Condensing boiler and water heater

Abstract

A boiler and method of operating a boiler are disclosed. The boiler generally includes a housing defining an enclosed region and a plurality of heat exchange conduits at least partially positioned within the enclosed region of the housing and arranged into an interior column and an exterior column. A baffle is at least partially positioned within the enclosed region of the housing and positioned between the interior column and the exterior column of heat exchange conduits. The baffle and the housing together define a constricted region. The heat exchange conduits of the exterior column are positioned within the constricted region. The constricted region defines a path for directing the flow of products of combustion adjacent the heat exchange conduits of the exterior column thereby facilitating the exchange of heat between the products of combustion and water within the heat exchange conduit of the exterior column.

1 . A boiler comprising:
 a housing defining an enclosed region;   a plurality of heat exchange conduits at least partially positioned within the enclosed region of the housing, each heat exchange conduit having a first end spaced apart from a second end thereof and a water passageway defined between said first end and said second end, said plurality of heat exchange conduits being arranged into an interior column and an exterior column, each column including at least one heat exchange conduit;   a burner positioned to deliver products of combustion into the enclosed region of the housing for heat exchange with water contained within said plurality of heat exchange conduits; and   a baffle at least partially positioned within said enclosed region of said housing and positioned between the interior column and the exterior column of said heat exchange conduits, said baffle and said housing together defining a constricted region and said at least one heat exchange conduit of said exterior column being positioned within said constricted region;   said constricted region being configured to direct the flow of products of combustion adjacent said at least one heat exchange conduit of said exterior column thereby facilitating an exchange of heat between the products of combustion and water within said at least one heat exchange conduit of said exterior column.   
   
   
       2 . The boiler of  claim 1 , wherein a cross-sectional area of said constricted region is sized to increase the velocity of the products of combustion flowing therethrough. 
   
   
       3 . The boiler of  claim 1 , wherein each heat exchange conduit is substantially “U” shaped, and said first end and said second end of each heat exchange conduit are positioned to face in substantially the same direction. 
   
   
       4 . The boiler of  claim 3 , said first ends and said second ends of said plurality of heat exchange conduits being arranged on a common plane. 
   
   
       5 . The boiler of  claim 1 , wherein said at least one heat exchange conduit of said exterior column is positioned outwardly from said at least one heat exchange conduit of said interior column. 
   
   
       6 . The boiler of  claim 1 , said burner being positioned to deliver the products of combustion into a region circumscribed by the at least one heat exchange conduit of said interior column. 
   
   
       7 . The boiler of  claim 1  further comprising an inlet conduit coupled to introduce water into said first end of said at least one heat exchange conduit of said exterior column. 
   
   
       8 . The boiler of  claim 7  further comprising a bypass conduit coupled to direct at least a portion of water within said inlet conduit into said second end of said at least one heat exchange conduit of said interior column or the first end or the second end of said at least one heat exchange conduit of said exterior column. 
   
   
       9 . The boiler of  claim 8 , wherein said bypass conduit and said inlet conduit are positioned at least partially outside of said enclosed region of said housing. 
   
   
       10 . The boiler of  claim 1  further comprising an outlet conduit being positioned to receive water from either the first end or the second end of said at least one heat exchange conduit of said interior column. 
   
   
       11 . The boiler of  claim 1  further comprising an exhaust outlet positioned in flow communication with said constricted region for exhausting said products of combustion from said enclosed region of said housing. 
   
   
       12 . A boiler comprising:
 a housing defining an enclosed region;   a plurality of heat exchange conduits at least partially positioned within said enclosed region, each heat exchange conduit having a first end spaced apart from a second end thereof and a water passageway defined between said first end and said second end, said plurality of heat exchange conduits being arranged into an interior column and an exterior column, each column including at least one heat exchange conduit;   an inlet conduit coupled to introduce water into said first end of said at least one heat exchange conduit of said exterior column;   an outlet conduit positioned to deliver water from either said first end or said second end of said at least one heat exchange conduit of said interior column; and   a bypass conduit coupled to direct at least a portion of the water from said inlet conduit into either said first end or said second end of said at least one heat exchange conduit of said interior column or said exterior column, wherein said inlet conduit, said outlet conduit and said bypass conduit are positioned at least partially outside of said enclosed region of said housing.   
   
   
       13 . The boiler of  claim 12  further comprising an adjustable restriction positioned on the bypass conduit for selectively directing at least a portion of the water from said inlet conduit into either said first end or said second end of said at least one heat exchange conduit of said interior column or said exterior column. 
   
   
       14 . The boiler of  claim 12 , wherein said interior column includes a plurality of heat exchange conduits and the exterior column includes a plurality of heat exchange conduits. 
   
   
       15 . The boiler of  claim 14  further comprising a header communicating with said first ends of said interior column of heat exchange conduits and said first ends of said exterior column of said heat exchange conduits, wherein said inlet conduit is positioned to deliver water into said first header. 
   
   
       16 . The boiler of  claim 15  further comprising a partition within said header positioned to isolate one or more of said first ends of said interior column of said heat exchange conduits from one or more of said first ends of said exterior column of said heat exchange conduits. 
   
   
       17 . The boiler of  claim 15  wherein the header is configured to direct water from said first end of at least one heat exchange conduit of said interior column to the first end of at least one adjacent heat exchange conduit of said interior column. 
   
   
       18 . The boiler of  claim 15  wherein the header is configured to direct water from the first end of at least one heat exchange conduit of said exterior column to the first end of at least one adjacent heat exchange conduit of said exterior column. 
   
   
       19 . The boiler of  claim 14  further comprising a header communicating with said second ends of said interior column of said heat exchange conduits and said second ends of said exterior column of said heat exchange conduits,
 wherein said outlet conduit is positioned to receive water from said header, and   wherein said bypass conduit is coupled to deliver water into said header.   
   
   
       20 . The boiler of  claim 19  further comprising a partition within said header positioned to direct water from said second end of at least one heat exchange conduit of said exterior column into said second end of at least one heat exchange conduit of said interior column. 
   
   
       21 . The boiler of  claim 19  wherein the header is configured to direct water from the second end of at least one heat exchange conduit of said interior column to the second end of at least one adjacent heat exchange conduit of said interior column. 
   
   
       22 . The boiler of  claim 19  wherein the header is configured to direct water from the second end of at least one heat exchange conduit of said exterior column to the second end of at least one adjacent heat exchange conduit of said exterior column. 
   
   
       23 . The boiler of  claim 13 , said adjustable restriction comprising a valve. 
   
   
       24 . A method of operating a boiler including a heat exchanger positioned at least partially within an enclosed region of a boiler housing, said method comprising the steps of:
 introducing water into a first conduit of the heat exchanger;   transferring water from the first conduit to a second conduit of the heat exchanger, wherein exterior surfaces of the first conduit and the second conduit are physically separated by a baffle;   delivering products of combustion into the enclosed region of the boiler housing for heat exchange with water contained within the second conduit; and   directing the products of combustion into a constricted region of the boiler housing defined between the baffle and the boiler housing for heat exchange with water contained within the first conduit.   
   
   
       25 . The method of  claim 24 , wherein the introducing step comprises introducing water into the first conduit through an inlet conduit at least partially positioned outside of the boiler housing. 
   
   
       26 . The method of  claim 25 , wherein the introducing step further comprises directing at least a portion of the water from the inlet conduit into the second conduit. 
   
   
       27 . The method of  claim 24  further comprising the step of exhausting the products of combustion through an exhaust outlet positioned in flow communication with the constricted region. 
   
   
       28 . A method of operating a boiler including a heat exchanger positioned at least partially within an enclosed region of a boiler housing, said method comprising the steps of:
 introducing water through an inlet conduit into an end of at least one heat exchange conduit in an exterior column of heat exchange conduits;   delivering water through an outlet conduit from an end of at least one heat exchange conduit in an interior column of heat exchange conduits; and   directing at least a portion of the water through a bypass conduit from the inlet conduit into an end of at least one heat exchange conduit in the interior or exterior column of heat exchange conduits.   
   
   
       29 . The method of  claim 28  wherein the directing step comprises adjusting an adjustable restriction positioned on the bypass conduit to selectively direct at least a portion of the water through the bypass conduit. 
   
   
       30 . The method of  claim 28  wherein the directing step comprises directing at least a portion of the water into a header that is positioned in fluid communication with the end of the at least one heat exchange conduit in the interior or exterior column of heat exchange conduits. 
   
   
       31 . The method of  claim 30  wherein the directing step further comprises delivering the portion of water from the header into the end of the at least one heat exchange conduit in the interior or exterior column of heat exchange conduits.