A valve apparatus is disclosed for use in regulating the flow of fluid between a closed hydraulic loop and a fluid source in a hydraulic circuit, where the valve apparatus provides up to four different functions including a check valve, a neutral valve, a relief valve and a pressure rise rate valve. The apparatus includes a valve seat for selectively permitting fluid communication between the closed hydraulic loop and the fluid source, a sleeve member and a relief poppet in the valve seat, a relief compression spring inside the sleeve and positioned adjacent the relief poppet and the base of the slidable member, a valve guide and an accumulator piston slidably mounted within the valve guide to define an accumulator volume therein.

 
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