Patent ID: 7516649

Claim:
A system for determining “real time” air leakage from a duct in fluid communication with an enclosure, wherein the duct has an inlet and an outlet in fluid communication with the enclosure, said system comprising: a duct fan positioned between the duct inlet and the duct outlet and operated in an “on” condition for generating an airflow through the duct; a base fan in fluid communication with the enclosure for selectively creating an overpressure (+) in the enclosure and, alternatively, an under pressure (−) in the enclosure, when said base fan is “on”; and an airflow meter for measuring a return airflow through the duct inlet, f r , and a supply airflow through the duct outlet, f s , under an initial condition wherein said duct fan is “on” and said base fan is “off” (f r and f s ), and for measuring a return airflow through the duct inlet, f r± , and a supply airflow through the duct outlet, f s± , under a condition wherein said duct fan is “on” and said base fan is “on” (f r± and f s± ), to identify a substantially leak-free duct when, approximately, f s =f r and f r± =f s± , respectively.