Measurement of Return Leaks in Residential Buildings in North Louisiana

Heating ventilation and air conditioning (HVAC) duct leaks in residential buildings can occur both at the supply side and the return side of the duct system. The objective of this study is to develop a methodology to measure return duct leakage at the actual HVAC system operating pressure. Two techniques are developed and field studies are performed to measure return leakage in residential homes. The weighted-average return leakage in residential homes in North Louisiana is determined to be 58L/s (116 ft3/min) and the weighted-average equivalent orifice leakage area is determined to be 0.018 m2 (28.5 in.2). The weighted flow exponent of return leakage is determined to be 0.55.