AIR INTAKE COUPLING WITH NOISE SUPPRESSION FOR LOW NOx EMISSION FURNACE

Abstract

An air intake coupling has at least one noise suppression hole formed therein. A gas-air mixer elbow is fluidly coupled to the air intake coupling. A burner box assembly is fluidly coupled to the gas-air mixer elbow via a gas-air plenum box. A heat-exchange tube has a first end that is fluidly coupled to the burner box assembly. A fan is fluidly coupled to a second end of the heat-exchange tube via a cold-end header box.

1 . A furnace comprising;
 an air intake coupling, the air intake coupling having at least one noise suppression hole formed therein, the air intake coupling comprises a first tubular section and a second tubular section;   a gas-air mixer elbow fluidly coupled to the air intake coupling, wherein the gas-air mixer elbow is configured to mix fuel with atmospheric air supplied through the air intake coupling;   a burner box assembly fluidly coupled to the gas-air mixer elbow via a gas-air plenum box;   a heat-exchange tube having a first end fluidly coupled to the burner box assembly;   a fan fluidly coupled to a second end of the heat-exchange tube via a cold-end header box; and   a pressure tap extruded from the first tubular section.   
     
     
         2 . The furnace of  claim 1 , wherein a diameter of the first tubular section is larger than a diameter of the second tubular section 
     
     
         3 . The furnace of  claim 1 , wherein the first tubular section and the second tubular section are integral to each other. 
     
     
         4 . The furnace of  claim 1 , wherein the at least one noise suppression hole comprises a first noise suppression hole and a second noise suppression hole formed on opposite sides of the second tubular section. 
     
     
         5 . The furnace of  claim 4 , wherein the first noise suppression hole is formed on opposite sides of the second tubular section approximately 180 degrees from the second noise suppression hole. 
     
     
         6 . The furnace of  claim 5 , wherein the first noise suppression hole and the second noise suppression hole are formed via a single drilling operation. 
     
     
         7 . The furnace of  claim 1 , wherein the at least one noise suppression hole prevents leakage of more than approximately 8% of air drawn into the air intake coupling. 
     
     
         8 . The furnace of  claim 1 , wherein the at least one noise suppression hole comprises a diameter of approximately 0.188 inches. 
     
     
         9 . The furnace of  claim 1 , wherein the first tubular section and the second tubular section each comprise a circular cross-section; 
     
     
         10 . The furnace of  claim 1 , comprising a flange formed on an end of the first tubular section on a side opposite the second tubular section. 
     
     
         11 . The furnace of  claim 1 , wherein the first noise suppression hole is aligned with the pressure tap. 
     
     
         12 . A furnace comprising;
 an air intake coupling, the air intake coupling having at least one noise suppression hole formed therein, the air intake coupling comprises a first tubular section and a second tubular section;   a gas-air mixer elbow fluidly coupled to the air intake coupling;   a burner box assembly fluidly coupled to the gas-air mixer elbow via a gas-air plenum box;   a heat-exchange tube having a first end fluidly coupled to the burner box assembly;   a fan fluidly coupled to a second end of the heat-exchange tube via a cold-end header box; and   a flange formed on an end of the first tubular section on a side opposite the second tubular section.   
     
     
         13 . The furnace of  claim 12 , wherein the first tubular section and the second tubular section are integral to each other. 
     
     
         14 . The furnace of  claim 12 , wherein the at least one noise suppression hole comprises a first noise suppression hole and a second noise suppression hole formed on opposite sides of the second tubular section. 
     
     
         15 . The furnace of  claim 14 , wherein the first noise suppression hole is formed on opposite sides of the second tubular section approximately 180 degrees from the second noise suppression hole. 
     
     
         16 . The furnace of  claim 15 , wherein the first noise suppression hole and the second noise suppression hole are formed via a single drilling operation. 
     
     
         17 . The furnace of  claim 12 , wherein the at least one noise suppression hole prevents leakage of more than approximately 8% of air drawn into the air intake coupling. 
     
     
         18 . The furnace of  claim 12 , wherein the at least one noise suppression hole comprises a diameter of approximately 0.188 inches. 
     
     
         19 . The furnace of  claim 12 , comprising a pressure tap formed in the first tubular section, wherein the at least one noise suppression hole is in line with the pressure tap. 
     
     
         20 . A method of manufacturing a furnace, the method comprising:
 forming a tubular air intake coupling, the air intake coupling comprises a first tubular section and a second tubular section;   forming a plurality of noise suppression holes on opposite sides of the second tubular section of the air intake coupling;   forming a pressure tap in the first tubular section, wherein a first noise suppression hole of the plurality of noise suppression holes is in line with the pressure tap;
 fluidly coupling the air intake coupling to a gas-air mixer elbow; 
   fluidly coupling the gas-air mixer elbow to a burner box assembly via a gas-air plenum box;   fluidly coupling a first end of a heat-exchange tube to the burner box assembly; and   fluidly coupling a second end of the heat-exchange tube to a fan via a cold-end header box.