Combustion system

Abstract

A combustion system includes: a furnace housing defining a combustion chamber therein and having a gas outlet in fluid communication with the combustion chamber; a plenum housing surrounding and cooperating with the furnace housing to define a plenum chamber therebetween, and having an air inlet and an air outlet which are in fluid communication with the plenum chamber; and a heat exchanger housing disposed outwardly of the plenum housing and having an air inlet in fluid communication with the air outlet of the plenum housing, an air outlet, a gas inlet in fluid communication with the gas outlet of the furnace housing, and a gas outlet.

1 - 3 . (canceled) 
   
   
       4 . A combustion system comprising:
 a furnace defining a combustion chamber that has a gas outlet disposed at a top end of said combustion chamber;   a plenum housing defining a plenum chamber that receives said combustion chamber and that has a top end extending above said top end of said combustion chamber, a bottom end extending below said combustion chamber, an air inlet provided in a space between said top end of said combustion chamber and said top end of said plenum chamber and having an open end adapted for communication with ambient air, and an air outlet proximate to said bottom end of said plenum chamber;   a heat exchanger defining a heat exchanger chamber disposed on one side of said combustion chamber and having a top end lower than said top end of said plenum chamber, an air inlet disposed in one side of said heat exchanger chamber proximate to said combustion chamber and communicated fluidly with said air outlet of said plenum chamber, an air outlet proximate to said top end of said heat exchanger chamber and disposed in the other side of said heat exchanger chamber opposite to said combustion chamber, and a gas inlet and a gas outlet both of which are disposed at said top end of said heat exchanger chamber, said heat exchanger chamber further having a tube-bundled structure disposed in said heat exchanger chamber and having a plurality of exhaust tubes each of which defines a passageway that connects to and that extends downward from said gas inlet of said heat exchanger chamber and turns upward at a bottom end of said heat exchanger chamber to connect to said gas outlet of said heat exchanger chamber; and   a manifold extending above said combustion chamber and said heat exchanger chamber, and extending through said air inlet of said plenum chamber, said manifold having one end connected to said gas outlet of said combustion chamber and the other end extending through said open end of said air inlet of said plenum chamber and connected to said gas inlet of said heat exchanger chamber.   
   
   
       5 . The combustion system of  claim 4 , wherein said heat exchanger further has a plurality of baffles dividing said heat exchanger chamber into a plurality of sections which are connected to form a tortuous path extending between said air inlet and said air outlet of said heat exchanger chamber.