September 15, 2000


A multi-zone, single-gas, tracer gas decay measurement technique was used to test the ventilation systems of a single-story, slab-on-grade 1350 sq. ft. house in Las Vegas, Nevada, and a two-story, 3192 sq. ft. house with basement in Minneapolis, Minnesota. Some of the systems were independent of the central air distribution system, while others were integrated with it. In general, results showed that all ventilation systems benefitted from periodic operation of the central fan, giving excellent uniformity of ventilation air distribution. System without central fan recirculation showed poor ventilation air distribution for closed rooms where there was no ventilation system duct. This article was first published in ASHRAE Transactions 2000, Vol. 106, Part 2. Reprinted with permission.