Description AUTOMATIC AIR ADMITTANCE VALVE Type* AUTOMATIC AIR ADMITTANCE Nominal size* 82 x 110 mm Mat, body* ABS PLASTIC Colour WHITE Volume 3.742 cdm Weight 0.354 kg Manufacturer Old Part Number 153.3.4W Manufacturer WAVIN – POLYPIPE CIVILS Manufacturer Part Number 4S304W An Air Admittance Valve (AAV), also known as a Durgo valve or a Studor vent, is a one-way valve used in plumbing systems to allow air to enter a drainage system when negative pressure occurs, preventing siphonage and the associated release of sewer gases. It effectively replaces traditional vent stacks, particularly in situations where extending a vent pipe to the roof is impractical or undesirable.
