1-1/2" ABS Sch 40 Adapter Air Admittance Valve 392279

Features

• An air admittance valve shall be acceptable as a vent termination for any individual vent, common vent, circuit vent, loop vent, island fixture vent, vent stack or stack vent to prevent siphonage of a fixture trap
• The purpose of an air admittance valve is to provide a method of allowing air to enter the plumbing drainage system without the use of a vent extended to open air and to prevent sewer gases from escaping into the building
• An air admittance valve is a one-way valve designed to allow air to enter the plumbing drainage system when negative pressures develop in the piping system
• The device shall close by gravity and seal the vent terminal at zero differential pressure (no flow conditions) and under positive internal pressures
• Unique technology opens at -0.01 Psi and seals at 0 psi and above