Seminar 75--Solving Duct System Performance Problems: Acoustics Effects, Air Leakage and Capture Hood Flow Measurement

This product is a zip file that contains files that consist of PowerPoint slides synchronized with the audio-recording of the speaker, PDF files of the slides, and audio only (mp3 format) as noted.

This seminar discusses three different performance metrics for duct systems, including the influence of acoustics on duct design, simplified low-cost identification of duct leakage and accurate diffuser flow measurement with capture hoods. Affordable ways to comply with ASHRAE's background noise recommendations are presented, as will a low-cost duct leakage measurement based on temperature and humidity. Field test results and comparisons with fan-pressurization testing are presented. The lack of a universally accepted calibration standard for flow capture hoods is discussed, and guidance for measurement practices when using capture hoods for residential or commercial systems is presented.

1. Acoustics Considerations in Duct Design: Will It be Too Annoying in the Room?
Jeff Boldt, P.E., HBDP, Fellow ASHRAE, IMEG Corp, Madison, WI

2. A Novel Duct Leakage Measurement Technique Based on Relative Humidity Measurement
Mark Modera, Ph.D., P.E., Fellow ASHRAE, University of California, Davis, CA

3. Accuracy of Residential Capture Hoods
Steven Rogers, Member, The Energy Conservatory, Minneapolis, MN

4. Capture Hood Errors Associated with Commercial Diffuser Types
Robert Moss, Member, Dwyer Instruments, Michigan City, IN