Abstract: A valve assembly for detecting leaks in a fluid system which includes an air-tight liquid chamber defined by a transparent sleeve enclosed within a removable cap having windows formed therebetween, the chamber being at least partially filled with liquid, and a plunger means provided with an orifice, including a tube means arranged to communicate between said orifice and liquid within the liquid chamber, wherein the lower end of the tube means is provided with a restraining and sealing means, whereby the upward movement is restricted thereby, and the liquid chamber is sealed during the open mode of the valve. The terminating end of the tube is formed having a beveled tip to allow ease of fluid discharge therefrom. The valve assembly is connected to the fluid line so as to allow the fluid to pass therethrough unimpeded.

Abstract: A valve assembly for detecting leaks in fluid systems which includes an airtight transparent cup means at least partially filled with liquid and a plunger means provided with an orifice and a tube means interconnecting said orifice and liquid. The valve assembly is connected into the fluid line so as to allow the fluid to pass therethrough unimpeded. Depression of the plunger effectively closes the fluid line except for the passageway afforded by the orifice and the tube positioned in the liquid. The existence of a leak in the fluid system is thereby easily observed by a fluid flow through the liquid, i.e., bubbles, etc.