Method and apparatus for draining condensate from a gas water heater exhaust system

Abstract

A method and apparatus for conveying condensate from an exhaust system of a gas water heater to a drain. The method includes the steps of operating the gas water heater to produce products of combustion, operating a blower to cause the products of combustion to flow through the exhaust system to atmosphere, allowing condensate from the products of combustion to form within the exhaust system, using a drain conduit to connect a relatively high pressure zone of the exhaust system to a relatively low pressure zone of the exhaust system, using a pressure differential between the relatively high pressure zone and the relatively low pressure zone to convey condensate through the drain conduit from the relatively high pressure zone to the relatively low pressure zone, and conveying condensate from the relatively low pressure zone to the drain.

1 . A method of conveying condensate from an exhaust system of a gas water heater to a drain, the method comprising:
 operating the gas water heater to produce products of combustion;   connecting an exhaust outlet of the gas water heater to the exhaust system such that the exhaust system receives the products of combustion;   operating a blower to cause the products of combustion to flow through the exhaust system to atmosphere;   allowing condensate from the products of combustion to form within the exhaust system;   using a drain conduit to connect a relatively high pressure zone of the exhaust system to a relatively low pressure zone of the exhaust system, the relatively low pressure zone between the exhaust outlet and the blower and the relatively high pressure zone downstream of the relatively low pressure zone;   using a pressure differential between the relatively high pressure zone and the relatively low pressure zone to convey condensate through the drain conduit from the relatively high pressure zone to the relatively low pressure zone; and   conveying condensate from the relatively low pressure zone to the drain.   
     
     
         2 . The method of  claim 1 , wherein the relatively high pressure zone is located at the blower. 
     
     
         3 . The method of  claim 1 , wherein the relatively high pressure zone is located downstream of the blower. 
     
     
         4 . The method of  claim 1 , further comprising:
 conveying condensate from the relatively low pressure zone to the drain at least in part due to gravity.   
     
     
         5 . The method of  claim 1 , further comprising:
 using a second drain conduit to connected a second relatively high pressure zone of the exhaust system to the relatively low pressure zone; and   using a second pressure differential between the second relatively high pressure zone and the relatively low pressure zone to convey condensate through the second drain conduit from the second relatively high pressure zone to the relatively low pressure zone.   
     
     
         6 . A gas water heater comprising:
 a storage tank for storing water;   a combustion chamber;   a burner positioned in the combustion chamber, the burner for producing products of combustion;   a heat exchanger positioned in the storage tank for receiving the products of combustion from the combustion chamber and for transferring heat from the products of combustion to the water stored in the storage tank, the heat exchanger including an outlet that extends from the storage tank; and   an exhaust system including a first exhaust conduit connected to the outlet to receive the products of combustion from the heat exchanger, a second exhaust conduit fluidly connected to atmosphere, a blower connected between the first exhaust conduit and the second exhaust conduit with the first exhaust conduit upstream of the blower and the second exhaust conduit downstream of the blower, a first drain fitting in the first exhaust conduit between the outlet and the blower and a second drain fitting downstream of the first drain fitting such that the first drain fitting is at a first pressure and the second drain fitting is at second pressure, the second pressure greater than the first pressure, and a drain conduit connected between the first drain fitting and the second drain fitting such that the difference between the second pressure and the first pressure causes condensate from the products of combustion to flow through the drain conduit from the second drain fitting to the first drain fitting.   
     
     
         7 . The gas water heater of  claim 6  wherein the first exhaust conduit further includes a vertical portion and the first drain fitting is located on the vertical portion. 
     
     
         8 . The gas water heater of  claim 7  wherein the first drain fitting is located adjacent to the top of the storage tank. 
     
     
         9 . The gas water heater of  claim 8  wherein the blower includes the second drain fitting. 
     
     
         10 . The gas water heater of  claim 9 , wherein the blower is located above the storage tank. 
     
     
         11 . The gas water heater of  claim 10 , further comprising:
 a trap connected to the first exhaust conduit and positioned below the outlet of the heat exchanger; and   a second drain conduit connected to the trap, the second drain conduit for conveying condensate to a drain.   
     
     
         12 . The gas water heater of  claim 8  wherein the second drain fitting is located downstream of the blower. 
     
     
         13 . The gas water heater of  claim 12 , wherein the blower is located above the storage tank. 
     
     
         14 . The gas water heater of  claim 13 , further comprising:
 a trap connected to the first exhaust conduit and positioned below the outlet of the heat exchanger; and   a second drain conduit connected to the trap, the second drain conduit for conveying condensate to a drain.   
     
     
         15 . The gas water heater of  claim 6  wherein the blower includes the second drain fitting. 
     
     
         16 . The gas water heater of  claim 15 , wherein the blower is located above the storage tank. 
     
     
         17 . The gas water heater of  claim 6  wherein the second drain fitting is located downstream of the blower. 
     
     
         18 . The gas water heater of  claim 17 , wherein the blower is located above the storage tank. 
     
     
         19 . The gas water heater of  claim 7 , wherein the blower is located above the storage tank. 
     
     
         20 . The gas water heater of  claim 7 , further comprising:
 a trap connected to the first exhaust conduit and positioned below the outlet of the heat exchanger; and   a second drain conduit connected to the trap, the second drain conduit for conveying condensate to a drain.