A-25 Study of the Drainage Performance Improvement Technique of Drainage Stack System by means of Air Admittance Valves : Part4. An application of the double Air-Admittance Valves to the horizontal fixture branch

Abstract

This report uses the evaluation indices acquired by measuring a pipe pressure variation and an air flow rate when air-admittance valves were installed in two locations along the horizontal fixture drain branch of a drainage stack system. And examines how the change of the negative pressure value and the positive pressure value of pipe pressure affects the drainage performance when the number of locations for installing air-admittance valves is increased.