An apparatus to allow or stop an air flow into an enclosed environment or piping system comprises (a) a housing, (b) a first valve seat, (c) a first sealing member, (d) a second valve seat, (e) a second sealing member, (f) at least one locking mechanism configured to limit a movement of the first sealing member and/or the second sealing member; wherein the first sealing member moves away from the first valve seat when the second pressure is greater than the first pressure in a predetermined pressure difference; wherein the second sealing member moves away from the first valve seat when the third pressure is greater than the second pressure in a predetermined pressure difference; wherein the first pressure communicates with a system pressure in the piping system; and wherein the third pressure communicates with an ambient air pressure.

Afoot valve assembly according to the present invention includes: an adapter attached to a lower opening end of a pump column configured to accommodate a pump configured to be submerged in a handling liquid, the adapter accommodating a suction port of the pump; a disc-shaped valve disc including a flow path defining surface that is located below a lower end surface of the adapter and defines an inflow path allowing the handling liquid to flow into the pump between the surfaces, the valve disc opening and closing a lower opening of the adapter; a biasing member biasing the valve disc toward the adapter; and a one-way valve disposed in the inflow path, the valve opening for fluid discharged from the lower opening depending on a pressure of the fluid and closing for the handling liquid flowing toward the lower opening when the valve disc is closed.

A check cover assembly for a backflow prevention assembly having a body defining an interior housing a test cock. The check cover assembly includes a ball with a central aperture and a complementary groove in an outer circumference of the ball as well as a base including a shroud portion housing the ball to create a ball valve. The shroud portion defines an access gap for accessing an actuation feature slot with a landkey of the ball valve and a threaded opening. A coupling is attached to the threaded opening in fluid communication with the interior for connecting to testing equipment. The actuation feature is used to open and close the ball valve.

A backflow prevention assembly has a body having a first bucket with a sidewall extending between a closed end and an open end along a first bucket axis, a first conduit extending from an inlet of the sidewall of the first bucket, and a second bucket having a sidewall extending between a closed end and an open end along a second bucket axis. A second conduit extends between an outlet of the sidewall of the first bucket and an inlet of the sidewall of the second bucket, and a third conduit extends from an outlet of the sidewall of the second bucket. The conduits extend along a conduit axis that is perpendicular to the bucket axes. The valve assembly includes covers secured over the open ends of the buckets and a valve member located in each bucket that is biased to prevent reverse flow through the inlets of the buckets.

A check valve for a backflow prevention assembly includes a linkage with a platform having a proximal end and a distal end and a first coupling member supported by the platform for engaging a bias assembly. A stop protrudes from the proximal end of the platform to engage a frame of the check valve for limiting travel of the platform. A branch depends from the proximal end of the platform, the branch having a hinge pin configured to nest in a slot defined by check valve. A second coupling member depends from the distal end of the platform for engaging a valve member.

A valve assembly with a spring retention assembly including an elongated cylinder portion having an open threaded end and a closed end and an elongated piston portion having a free end and a threaded tab end configured to thread through the open threaded end and, thereby, be slideably captured in the cylinder portion. A spring couples to the body portion and the piston portion to provide a force to urge the body portion and the piston away from one another, wherein the closed end and the free end are similarly shaped so that the spring retention assembly can be reversibly mounted to a valve member that can also be reversibly mounted.

A pressure vent valve for ventilation of the interior of a motor vehicle, with a frame with at least one sealing surface and with at least one flexible valve flap mounted on the frame. In an idle position, the valve flap assembly abuts the sealing surface to prevent airflow through the pressure vent valve. When a sufficient pressure occurs, the valve flap assembly assumes an open position lifted from the sealing surface to allow airflow through the pressure vent valve. The pressure vent valve further includes an installation indicator formed in or on the frame to ensure alignment during installation.

A venting valve for venting the interior of a vehicle includes a housing having at least one passage opening, and at least one venting flap which is mounted on the housing by a pivot mounting so as to be pivotable between a closed position and an open position. In the closed position, the at least one venting flap closes off the at least one passage opening and, in the open position, opens up the at least one passage opening for an air stream from the interior of the vehicle to the outside. The pivot mounting is arranged on an inner side of the housing, which inner side, in the assembled or installed state, faces the interior of the vehicle.

A valve assembly with a spring retention assembly including an elongated cylinder portion having an open threaded end and a closed end and an elongated piston portion having a free end and a threaded tab end configured to thread through the open threaded end and, thereby, be slideably captured in the cylinder portion. A spring couples to the body portion and the piston portion to provide a force to urge the body portion and the piston away from one another, wherein the closed end and the free end are similarly shaped so that the spring retention assembly can be reversibly mounted to a valve member that can also be reversibly mounted.

A riser manifold assembly includes a control valve, a first spool pipe, a flow control switch, a check valve, a second spool pipe, and a test and drain valve. An inlet of the first spool pipe being mechanically coupled and fluidly sealed with an outlet of the control valve. The flow control switch being mechanically mounted to the first spool pipe. An inlet of the check valve being mechanically coupled and fluidly sealed with an outlet of the first spool pipe. An inlet of the second spool pipe being mechanically coupled and fluidly sealed with an outlet of the check valve. The test and drain valve being mechanically coupled and fluidly sealed with an auxiliary port of the second spool pipe.