Patent Publication Number: US-11662121-B2

Title: Modular linear fireplace system, assemblies and methods

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 16/439,668, titled “Modular Linear Fireplace System, Assemblies and Methods,” filed Jun. 12, 2019, which is a continuation of U.S. application Ser. No. 14/639,935, titled “Modular Linear Fireplace System, Assemblies and Methods,” filed Mar. 5, 2015, which claims the benefit of and priority to U.S. Provisional Application No. 61/949,208, titled “Modular Linear Fireplace System, Assemblies and Methods,” filed Mar. 6, 2014, which are incorporated herein in their entireties by reference thereto. 
    
    
     TECHNICAL FIELD 
     Embodiments of the present invention are directed to fireplace assemblies, and more particularly, to gas-burning, linear fireplaces. 
     BACKGROUND 
     Gas-burning, linear fireplaces have become very popular as decorative signature pieces in homes, buildings, and the like. Large linear fireplaces are typically custom-built or semi-custom-built for a designated space. Large custom linear fireplaces are often very expensive to build and to install. The large custom linear fireplaces are usually fully built off-site, and installation of the fireplaces often requires partial removal of walls or other building structures to allow the fireplaces to be moved as a single unit to the installation site and into position for installation in the designated room. This fireplace installation process can be extremely expensive, time-consuming, and labor-intensive. 
     Conventional linear fireplace assemblies are also constructed in a manner that, during operation of the fireplace, the external surfaces of the fireplace can reach temperatures that far exceed 172° F. As a result, the installation requirements for the linear fireplaces prohibit the use of combustible building materials against or immediately adjacent to the fireplace. This restriction to only non-combustible materials surrounding the fireplace can significantly add to the fireplace installation costs and limit the choice of decorative materials used in the room that houses the linear fireplace. 
     SUMMARY 
     The present invention is directed to a linear fireplace system, assemblies, modular units, and related methods that can be installed in a modular fashion at a selected installation location so as to avoid drawbacks experienced in the prior art. In at least one embodiment, the system includes modular linear units, corner units, and/or end units that can be interconnected to form a modular linear fireplace assembly. The system can include an alignment track system with a track member that receives alignment rails on the bottom of the modular units to axially align the interconnected units. The system can include a combustion air flow passage within the fireplace that maintains a relatively low exterior temperature of the assembly and that allows combustible and non-combustible building materials to be installed against or immediately adjacent to the top and base portions of the modular units of the assembly. 
     Another embodiment provides a modular linear fireplace system comprising a plurality of linear fireplace units each having opposing first attachment end portions with configurations common to the linear fireplace units, wherein the linear fireplace units are interchangeable. Each fireplace unit has a base portion and a top portion spaced apart from the base portion to define a firebox therebetween in which combustion of a fuel gas occurs during use. The base portion has a gas line and a burner assembly operatively connected to the gas line. The burner assembly is positioned adjacent to a bottom portion of the firebox. The firebox has open lateral end portions adjacent to the first attachment end portions, wherein each linear fireplace unit is interchangeably securable to a second one of the linear fireplace units at one of the first attachment end portions to form joined linear fireplace units and to provide a continuous elongate firebox area through the joined linear fireplace units. The system has a plurality of end units each having second attachment end portions with common configurations that mate with the first attachment end portions of any one of the linear fireplace units. Each end unit is interchangeably connectable to a selected one of the linear fireplace units to close one of the open lateral end portions of the firebox of the any one of the linear fireplace units. 
     Another embodiment provides a modular linear fireplace assembly comprising first and second modular linear fireplace units each having opposing first and second attachment end portions with common configurations, wherein the linear fireplace units are interchangeable with each other. Each fireplace unit has a base portion and a top portion spaced apart from the base portion to define a firebox therebetween in which combustion of a fuel gas occurs during use. The base portion has a gas line and a burner assembly operatively connected to the gas line, and the burner assembly is positioned adjacent to a bottom portion of the firebox. The firebox has open lateral end portions adjacent to the first and second attachment end portions. A first modular end unit has at least a first end portion connected to the first attachment end portion of the first modular linear fireplace unit and positioned to close the open lateral end portion of the firebox of the first modular linear fireplace unit. The first end portion of the first modular end unit has a common configuration so as to be interchangeably attachable to the first attachment end portion of the second modular linear fireplace unit. A second modular end unit has at least a second end portion connected to the second attachment end portion of the second modular linear fireplace unit and positioned to close the open lateral end portion of the firebox of the second modular linear fireplace unit. The second end portion of the second modular end unit has a common configuration so as to be interchangeably attachable to the second attachment end portion of the first modular linear fireplace unit. The first and second modular linear fireplace units are coupled together to provide a continuous elongate firebox area therethrough. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an isometric view of a multi-segment, modular linear fireplace assembly of one embodiment of the modular, linear fireplace system in accordance with an embodiment of the present technology. 
         FIG.  2    is an isometric view of modular units of the system of  FIG.  1    arranged in a linear fireplace assembly with an L-shaped, see-through configuration. 
         FIG.  3    is an isometric view of modular units of the system of  FIG.  1    arranged in linear fireplace assembly with an L-shaped, single-side configuration. 
         FIG.  4    is an isometric view of modular units of the system of  FIG.  1    arranged in a linear fireplace assembly having a straight, see-through configuration with a see-through end cap on one end and a closure end panel on the opposite end. 
         FIG.  5    is an isometric view of modular units of the system of  FIG.  1    arranged in a linear fireplace assembly having a straight, single-side configuration with closed end panels. 
         FIG.  6 A  is an isometric view of a modular linear fireplace unit of the system of  FIG.  1   , wherein the unit is shown in a see-through configuration. 
         FIG.  6 B  is a partially cutaway and partially exploded isometric view of two modular units of an embodiment arranged in a straight line configuration and showing a torsion bar assembly of spanning between the two units. 
         FIG.  7    is an isometric view of a modular linear fireplace unit of the system of  FIG.  1   , wherein the unit is shown in a single-side configuration. 
         FIGS.  8 A and  8 B  are front and rear isometric views of a corner unit of the system of  FIG.  1   , wherein the corner unit is shown in a see-through configuration. 
         FIG.  9    is an isometric view of another corner unit of the system of  FIG.  1   , wherein the corner unit is shown in a single-side configuration. 
         FIG.  10    is an isometric view of a see-through end cap unit of the system of  FIG.  1   . 
         FIG.  11 A  is an isometric view of a single-side end cap unit of the system of  FIG.  1   . 
         FIG.  11 B  is an isometric view of a panel end closure of the system of  FIG.  1   . 
         FIG.  12    is a bottom isometric view of the modular linear fireplace assembly of  FIG.  4    showing an installation alignment system on the bottom of the modular units. 
         FIG.  13    is a top isometric view of an installation track member shown removed from the assembly of  FIG.  12   . 
         FIG.  14    is a bottom isometric view of the modular linear fireplace assembly  FIG.  12    with the installation track member removed and showing the alignment rails on the base portions of the modular fireplace units. 
         FIG.  15    is a cross-sectional view taken substantially along lines  15 - 15  of  FIG.  14    showing the interface between the installation track member and the alignment rails on the bottom of the modular fireplace units. 
         FIG.  16    is a bottom isometric view of the modular linear fireplace assembly of  FIG.  3    with the installation track removed to show the alignment rail configuration on the bottom of the modular fireplace units. 
         FIG.  17    is a cross-sectional isometric view taken substantially along line  17 - 17  of the modular fireplace unit of  FIG.  6   . 
         FIG.  18    is a top isometric view of a base portion of the modular fireplace unit of  FIG.  6   . 
         FIG.  19 A  is a bottom isometric view of a top portion of the modular fireplace unit of  FIG.  6   . 
         FIG.  19 B  is a cross-sectional view taken substantially along lines  19 B- 19 B of  FIG.  19 A . 
         FIG.  20 A  is the cross-sectional isometric view of  FIG.  17    illustrating the combustion air intake flow path through the modular fireplace unit to the combustion chamber. 
         FIG.  20 B  is a cross-sectional isometric view taken substantially along lines  20 B- 20 B of the modular fireplace unit of  FIG.  6    illustrating the exhaust flow path from the combustion chamber out the exhaust flue. 
         FIG.  21    is an isometric view of a modular fireplace unit in a shipping configuration with supportive, removable shipping brackets installed. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure describes a modular, linear gas-burning fireplace system, assemblies, and related components in accordance with embodiments of the present technology. Several specific details of the invention are set forth in the following description and the Figures to provide a thorough understanding of certain embodiments of the technology. One skilled in the art, however, will understand that the present technology may have additional embodiments, and that other embodiments of the technology may be practiced without several of the specific features described below. 
       FIG.  1    is an isometric view of a multi-unit, modular linear fireplace assembly  10  in one embodiment of the modular linear fireplace system  12  in accordance with an embodiment of the present technology. The illustrated modular linear fireplace assembly  10  is shown with a plurality of modular units  14  arranged in a straight-line, single-side configuration in an installation that includes non-combustible finish materials  16  and combustible finish building materials  17  mounted on or immediately adjacent to the fireplace assembly  10 . The illustrated modular linear fireplace assembly  10  is a multi-segmented, direct vent gas-burning fireplace configured to burn natural gas, propane or other selected fuel gas within an elongated firebox  18 . 
     The system  12  includes a plurality of modular units  14  of different configurations that can be interconnected in a wide variety of arrangements to achieve very aesthetically pleasing linear fireplace installations of different sizes or dimensions while avoiding the significant drawbacks experienced by conventional large customized linear fireplace installations.  FIG.  2    is an isometric view of an L-shaped assembly  2  having modular, see-through linear fireplace units  20  connected to a see-through corner unit  22 , a see-through end cap  24 , and an end closure panel  26   a , which are discussed in greater detail below.  FIG.  3    is an isometric view of an L-shaped assembly  3  having modular “single-side” (i.e., a single viewing side and not fully see-through) linear fireplace units  28  with different lengths connected to a single-side corner unit  30  and single-side end closure panels  26   b .  FIG.  4    is an isometric view of a straight-line assembly  4  having see-through linear fireplace units  20  connected to a see-through end cap  24  and a single-side end closure panel  26   a .  FIG.  5    is an isometric view of a straight-line assembly  5  having single-side linear fireplace units  28  of different lengths connected to single-side end closure panels  26   b . Referring again to  FIG.  1   , the figure illustrates yet another arrangement of modular single-side linear units  28 , a single-side end cap  32 , and a single-side end closure panel  26   b . These assemblies are only a few examples of arrangements that can be created with the linear units  20 / 28 , the corner units  22 / 30 , and end caps  24 / 32  of the system  12  in accordance with the present disclosure. 
     The plurality of modular units of the linear fireplace system  12  are interchangeably interconnectable to allow a designer, architect, builder, etc., to create a beautiful linear fireplace in any one of an expansive variety of arrangements for a selected installation. In one embodiment, the modular units have one or more connector end portions with a common interface construction, such that the connector end portion of one module can be securely and fixedly attached to a connector end portion of any other module of the assembly. Such a construction allows for very flexible interchangeability of modules to create many different linear fireplace assembly configurations. The modular units are also configured so they can be easily and quickly assembled on site at the installation location while avoiding the problems experienced in the prior art with transporting and installing pre-built custom fireplaces in remote installations. As a result, the system  12  can be significantly easier and less expensive to incorporate into an installation, either in new construction or in connection with a remodel of an existing structure. 
     In the illustrated embodiments, the system  12  has a plurality of linear fireplace units  20  of selected lengths. For example, the system  12  includes the see-through linear fireplace units  20  and single-side linear fireplace units  28  in 5-foot, 4-foot, and 3-foot lengths. In another embodiments, the system  12  can include the linear fireplace units  20 / 28  in other lengths, including but not limited to 7-foot, 5-foot, 3-foot, and/or 1-foot lengths. In addition, the see-through and single-side corner units  22  and  30  of the illustrated embodiment are arranged in a 90-degree corner configuration. Other embodiments can include see-through and/or single-side corner units arranged with different angular orientations, including but not limited to 30-degree, 45-degree, and/or a 60-degree corner arrangements. In yet other embodiments, the system  12  can include arcuate corner units (see-through or single-side) attachable to the linear units, the end cap units, or even to other corner units. The corner units  22  and  30  can also be provided in different lengths. 
     The system  12  of the illustrated embodiment also includes linear units  20 / 28 , corner units  22 / 30 , end caps  24 / 32 , and closure panels  26   a/b  of different heights to provide taller or shorter viewing areas  34  into the firebox  18  in which the fire is contained. For example, the linear units  20 / 28 , corner units  22 / 30 , end caps  24 / 32 , and closure panels  26   a/b  of the illustrated embodiment are provided with support frames and glass panels, discussed in greater detail below, configure to provide for 12-inch and 20-inch high viewing areas  34  into the fireboxes  18 . In other embodiments, the system can provide modular units with viewing areas  34  of different heights. 
     As indicated above, the system  12  includes multiple linear fireplace units  20 / 28 , corner units  22 / 30 , and end caps  24 / 32 . Each of these modular units includes a base portion  40  and a top portion  42  separated by support frames  44  and a plurality of glass panels  46  that act to define the height of the firebox  18  and associated viewing area.  FIG.  6    is an isometric view of the modular, see-through linear fireplace unit  20  of at least one embodiment. The illustrated linear unit  20  has a construction for use in an installation where people can see into the firebox  18  from the front and rear sides of the assembly  10 . The see-through linear unit  20  has a base portion  40   a  spaced apart from a top portion  42   a  by support frames  44   a , and a plurality of interior glass panels  46  and exterior glass panels  48 . The firebox  18  is formed between the base portion  40   a  and the top portion  42   a  and between a pair of the spaced apart interior glass panels  46   a . The exterior glass panels  48   a  are spaced outwardly apart from the interior glass panels  46   a  to define an air gap  50  or passageway to further isolate the firebox  18  from the exterior glass panels  48   a.    
     As discussed in greater detail below, the base portion  40  of the modular units contains gas lines  52  and fireplace control units  54  that are operatively connected to an elongated burner assembly  56  positioned at the bottom of the firebox  18 . The gas lines  52  are coupleable to a fuel gas source, and the gas lines carry the fuel gas to multiple segments of the burner assembly  56 . The fuel gas is ignited and burned in the firebox  18  above the burner assembly  56  and between the interior glass panels  46   a.    
     This arrangement of interior and exterior glass panels  46   a  and  48   a  between the base and top portions  40   a  and  42   a  allows a substantially unobstructed view into the firebox  18  from either side of the linear unit  20 . Accordingly, a viewer can see fully through the linear unit  20  and can see the flames in the firebox  18  from the front and rear sides of the see-through linear unit. The air gap  50  between the interior and exterior glass panels  46   a  and  48   a  provides an insulating space so the exterior glass panels  48   a  are not directly exposed to the flames in the firebox  18  and its associated heat. 
     The top portion  42   a  of the see-through linear unit  20  has an interior exhaust chamber  58  directly above and in direct communication with the firebox  18 . The exhaust chamber  58  is connected to an exhaust flue  60  that connects to a contained chimney or other exhaust duct  62  (shown in phantom lines) to carry the combustion exhaust away from the firebox  18  without entering the room in which the fireplace assembly  10  is installed. In at least one embodiment, the exhaust chamber  58  and/or the exhaust duct  62  can include a powered fan  63  (shown schematically in phantom lines) configured to facilitate the exhaust flow away from the firebox  18  and the exhaust chamber  58 . This powered exhaust configuration can include one or more fans with selected air flow capacities depending upon the size and configuration of the assembly and the amount of exhaust generated during operation. 
     The top portion  42   a  also has a combustion air intake flue  64  that connects to an exterior combustion air duct  65  or other fresh air source. As discussed in greater detail below, the combustion air intake flue  64  is connected to a combustion air chamber  66  in the top portion  42   a  that provides the fresh combustion air to a combustion air passage  68  in communication with the firebox  18  adjacent to the burner assembly  56 , thereby providing a flow of fresh combustion air that will facilitate the burning of the fuel gas in the firebox  18  with the fuel gas. 
     From the perspective of viewing the see-through linear unit  20  as shown in  FIG.  6 A , the see-through linear unit  20  has left and right connector end portions  70  and  72 , respectively, having commonly arranged structure (e.g., flat connection flanges, tabs, brace plates, and/or associated fasteners) that mates with and can be fastened to similarly configured mating structure (e.g., flanges, tabs, brace plates, and/or associated fasteners) of another see-through linear unit  20 , and/or a see-through end cap  24 , and/or a see-through corner unit  22 , and/or an end closure panel  26   a . In the illustrated embodiment, the left end portion  70  is shown connected to an end closure panel  26   a  that fully closes the left end of the see-through unit  20 , and the right end portion  72  is arranged to be securely connected with another selected mating module of the system  12  for a see-through linear fireplace assembly. The configuration of the connector end portions provides a butt joint between the modules, wherein the modules are fastened to each other at the base and/or top portions  40   a  and  42   a . Accordingly, the glass panels of adjacent modules are securely retained in a tight butt joint with no joining structure needed in the firebox for the adjacent abutted glass panels. 
       FIG.  6 B  is a partially cutaway and partially exploded isometric view of two linear units  20 / 28  of an embodiment interconnected in a straight line configuration, and a torsion bar assembly  71  spans between the two units. In some embodiments, two or more linear units  20 / 28  may be so long that additional support is needed to protect against the units&#39; top portions  42  from sagging or drooping across the span, which could cause misalignment between adjacent units. The torsion bar assembly  71  is configured to span across two or more adjacent linear units  20 - 28  and to provide such support to maintain alignment and prevent unwanted sagging or drooping. In the illustrated embodiment, the torsion bar assembly  71  includes one or more torsion rods  73  positioned in aligned elongated channels  75  extending through the top portions  42 , such that the one or more torsion rods  73  span substantially across the length of the adjacent linear units  20 / 28 . The one or more torsion rods  73  are connected to one or more adjustment members  75  configured to tightened and pull on the torsion rod(s)  73  to put the rod(s) in tension. Alternatively the adjustment members  75  may be loosened to reduce the tension in the torsion rod(s)  73 . 
     In the embodiment illustrated in  FIG.  6 B , the torsion rod assembly  71  includes a pair of interconnected torsion rods  73  spanning through and between two adjacent linear units  20 / 28 . At least the ends  79  of each torsion rod  73  are threaded, and each threaded end  79  screws into a threaded aperture of an adjustment devices  75 , such as an elongated hex-nut or the like. In the illustrated embodiment, adjacent torsion rods  73  are interconnected by a central hex-nut or other adjustment device  75  that has two opposing threaded apertures. The adjustment devices  75  connected to the left and/or right ends of the torsion rods  73  can be rotatably anchored to the top portion  42  by threaded anchors  81 . The top portion  42  of each of the linear unit  20 / 28  has apertures that provide access to the end and/or middle adjustment devices  75  that allows a person to engage and rotate the adjustment devices to tighten or loosen the torsion rods  73 , such as during the installation procedure. Accordingly, the torsion bar assembly  71  allows for the use of longer linear units  20 / 28  while avoiding difficulties with misalignment, sag, and/or droop. 
       FIG.  7    is an isometric view of a single-side linear fireplace unit  28  of an embodiment of the system  12 . The single-side linear unit  28  has a configuration for use in an installation wherein people will only be viewing the unit from one longitudinal side of the fireplace assembly (i.e., from the front side). The single-side linear unit  28  has a construction very similar to the see-through linear unit  20  discussed above regarding  FIG.  6    (so it need not be repeated), except along the rear side of the unit. The single-side linear unit  28  has the firebox  18  defined by interior front glass panels  46  spaced apart from an interior rear panel  46   d . The interior rear panel  46   d  can be a transparent, translucent, or opaque panel. In one embodiment, the interior rear panel  46   d  is a glass panel similar to the interior front panel  46   b . The rear side of the unit  28  includes a substantially opaque or translucent rear closure panel  74  generally parallel to and spaced apart from the rear interior glass panel  46   d . The rear closure panel  74  is connected along its top and bottom edges to the units top portion  42   b  and the base portion  40   b , respectively, to retain the closure panel  74  apart from the rear interior glass panel  46   b  while still providing an air gap  50  or passageway therebetween. Accordingly, the single-side linear unit  28  is configured so a viewer can see into the firebox  18  and see the flames therein during operation of the unit, but at least the rear closure panel  74  blocks the viewer from seeing fully through the unit past the unit&#39;s rear side. 
     In at least one embodiment, the interior rear panel  46   d  can be a single panel or a plurality of aligned modular panel sections  46   d ′. In another embodiment, the closure panel  74  can be formed by a plurality of panel sections. The panel sections can be decorative panel sections made of one or more selected suitable materials, such as metal, opaque glass, or the like, with a selected color, texture, image, or decorative pattern. The panel sections can be provided with a uniform construction so as to be interchangeable. Accordingly, a user or manufacturer can provide assemblies  10  with the firebox areas having different aesthetic appearances by using different panel segment that can be easily and quickly installed during the original installation or during a retrofit for maintenance procedure. 
     In the illustrated embodiment of the single-side linear unit  28 , the rear sides of the base and top portions  40   b  and  42   b  are configured to connect to the rear closure panel  74  so the lateral distance between the closure panel  74  and the rear interior glass panel  46  can be less than the distance between the rear interior and exterior glass panels  48  and  48  of the see-through linear unit  20  discussed above, while still maintaining substantially the same performance and visual presentation of the flames in the firebox  18 . 
     The system  12  includes modular corner units configured to connect to the linear fireplace units, including the see-through linear units  20  and single-side linear units  28 . The modular corner units are also configured to connect to the modular end caps, including the see-through end cap  24  and single-side end cap  26 .  FIGS.  8 A and  8 B  are isometric views of a see-through corner unit  22  of an embodiment of the system  12 . The corner unit  22  is a 90-degree corner unit having L-shaped base and top portions  40   c  and  42   c  spaced apart from each other by a support frame  44   c  and interior and exterior glass panels  46  and  48 , respectively, to define the firebox  18  therebetween. The corner base portion  40   c  and the corner top portion  42   c  have structural configurations substantially similar to the base portion  40   a  and top portion  42   a  discussed above, except for the L-shape of the unit. The corner unit  22  has orthogonally oriented end portions  76  and  78  configured to mate with the respective left or right end portion  70  or  72  of the see-through linear unit  20  ( FIG.  6   ) in a modular manner. The corner unit&#39;s end portions  76  and  78  are also configured to mate with a see-through end cap  24  and an end closure panel  26   a  in a modular manner. 
     As seen in  FIGS.  8 A and  8 B , the base and top portions  40   c  and  42   c  of the see-through corner portion  22  have a plurality of flanges  80   a  and/or tabs  82   a  positioned to align with and be fastened to similar flanges  80   b  and/or tabs  82   b  on the end portions  70  and  72  of the see-through linear unit  20  ( FIG.  6   ). The end caps  24  have similar arrangements of flanges and tabs that connect with the flanges  80   a/b  and tabs  82   a/b  of the corner and linear units  22  and  20 , respectively, when joined together in a selected assembly. Accordingly, when the see-through corner unit  22  is attached to the see-through linear unit  20 , the base portions  40   a / 40   c , glass panels  46 / 48 , and top portions  42   a / 42   c  are axially aligned and cleanly abut to provide an elongated, modular, substantially continuous burner assembly  56 , firebox  18 , exhaust chamber  58 , combustion air chamber  66 , and the air gaps  50  between the glass panels  46 / 48 . 
       FIG.  9    is an isometric view of the single-side corner unit  30  of an embodiment of the system  12 . The single-side corner unit  30  is a 90-degree corner unit that has a construction similar to the see-through corner unit  22  described above, except along the rear side of the unit. Similar to the single-side linear unit  28 , the rear side of the corner unit  30  includes an opaque or translucent rear closure panel  88  generally parallel to and spaced apart from the rear interior glass panels  46   c . The single-side corner unit  30  has base and top portions  40   d  and  42   d , respectively, having structural configurations substantially similar to the base and top portions  40   b  and  42   b  of the single-side linear unit  28  discussed above except for the L-shape of the unit. The corner unit&#39;s orthogonally oriented end portions  90  and  92  are configured to mate with the respective left or right end portions  70   b  and  72   b , respectively, of the single-side linear unit  28  ( FIG.  7   ) in a modular manner. The single-side corner unit&#39;s end portions  90  and  92  are also configured to mate with the single-side end cap  24  and the end closure panel  26   b  in a modular manner. The end portions  90  and  92  of the single-side corner unit  28  each have a plurality of flanges  80   c  and tabs  82   c  positioned to fasten to similar flanges  80   d  and tabs  82   d  on the end portions  70   b / 72   b  of the single-side linear unit  28  ( FIG.  7   ). The single-side end cap  32  and closure end panel  26   b  have similar mounting structures that connect with the flanges  80   c/d  and tabs  82   c/d  of the single-side linear and corner units  28 / 30  when joined together in a selected assembly. Accordingly, when the single-side corner unit  30  is modularly attached to the single-side linear unit  28 , the base portions  40   b/d , glass panels  46 / 48 , and top portions  42   b/d  are also axially aligned and cleanly abut to provide an elongated, modular, substantially continuous burner assembly  56 , firebox  18 , exhaust chamber  58 , combustion air chamber  66 , and the air gaps  50  between the glass panels  46 / 48 . 
       FIG.  10    is an isometric view of the see-through end cap  24  of the system  12 . The end cap  24  has a base portion  94   a , a top portion  96   a , and a support frame  98   a  extending therebetween. The base and top portions  94   a  and  96   a  are configured to attach to the ends of the base and top portions  40   a/c  and  42   a/c  of the see-through linear and corner units  20 / 22 , thereby providing closure structure for the units. The top portion  96   a  is also configured to provide closure structure to the exhaust chamber  58  and the combustion air chamber  66  ( FIG.  6   ) while keeping the chambers substantially isolated from each other to avoid mixing the outgoing exhaust and the incoming combustion air within the top portions of the units. 
     The support frame  98   a  of the illustrated embodiment has a pair of spaced apart vertical supports  100  positioned to be immediately adjacent to the ends of the interior glass panels  46  of the linear and corner units  20  and  22  ( FIGS.  6  and  8 B ), respectively discussed above. The end cap  24  also has an interior glass end panel  102  spanning between the vertical supports  100  of the support frame  98   a . The interior glass end panel  102  and vertical supports  100  provide a closure to the end of the firebox  18  of the linear unit  20  ( FIG.  6   ) or the corner unit  22  ( FIGS.  8 A / 8 B) to which the end cap  24  may be attached. The end cap  24  also includes an exterior end glass panel  104   a  spanning between exterior side glass panels  106   a  to define an air gap  108   a  around the end of the firebox  18  ( FIG.  6   ) of a selected assembly. The exterior side glass panels  106   a  are positioned to abut and align with the exterior glass panels  48  of the see-through linear units  20  ( FIG.  6   ) and/or the see-through corner unit  22  ( FIG.  8 B ) when the end cap  24  is attached to the mating modular components. In one embodiment, the exterior glass side panels  106   a  can be integral to the exterior glass panels of a mating linear or corner unit. Accordingly, a continuous space is provided around the firebox  18  of an assembly  10  between the interior and exterior glass panels  46 / 48 / 102 / 104 / 106  to isolate the firebox  18  from the outer surfaces of the fireplace assembly of a selected installation. 
       FIG.  11 A  is an isometric view of the single-side end cap  26  of the system  12 . The single side end cap  26  has a base portion  94   b , a top portion  96   b , and support frame  98   b  generally similar to the see-through end cap  24  discussed above. The single-side end cap  26  also has an interior glass end panel  102   b  spanning between the vertical supports  100   b  of the support frame  98   b  that provides a closure to the end of the firebox  18  of the single-side linear unit  28  ( FIG.  7   ) or the single-side corner unit  30  ( FIG.  9   ) to which the end cap  26  may be attached. The end cap  26  has an exterior glass end panel  104   b  and an exterior glass side panel  106   b  similar to the see-through end cap  24 , and the exterior rear wall is formed by an opaque or translucent rear closure panel  74   c  that abuts and aligns with the rear closure panel  74   a  or  74   b  of a single-side linear unit  28  ( FIG.  7   ) and/or corner unit  30  ( FIG.  9   ) when the units are interconnected. In one embodiment, the exterior glass side panel  106   b  can be integral to an exterior glass panel of a mating linear or corner unit. The single-side end cap  26  provides an end closure of the fireplace while allowing a person to see axially into the firebox  18  through the viewing space between the top and base portions  96   b  and  94   b.    
       FIG.  11 B  is an isometric view of the end closure panel  26   b  for a single-side assembly. The end closure panel  26   b  is an opaque or translucent panel having a shape that mates with the end portions of the single-side linear unit  28  ( FIG.  7   ) and/or the single-side corner unit  30  ( FIG.  9   ) so as to fully close and seal the end of the unit to which the panel is attached. The end closure panel  26   a  for the see-through assembly has a similar structure but is shaped to mate with the end portions of the see-through linear unit  28  ( FIG.  6   ) and/or the see-through corner unit  30  ( FIG.  8 B ) so as to fully close and seal the end of the unit to which the panel is attached. The end closure panels  26   a  and  26   b  of the illustrated embodiment can include a gas line fittings  110  that communicates with the gas lines  52  in the linear or corner units discussed above to provide the fuel gas to the modular fireplace assembly  10 . The end closure panels  26   a  and  26   b  can also include an electronic interface  112  that operably connects with the fireplace control units  54  of the selected linear and/or corner units  20 / 28  or  22 / 30 , respectively, of the resulting modular linear fireplace assembly  10 . Similar gas line fittings  110  and/or electronic interfaces  112  can be provided in the base portions  94   a/b  of the single-side end cap  26  or the see-through end cap  24  discussed above. 
     In the illustrated embodiment, at least the modular linear and corner units  20 ,  22 ,  28 ,  30  include an alignment track system  120  configured to allow for quick and easy axial alignment between adjacent interconnected modules during assembly of the units in a selected installation. This alignment track system  120  greatly increases the ease and accuracy of installing the modular units at the installation location during construction or a remodel, thereby decreasing the costs and labor intensity of installing the assembly  10  in a selected location.  FIG.  12    is a bottom isometric view of the modular linear fireplace assembly  10  of  FIG.  4    showing the alignment track system  120  on the bottom of the assembly. The alignment track system  120  includes an elongated track member  122  having a pair of parallel, spaced apart support tracks  124  interconnected by a planar mounting web  126 . The track member  122  can be a unitary member or can be made of a plurality of interconnected segments to define the track member with a selected length. The track member  122  can include one or more support inserts  128  positioned on the web  126  between the support tracks  124  to provide structural support for the modular units inserted into the track, as discussed in greater detail below. 
     As seen in  FIGS.  12 ,  14 , and  16   , the base portion  40  of each modular linear or corner unit includes a pair of parallel alignment rails  130  spaced apart and positioned to fit within the track member  122  supported atop the support tracks  124  ( FIG.  12   ). The alignment rails  130  are configured to properly position and coaxially align adjacent linear or corner modular units  20 ,  22 ,  28 ,  30  positioned in the track member  122 , such that the adjacent modular units  20 ,  22 ,  28 ,  30  will be in the exact position to be interconnected during an assembly process. The track member  122  and alignment rails  130  also allow a modular unit to be placed on the support tracks  124  and then slid axially along the support tracks  124  to a final selected position during an assembly procedure, thereby greatly increasing the ease of moving and positioning the modular units during assembly at the installation site. 
     When a selected modular linear fireplace assembly  10  is assembled and installed at a selected site, the elongated track member  122  is mounted and secured in place on the selected building support structure that will support the fireplace assembly. In the illustrated embodiment, the track member  122  can be mounted using a plurality of fasteners that extend through the web  126  and/or through portions of the support tracks  124  that will not engage or otherwise interfere with the alignment rails  130  on the modular units. The support inserts  128  ( FIG.  13   ) can be positioned on the track member  122  between the support tracks  124  in a location to help support or distribute the weight of the modular units of the linear fireplace assembly  10 . The track member  122  can be arranged in a straight line configuration, or an L-shaped configuration or other configuration to match the layout of the interconnected modules of the selected linear fireplace assembly  10 . 
     After the track member  122  is installed, a first modular fireplace unit  20 ,  22 ,  28 ,  30  can be positioned on the track member  122  with the alignment rails  130  in engagement with the support tracks  124 , as shown in  FIG.  15   . The installed modular unit can then be axially positioned along the track member  122  to a final or other desired location. Then a second modular unit  20 ,  22 ,  28 ,  30 , such as a linear or corner unit, can be positioned in the track member  122  with its alignment rails  130  engaging the support tracks  124 , and the second modular unit adjusted axially to abut the end portion of the first modular unit. Accordingly, the track member  122  spans across the abutting joint between the adjacent linear fireplace modules. The interface between the support tracks  124  and alignment rails  130  insures proper axial alignment of the abutting modular units. The additional modular units can be placed on the track member  122  and joined or otherwise secured to the other modular units in accordance with the arrangement of the selected assembly  10 . The end caps  24 ,  26  or end closure panels  26  can also be installed and fastened in place on their respective adjacent modular units to enclose the ends of the selected modular assembly  10 . 
       FIG.  17    is a cross-sectional isometric view showing a single-side linear unit  28  of an embodiment, and  FIG.  18    is a top isometric view of the base portion  40   a  of the see-through linear unit  20 . The base portions  40   a/b  of the see-through units and the single-side units have very similar constructions except for the interface with the rear closure panel  74  (for the single-side units) and the interface with the rear exterior glass panel  48  (for the see-through units). The base portions  40  of the corner units and the end caps also have similar constructions, such that the following description substantially applies to all of the base portions. 
     The base portions  40  have a generally U-shaped body  140  with a bottom panel  142  extending between front and rear side panels  144  and  146 . The alignment rails  130  of the alignment track system  120  are attached to the under surface of the bottom panel  142 . The base portion  40  also has a pair of parallel, spaced apart elongated front and rear interior support structures  148  and  150  generally parallel to the front and rear side panels  144  and  146 . The front and rear interior support structures  148  and  150  are configured to receive and support the burner assembly  56  that includes a plurality of aligned burner segments  152  extending axially along the length of the base portion  40 . Support screens  154  are positioned and supported along the front and rear sides of the burner segments  152 . The support screens  154  provide a perforated surface in the firebox  18  adjacent to the burner segments  152  that can support noncombustible decorative materials, such as stones, simulated coal embers, clear or colored glass pieces, etc., adjacent to or over the burner segments  152 . Accordingly, the fuel gas from the burner segments  152  can filter through the decorative material and burn in the firebox  18  above the burner segments  152 , the support screens  154 , and any decorative material thereon. 
     The interior support structures  148  and  150  also help support the gas lines  52  operably connected to the burner segments  152  in a conventional manner. The ends of the gas lines  52  adjacent to the end portions of the modular units with conventional fittings that allow the gas lines  52  of adjacent modular units to be interconnected. The front interior support structure  148  and the front side panel  144  are configured to help support and contain the electronic fireplace controls  54 , including the burner controls that control the flow of gas from the gas lines  52  to the burner segments  152  during operation of the fireplace assembly  10 . 
     As seen in  FIG.  18   , the front side panel  144  can include one or more access panels  156  that provide access to the burner segments  152 , the fireplace controls  54 , and the gas lines  52 . These access panels  156  provide open and easy access to the module&#39;s internal components during assembly and or during adjustment of the assembly after installation. The burner segments  152  of the illustrated embodiment can include a single segment that extends the full-length of the base portion  40 . Alternatively, the burner segments  152  can include a plurality of segments within a single module, and each segment is configured to connect to the gas lines  52  to receive the flow of fuel gas therein during operation of the assembly. In one embodiment, the burner segments  152  are one-foot segments each with a uniform or common constructions, such that the segments are all interchangeable and can be installed in the base portion to form a substantially continuous linear burner assembly  56  under the support screens  154  for uniform distribution of the combustion gas into the firebox during operation. Each base portion  40  can include one or more electronic fireplace control units  54 , and the fireplace controls  54  of adjacent modules can be operatively coupled together and connected to a master controller of the modular linear fireplace assembly  10 . 
     The control units  54  and/or the master controller can include on-board manipulatable, switches, or controls manipulatable by a user during operation of the assembly  10  to control aspects of the assembly. The control unit  54  and/or the master controller can be coupled to a wireless remote control unit that allows a user to control the assembly remotely. In one embodiment, the control unit  54  and/or the master controller can be configured with a conventional “Wi-Fi” control protocol coupled to a control application that can be downloaded onto a smartphone, tablet, laptop, computer, or another personal electronic device (PED). Accordingly, as an example, a user can launch the application on his or her smartphone and remotely control operation of the fireplace assembly  10  via the phone and the associated application. 
     The base portion  40  can also include a plurality of lights, such as LED lights  158  on a light strip connected to, as an example, the front side panel  144  adjacent to the bottom of the front exterior glass panel  48   a . The lights  158  are also coupled to the fireplace controls  54  and configured to illuminate the interior of the modular units. The lights  158  can be configured to provide a variety of colors, patterns, and/or sequences by selectively illuminating the lights  158  during use of the modular, linear fireplace assembly  10 . In the illustrated embodiment, the LED lights are attached to the body&#39;s front and/or rear side panels  144 / 146  below its top edge and facing upwardly, so the light projects up into the firebox. In one embodiment, the lights  158  can be controlled remotely by a user via the remote control device and/or the application on the user&#39;s smartphone, tablet, computer, laptop, or other PED. 
     As seen in  FIGS.  17  and  18   , the base portion  40  has a plurality of glass support rails  160  that receive and support the interior and exterior glass panels  46  and  48  ( FIG.  7   ). The top edge portion of the body&#39;s front side panel  144  has a front exterior glass support rail  160   a  that securely engages and supports the unit&#39;s front exterior glass panel  48   a . The front and rear interior support structures  148  and  150  also include interior glass support rails  160   b  and  160   c , respectively, that securely engage and support the unit&#39;s interior glass panels  46   a/b  with the burner segments  152  and the firebox  18  therebetween. The base portion  40  of each see-through unit  20  ( FIG.  18   ),  22  ( FIG.  8 B ),  24  ( FIG.  10   ) has a rear exterior glass support rail  160   d  that securely engages and supports the unit&#39;s rear exterior glass panel  48   b . In the single-side units  28  ( FIG.  7   ),  30  ( FIG.  9   ),  32  ( FIG.  11 A ), the rear side panel  146  of the base portion&#39;s body  140  does not have a glass panel rail. The top edge portion of the rear side panel  146  is connected to the bottom edge of the rear closure panel  74 . This configuration with the glass support rails  160  allows glass panels to be easily installed, removed, and/or replaced. 
     The glass panels  46 / 48  of the assemblies are also secured to the top portions  42  of the modular units via similar glass support rails  162 .  FIG.  19 A  is a bottom isometric view of the top portion  42   a  of the see-through linear unit  20  ( FIG.  6   ), and  FIG.  19 B  is a cross-sectional view taken substantially along lines  19 B- 19 B of  FIG.  19 A .  FIG.  17    shows the top portion  42   b  of the single-side linear unit  28 . The top portions  42  of the see-through units and the single side units are substantially similar, with the exception of the interface between the rear closure panel  74  or the rear exterior glass panel  48   b . Accordingly, the following discussion applies to all of the top portions  42 . Each top portion  42  has a body portion  166  with an inverted, generally U-shaped cross sectional shape. The body portion  166  has a front side portion  168  spaced apart from a rear side portion  170 , and each of the front and rear side portions have outwardly flared lower portions  172 . Each of the outwardly flared lowered portions  172  of the see-through units have upper exterior glass support rails  162   a  and  162   d  positioned vertically above the exterior glass support rails  160   a  and  160   d , respectively, of the corresponding base portion  40  ( FIG.  18   ) discussed above. The upper exterior glass support rails  162   a/d  securely engage and support the exterior glass panels  48 . As seen in  FIG.  17   , the top portions&#39; rear side portion  170  of the single-side units are fastened or otherwise securely connected to the top edge of the rear closure panel  74 . 
     The body  166  of each top portion  42  has an interior frame structure  174  attached to the front and rear side portions  168  and  170 . The frame structure  174  is attached to and carries a divider channel  176  that has an inverted, generally U-shaped cross-sectional. The divider channel  176  is supported interior of and spaced apart from the front and rear side portions  168  and  170  so as to define an upper portion  178  of the combustion air passageway  68  around the outside of the divider channel  176  and adjacent to the body&#39;s front and rear side portions  168  and  170 . The U-shaped divider channel  176  is positioned above the firebox  18  between the interior glass panels  48  so as to define an exhaust passageway  180  inside of the divider channel  176 . The bottom edges of the divider channel  176  are connected to spaced-apart seal clips  182  also attached to the frame structure  174 . These seal clips  182  also carry the upper interior glass support rails  162   b  and  162   c  that securely receive the top edges of the interior glass panels  46   a  and  46   b , respectively. Accordingly, the interior glass panels  46 , the seal clips  182 , and the divider channel  176  fully separate and isolate the firebox  18  and the associated exhaust passageway  180  from the combustion air passageway  68 , which extends around the divider channel  176  and between the interior and exterior glass panels  46  and  48  (or the rear interior glass panel  46   b  and the rear closure panel  74  of the single-side units). 
     As seen in  FIGS.  17  and  19 B , each the top portion  42  includes an elongated, tented baffle  184  supported atop the seal clips  182 . The tented baffle  184  includes a plurality of slots  186  formed along the length of the baffle above the firebox  18 . The tented shape of the baffle  184  and the number and positioning of the slots  186  help control and distribute the combustion exhaust from the firebox  18  into the exhaust passageway  180  within the divider channel  176 . As discussed above, the exhaust flue  60  is attached to the top of the body portion  166  above the firebox  18 . The exhaust flue  60  extends partially into the body portion  166  and sealably connects to the top of the divider channel  176  so combustion exhaust from the firebox can flow through the exhaust passageway  180  and into the exhaust flue  60  and the associated exhaust duct  62 . 
     Each top portion  42  of at least the modular linear and corner units is configured to include an exhaust flue. A multi-module assembly  10 , such as the assembly shown in  FIGS.  1 ,  3  and  4   , may only need one exhaust flue  60  and exhaust duct  62  to handle the combustion exhaust. In this configuration, other exhaust flues can be removed and the associate opening in the top of the body portion  42  is sealed with a closure panel  188 , as shown in  FIGS.  3  and  4   . In other embodiments having larger or longer assemblies, such as shown in  FIG.  2   , can include more than one modular top portions having an integrated exhaust flue and exhaust duct configuration. 
     Each modular linear units  20 ,  28  is also configured to have the air intake flue  64  connected to the top of the body portion  166  and in communication with the combustion air passage  68  above and around the outside of the divider channel  176 . In some embodiments, a modular corner unit  22 ,  30  can also have a combustion air intake flue. In other embodiments, multiple combustion air intake flues may not be needed, such that an air intake flue and its associated aperture in the body portion  166  can be sealed with a closure panel. 
       FIG.  20 A  is the cross-sectional isometric view of  FIG.  17    illustrating the combustion air flow path  190  through the modular fireplace unit to the combustion chamber in the firebox  18 . Fresh combustion air from the air intake duct  65  (shown in broken lines) enters the assembly  10  through the combustion air intake flue  64  and flows into the combustion air chamber  66  in the top portion  42 . The combustion air flows through the combustion air chamber  66 , around the exterior of the divider channel  176 , and flows downwardly through the forward portion  192  of the combustion air passage  68  between the forward interior and exterior glass panels  46   a  and  48   a , and through the rear portion  194  of the combustion air passage  68  between the rear interior and exterior glass panel  46   b  and the rear closure panel  74 . In the see-through units, the rear portion  194  of the combustion air passage  68  flows between the rear interior and exterior glass panels  46   b  and  48   b . The combustion air continues to flow into and through the base portion  40  and upwardly into the firebox  18  through the support screens  154  adjacent to the burner segments  152 . The combustion air facilitates combustion of the fuel gas in the firebox  18  and generation of the aesthetically pleasing flame in the firebox  18 . Although the embodiment illustrated in  FIG.  20 A  is a single-side linear unit for purposes of illustration, a substantially similar combustion air flow path is provided through the see-through and single-side corner units. A similar combustion air flow path can also be provided in the end units. 
     When the fuel gas and combustion air burn in the firebox  18 , the resulting combustion results in exhaust that flows upwardly in the firebox  18  away from the burner assembly  56  along an exhaust path  196  into the exhaust passageway  180  in the top portion&#39;s divider channel  176 , which is isolated from the upper portion  178  of the combustion air passage  68 . The flow of exhaust exits the divider channel  176  through the exhaust flue  60  and flows into the exhaust duct  62  away from the assembly  10 . 
     The configuration of the modular linear units with the air gap and the flow of combustion air exterior of the firebox  18  between the interior and exterior glass panels  46  and  48 , respectively, (or between the rear interior glass panel and the rear closure panel  74 ) keeps the exterior surface of the units relatively cool. As the fresh combustion air flows through the combustion air passage  68  over the interior glass panels  46   a/b  and around the firebox  18 , the air flow carries heat away from the exterior glass panels  48   a/b  and/or the rear closure panel  74 , and the partially heated combustion air flows into the firebox  18  past the burner assemblies  56 . The fresh combustion air also flows through the base portions  40  so as to keep the lights  158  and the electronic controls  54  cooled during operation of the fireplace assembly  10 . Further, the configuration of the modular units, and the flow of fresh combustion air help maintain the exterior of the units at relatively low temperatures during operation and burning of the fuel gas in the firebox  18 . As an example, the exterior temperatures of the units remain well below 170° F., and typically are only up to approximately 130° F. 
     As discussed above, the modular units, such as the linear units  20 , of the fireplace assembly  10  have the connector ends with the common construction that allows interconnection of selected modules without having any visible interconnecting structure in the firebox except for the abutting glass panels. Once the linear units  20  are interconnected with the other modules in a fully installed assembly  10 , the adjacent base and top portions  40  and  42  are securely fixed in place relative to each other so that excessive vertical loads are not carried by or applied to the glass panels. Before the modular units are installed, such as during shipping or storage, the system of at least one embodiment includes supportive shipping brackets  250  that help support the base and top portions  40  and  42  of the units.  FIG.  21    is an isometric view of a modular, see-through linear unit  20  in a shipping configuration without the glass panels installed and with the shipping brackets  250  securely connected to the base and top portions via the glass support rails  160 / 162 , such as the exterior glass support rails  160   a/d  and  162   a/d.    
     The shipping brackets  250  each have adjustably interconnected bottom and top members  252  and  254 . The bottom member  252  has a linear bottom edge  256  that fits into the bottom exterior glass support rail  162   a/d , and the top member  254  has a linear top edge  258  that fits into the top exterior glass support rail  160   a/d . The top and bottom members  254  and  252  are interconnected by one or more axially adjustable connectors  260 , such as threaded shafts that can be rotated or otherwise adjusted to increase or decrease the distance between the top and bottom members  254  and  252 . Accordingly, the connectors  260  can be adjusted to secure or release the shipping brackets  250  from the respective base and top portions of the modular unit. 
     In one embodiment, two shipping brackets  250  are used on each end of the see-through linear units  20 . Only one shipping bracket is needed for each end of the single-sided linear unit because the back closure panel  74  helps support the base and top portions  40  and  42  during shipping and/or storage. When more than one shipping bracket is used on an end of a unit, the shipping brackets can be braced together with a connector  262  to provide additional structural support and security for the modular unit during shipping and/or storage. In addition, the shipping brackets  250  can be constructed such that portions of the shipping brackets  250  can be used as hardware to securely fasten the ends of the linear units  20 / 28  to the ends of abutting modules during installation. 
     The modular units&#39; construction and resulting low exterior temperature during operation of the assemblies also allows the assemblies to be built into installations that have combustible building products immediately adjacent to the assembly. As an example, the top portion  42  of the unit illustrated in  FIG.  19 B  has upper finishing rails  198  and adjacent to the exterior glass support rails  162   a/d . Similarly, the base portion  40  of the modular unit illustrated in  FIG.  18    has lower finishing rails  200  adjacent to the exterior glass support rails  162   a/d . When the modular linear fireplace assembly  10  is assembled and installed at an installation, combustible or noncombustible finish building materials, such as wall covering material or the like, can extend all the way to the finishing rails  198  and  200 , so as to hide the base and top portions  40  and  42  of the assembly. This ability to use combustible building products up to the finishing rails  198  and  200  provides builders and designers significantly more flexibility for aesthetically pleasing installations. 
     From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the invention. Additionally, aspects of the invention described in the context of particular embodiments or examples may be combined or eliminated in other embodiments. Although advantages associated with certain embodiments of the invention have been described in the context of those embodiments, other embodiments may also exhibit such advantages. Additionally, not all embodiments need necessarily exhibit such advantages to fall within the scope of the invention. Accordingly, the invention is not limited except as by the appended claims.