Rheem-Ruud RTG20151D-1 Water Heater Concentric Straight Vent 3"/5"

The Rheem-Ruud RTG20151D-1 is also a Concentric Straight Vent, which is designed to be used only for venting gasoline and propane water heaters only. This crucialsafety feature, double-wall construction effectively expels combustion products while at the same time offering safe air inlet. It is in fact a double barrelled vent consisting of two circular tubes. The exhaust gasses are channeled through the inner pipe from the water heater and gets to as high as 170°F at some point. The outer pipe is used for drawing fresh air for burning hence making it safe and effective in its venting system.