This piloted discharge check valve is a combination of a pilot valve, a pressure discharge valve, and check valve in one complete piece to make a constant run air compressor with gas engine or electric motor. This check valve combo is made by Conrader in the United States and is an ng series valve. This valve is equipped with an in-line check valve and attached to the side is a built-in piloted unloader valve set to 145-175 psi. There is a muffler on the exhaust air port to quiet down the unloaded air that is released once the compressor reaches 175 psi. On top there is a 1/4" fnpt port for a relief valve and on the back of the valve there is a 1/8" Female npt port that controls the throttle on a gas engine and/or unloader valves on some pumps.
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