Flexible HVAC duct and method of use

Abstract

A flexible HVAC duct is made with a support structure-containing duct liner, insulation layer, and reinforcing layer-containing vapor barrier. At least the duct liner and vapor barrier are constructed of polymer materials that enable them to be placed in the same recycling stream once the flexible HVAC duct is removed from its installed location. The insulation layer can also be made of a polymer material compatible with that used for the duct liner and vapor barrier so that the entire duct can be recycled once removed.

1 . In a flexible HVAC duct comprising a duct liner, a layer of insulation surrounding the duct liner, and a vapor barrier surrounding the layer of insulation, the improvement comprising:
 a) the duct liner further comprising a first polymer layer, a second polymer support structure, and means for connecting the first polymer layer and the second polymer support structure together so as to form a generally cylindrical configuration; and   b) the vapor barrier further comprising a third polymer layer, a fourth polymer reinforcing layer, and means for connecting the third polymer layer and the fourth polymer layer together;   c) wherein the polymers used in the duct liner and the polymers used in the vapor barrier are the same or similar in nature so that the duct liner and vapor barrier can be recycled together once the flexible HVAC duct is removed from an installed location.   
     
     
         2 . The duct of  claim 1 , wherein the insulation is made of a polymer material the same or similar to that used in the duct liner and vapor barrier so that the entire duct can be recycled. 
     
     
         3 . The duct of  claim 1 , wherein the polymer used in the duct liner and the vapor barrier is one of polypropylene, polyethylene, polyester, polyvinyl chloride, and a chlorinated polyethylene. 
     
     
         4 . The duct of  claim 2 , wherein the polymer used in the duct liner, the insulation, and the vapor barrier is one of polypropylene, polyethylene, polyester, polyvinyl chloride, and a chlorinated polyethylene. 
     
     
         5 . The duct of  claim 1 , wherein the second polymer support structure is helical in shape. 
     
     
         6 . The duct of  claim 1 , wherein the connecting means for the duct liner comprises an adhesive or a fifth polymer layer, with the second polymer support structure disposed between the first and fifth polymer layers. 
     
     
         7 . The duct of  claim 2 , wherein the connecting means for the duct liner comprises an adhesive or a fifth polymer layer, with the second polymer support structure disposed between the first and fifth polymer layers. 
     
     
         8 . The duct of  claim 1 , wherein the connecting means for the vapor barrier comprises an adhesive or a sixth polymer layer, with the fourth polymer reinforcing layer disposed between the third and sixth polymer layers. 
     
     
         9 . The duct of  claim 2 , wherein the connecting means for the vapor barrier comprises an adhesive or a sixth polymer layer, with the fourth polymer reinforcing layer disposed between the third and sixth polymer layers. 
     
     
         10 . A method of recycling the flexible HVAC duct of  claim 1  installed in a structure comprising:
 b) removing the duct from the structure; and   c) separating the duct liner and vapor barrier from the insulation layer to form a recyclable load as the vapor barrier and the duct liner.   
     
     
         11 . A method of recycling the flexible HVAC duct of  claim 2  installed in a structure comprising removing the duct from the structure to form a recyclable load as the duct liner, the insulation layer, and the vapor barrier for recycling instead of disposal. 
     
     
         12 . In a method of supplying a gas to a location in a structure using a flexible HVAC duct, the improvement comprising using the duct of  claim 1  for the supplying step. 
     
     
         13 . The method of  claim 12 , wherein the gas is heater or cooled or conditioned air.