These valves begin opening at the set vacuum level and fully open at about 10% over the set point. They begin closing as the vacuum level drops and fully close when the system is restored below the set point. Adjust the set vacuum level within the range. Valves have a vented relief port to exhaust discharge directly.

No need to vent your plumbing to the outdoors—these valves allow air into your drain, waste, and vent system. When wastewater drains, it creates negative pressure, which opens these valves. When water isn’t draining, they close to prevent sewer gas from escaping. To install, cement the plastic body to your vent pipe. They come as two pieces that thread together. Unthread the pieces to access your vent pipe or for cleaning.

Stop backward flow in outdoor faucets with garden hose outlets. This valve drains when closed to prevent freezing. To prevent tampering, tighten the set screw until the head breaks off.

Rated for 12 times the pressure of standard vacuum-breaking valves, these can handle up to 1,500 psi. Also known as vacuum-breaking valves, they have vents that open when pressure drops to relieve vacuum conditions and prevent backward suction from drawing liquid into upstream piping. Body is 316 stainless steel for excellent corrosion resistance.

Prevent dirty, contaminated water from backing up into your garden hose line—install these vacuum breakers between a faucet and a garden hose. Also known as vacuum-breaking valves, these valves have a built-in check valve that blocks backflow, so you can leave your hose in a utility sink full of dirty water without the water going back into the line.

When the check valve is closed, it has vents that open to release the water. This reduces pressure in the line and confirms the valve is working. Because these valves vent water, use them in environments where spilled water won’t cause a problem. This design adheres to ASSE Standard 1011 for valves with a vent.

Mount valves to faucet outlets with a set screw, and easily thread or unthread a hose while the valves stay in place.

Valves comply with Uniform Plumbing Code (UPC) and are CSA certified, so they're safe to use in sanitary plumbing systems because they prevent contamination from flowing backward into your line.

These valves are designed to be used intermittently. They've been tested under ASME A112.1.3, which assumes the valves will not be used for more than 12 hours at a time.