . 
           [0009]      FIG. 3  is a perspective view of the lower portion of a water heater of the type shown in  FIGS. 1 and 2 . 
           [0010]      FIG. 4  is a front elevational view of a fuel line assembly of a water heater of the type shown in  FIGS. 1 and 2 . 
           [0011]      FIG. 5  is a side elevational view of the fuel line assembly of  FIG. 4 . 
           [0012]      FIG. 6  is top plan view of the fuel line assembly shown in  FIGS. 4 and 5 . 
           [0013]      FIG. 7  is a perspective view of a partially assembled fuel line and burner mount for a water heater. 
           [0014]      FIG. 8  is a perspective view of the fuel line and burner mount for a water heater in a further assembled state. 
           [0015]      FIG. 9  is a perspective view of a flange for a water heater fuel line. 
           [0016]      FIG. 10  is a perspective view of a flange for a water heater fuel line with a portion of the fuel line inserted therein. 
           [0017]      FIG. 11  is a perspective interior view of the fuel line assembly of  FIG. 4 . 
           [0018]      FIG. 12  is a perspective view of the fuel line assembly of  FIGS. 4 and 5 . 
           [0019]      FIG. 13  is an exploded perspective view of a portion of the fuel line assembly of  FIGS. 3 and 5 . 
           [0020]      FIG. 14  is a perspective view of a water heater door of the type shown in  FIG. 13 . 
           [0021]      FIG. 15  is a partial cross-sectional view of the water heater door shown in  FIG. 14 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    It will be appreciated that the following description is intended to refer to specific aspects of the representative structures selected for illustration in the drawings and is not intended to define or limit the technology of this disclosure, other than in the appended claims. 
         [0023]    Turning now to the drawings in general and  FIGS. 1-3  in particular, the number “2” designates a storage type gas water heater  2 . Water heater  2  includes jacket  4  which surrounds a water tank  6 , a main burner  14  in a combustion chamber  15 . Passing through the center of the tank  6  is a flue  10 , in this instance incorporating a series of baffles  12  to better transfer heat generated by the main burner  14 . Water tank  6  is preferably of mains pressure capability and is capable of holding heated water. Water tank  6  is preferably insulated by foam insulation  8 . Alternative insulation may include fiberglass or other types of fibrous insulation, heating retaining material and the like. Fiberglass insulation  9  surrounds combustion chamber  15  and the lowermost portion of water tank  6 . It is possible that heat resistant foam insulation can be used if desired. A foam dam  7  separates foam insulation  8  and fiberglass insulation  9 . 
         [0024]    Located underneath the water tank  6 , within the combustion chamber  15 , is the main burner  14  which uses any type of fuel such as oil, natural gas or other gases such as LPG, for example. Other suitable fuels may be substituted. Fuel is provided to the main burner  14  through the main fuel line  20 , which is fluidly connected to fuel control valve  21 . Fuel control valve  21  supplies fuel to burner  14  by way of main fuel line  20 . Main burner  14  combusts a fuel and air mixture wherein combustion air is drawn into combustion chambers through openings  27 . The resulting hot products of combustion rise up through flue  10 , possibly with heated air. Water tank  6  is lined with a glass or other type of coating for corrosion resistance. Bottom  5  of water tank  6  is preferably coated on both its interior facing surface  3  and exterior facing surface  11 . The thickness of the coating of exterior facing surface  11  may be about half of the thickness of interior facing surface  3 . Also, the lower portion of flue  10  is preferably coated on both of its opposing surfaces. The surface exposed to the flue gases has a thickness about half the thickness of the surface exposed to water in water tank  6 . It has been discovered that the glass coating helps to prevent scaling of the flue and water tank surfaces. 
         [0025]    Combustion chamber  15  also contains a pilot burner  49  connected to fuel control valve  21  by pilot fuel supply line  47 . A sheath  52 , preferably made of copper, containing wires (not shown) from a flame detecting thermocouple  51  to ensure that in the absence of a flame at pilot burner  49  fuel control valve  21  shuts off the gas supply. Thermocouple  51  may be selected from those known in the art. RobertShaw Model No. TS 750U is preferred. 
         [0026]      FIGS. 4-6  particularly show main fuel line  20  and pilot fuel supply line  47  extending outwardly from a covering or door  25 , which provides access to the combustion chamber  15  through opening  110 . Door  25  is removably sealable to skirt  60  that forms the side wall of combustion chamber  15  at opening  110 . Door  25  is held into position by a pair of screws  62  or by any other suitable means. Pilot fuel supply line  47  and fuel supply line  20  pass through door  25  in a substantially fixed and sealed condition. Sheath  52  also extends through door  25  in a substantially fixed and sealed condition as does igniter line  64 . Igniter line  64  connects on one end to an igniter button  22  and a piezo igniter  66  (see  FIG. 5 ). Igniter button  22  can be obtained from Channel Products, for example. Each of pilot fuel supply line  47 , fuel supply line  20  and sheath  52  are removably connectable to fuel control valve  21  by compression nuts  68 ,  70  and  72 , respectively. Each of compression nut  68 ,  70  and  72  are threaded and threadingly engage control valve  21 . 
         [0027]    The products of combustion pass upwardly and out the top of jacket  4  via flue outlet  16  after heat has been transferred from the products of combustion. The flue outlet  16  discharges conventionally into a draft diverter  17  which in turn connects to an exhaust duct leading outdoors. 
         [0028]    Water heater  2  is preferably mounted on leg  24  to raise bottom pan  26  off the floor. Bottom pan  26  preferably has one or more openings  27  or some other means (not shown) for receiving combustion air. Where bottom pan  26  meets jacket  4 , the mating surfaces (made up from surfaces of bottom pan  26  and jacket  4 ) can be sealed thoroughly to prevent ingress of air or any flammable gas or vapor. The cylindrical wall of jacket  4  (the majority of gas water heaters are cylindrical; however, a cubic or other shaped jacket  4  may be utilized) can be sealed substantially gas tightly so no openings or breaks remain upon assembly and installation. 
         [0029]    In particular, gas, water, electrical, control, or other connections, fittings or plumbing, wherever they pass through the jacket  4  or bottom pan  26 , can be sealed airtight. The joining area of bottom pan  26  to jacket  4  and all service entries or exits to the jacket  4  need not be sealed airtight. It is preferred, however, that the space around burner  14  be substantially air/gas tight except for means to supply combustion air. 
         [0030]    Referring now to  FIGS. 4-8 , a main fuel line  20  for a water heater  2  is shown.  FIGS. 5 and 6  show the main fuel line  20  in connection with a pilot  49  and pilot fuel line  47 .  FIGS. 7 and 8  show the main fuel line  20  in connection with a mounting portion, such as a flange  74 , for mounting the main fuel line  20  to the door  25 . The fuel line  20  has a substantially rigid tubular portion  76  located outside of the combustion chamber  15 . The substantially rigid tubular portion  76  is adapted to extend downwardly from the control valve  21 . The substantially rigid tubular portion  76  is preferably constructed of cold-rolled steel, or a similar material, which provides an economical and strong tube. The substantially rigid tubular portion  76  is connected to the fuel control valve  21  using a compression fitting  70 , including a flared portion  78  and a threaded coupling  80 . The flared portion  78  may have an inverted double-wall flare, which more readily conforms to the valve seat (not shown) on the fuel control valve  21 , providing a strong seal and allowing simpler manufacturing due to the lower tolerances required. A fiber gasket (not shown) is optionally used with the compression fitting to further seal the main fuel line  20  to the fuel control valve  21 . 
         [0031]    A flexible portion  82  is fixedly connected to the opposite end of the substantially rigid tubular portion  76  from the fuel control valve  21  at a joint  84 . The fixed connection refers to a permanent, non removable connection, such as brazing, welding, soldering, crimping or adhering. The precise mechanism of the permanent connection is unimportant so long as it provides sufficient gas tightness, heat resistance and non-removability. The brazed joint  84  replaces traditional (non-fixed) attachment means, such as compression fittings or unions, which are removable and non-permanent. The fixed connection of the brazed joint  84  helps to make the assembly tamper resistant and decreases the need for maintenance. 
         [0032]    A second substantially rigid tubular portion, or internal fuel delivery tube  86 , extends inwardly from the door  25  to the burner  14 . The internal fuel delivery tube  86  is fixedly connected at a joint  88  to the flexible portion  82  to provide a passageway from the fuel control valve  21  to the burner  14 . Like the joint  84 , joint  88  may be brazed. Providing the brazed joint  88  adjacent the door  25  allows for the use of less rigid material than traditional threaded engagements allows the main fuel line  20  to be positioned close to the jacket  4  of the water heater  2 , allowing the production of a more compact product. 
         [0033]    Referring now to  FIGS. 7 and 8 , the main fuel line  20  may have a mounting tab  92  located at an opposing end of the internal fuel delivery tube  86  from the door  25 . The mounting tab may be brazed to the main fuel line and is adapted to engage a recess or post (not shown) within the combustion chamber  15  for support of the internal fuel delivery tube  86  and burner  14 . The burner  14  is mounted on a burner bracket  90 , which is brazed to the internal fuel delivery tube  86 . 
         [0034]    Referring now to  FIGS. 9-12 , the mounting flange  74  may be either stamped or machined metal, such as a cold-rolled steel. The flange  74  has a flat, disc shaped portion  96  and a ring shaped central portion  98  which defines a passageway in the center of the disc shaped portion  96 . The flange  74  is preferably connected to the door  25  using rivets which pass through rivet holes  100 , or may be connected by some other attachment means. Prior to brazing the flexible portion  82  to the internal fuel delivery tube  86 , the flange  74  is positioned around the internal fuel delivery tube  86  and attached thereto by crimps  102  on the ring shaped portion  98 . An optional gasket (not shown) may be used to further seal the flange  74  to the main fuel line  20 . 
         [0035]    Once the main fuel line  20 , along with the flange  74  and mounting tab  92  have been brazed together and leak checked, the entire assembly may be zinc plated to aid corrosion resistance. 
         [0036]    Eliminating the larger traditional couplings in favor of brazed joints  84 ,  88  allows the use of less material in construction. Further, overall material costs are reduced as only a relatively small portion of expensive flexible tubing is used. 
         [0037]    Referring now to  FIGS. 13-15 , like the door  25  discussed above, a door  125  may also be used. The door  125  has a port  126  extending therethrough and sized to accommodate the main fuel line  20 . Unlike the door  25 , which is fixed to the main fuel line  20  by means of a flange  74 , the mounting portion that secures the main fuel line  20  within the port  126  is a collar  128  which extends outwardly from the door  125 . The collar  128  is crimped to the main fuel line  20  at a number of crimp points  130 . The collar  128  is of unitary construction with the door  125  and is formed by punching out a hole in the door  125  and pressing the material around the hole into a tubular form. 
         [0038]    The size and shape of the various portions can be increased or decreased to suit the application and/or size and/or shape of the water heater. The location of the various conduits relative to the water heater may also be varied depending on the size, shape and location of the water heater. Conversely, the upper portion of the water heater may be the upper half of the water heater, but may be a larger portion so long as the combustion air opening is above the dilution air intake. 
         [0039]    It will be understood that water heater  2  may be constructed with a wide variety of materials, in a wide variety of shapes and sizes. For example, any number of types of burners  14  may be employed, along with various types of fuel control valves  21  and the like. Also, various types of insulation, water containers/tanks and jackets may be employed. 
         [0040]    Although the technology of this disclosure has been described in connection with specific representative forms thereof, it will be appreciated that a wide variety of equivalents may be substituted for the specified elements described herein without departing from the spirit and scope of this technology as described in the appended claims.