Fuente: WIPO "wine" A fuel oil supply system comprising a fuel oil tank mounted on legs or other supporting means elevated sufficiently to provide a gravity flow of fuel to an oil burner, the tank having a threaded outlet at the bottom portion thereof, an outlet valve comprising a Y-shaped body portion having an externally threaded main body portion serving as an inlet and two angularly disposed leg portions, one serving as an outlet for the fuel and the other as a housing for a valve stem. In the inlet of the fuel valve a short nipple is inserted so that when the modified valve unit is screwed into the outlet of the fuel tank, a sump is formed in which any water and other foreign matter present in the fuel will be collected. Oil for the burner is withdrawn several inches above the bottom portion of the tank, is relatively free of condensed moisture and other foreign matter, so that a continuous flow of oil to the burner is assured even at temperatures below freezing.