air ad-mit-tance valve
Air, Admittance, Valve
A device that allows air to enter a plumbing system to balance the pressure.
Example usage: I installed an Air Admittance Valve in the bathroom.
Most used in: North America and the United Kingdom.
Most used by: Plumbers, builders, and other tradespeople.
Popularity: 8/10
Comedy Value: 3/10
Also see: AAV, Automatic Air Vent, In-Line Vent, One-Way Air Valve,
What is an Air Admittance Valve?
An air admittance valve, also known as an AAV or auto-vent, is a plumbing fitting commonly used in drain, waste and vent systems. It is a one-way valve that allows air to enter the drainage system, but prevents sewer gases from escaping back into the home. Air admittance valves are a cost-effective and safe alternative to traditional venting.
AAVs are typically installed in locations where traditional venting is not possible, such as high-rise buildings, or where it is not practical, such as in a basement bathroom. They are most often used in conjunction with a sink, tub, or toilet, and can be installed in the drain line itself, or in the wall near the fixture.
According to the Plumbing-Heating-Cooling Contractors Association, the use of air admittance valves has increased significantly in recent years. In the United States, AAVs are now used in over 60% of all new construction projects, and in some areas they are required by code.
Air admittance valves are a safe, reliable, and cost-effective way to vent a drainage system. They offer a number of advantages over traditional venting, including easier installation, fewer required materials, and reduced labor costs.
The Origin of the Term: Air Admittance Valve
The term 'Air Admittance Valve' (AAV) first appeared in the plumbing industry in the United States in the late 1980s. It was initially developed as an alternative to costly and time consuming traditional venting systems.
The AAV is a one-way valve that allows air to enter the drainage system when a negative pressure is created. This helps to prevent the siphoning of water from traps and maintains the flow of the drainage system. The AAV also helps to reduce noise from the system.
The AAV quickly became popular among plumbers and is now a standard component of most plumbing systems. It is used in many countries and is an essential part of the plumbing infrastructure.
