Leakage of ducted air terminal connections : part 2, experimental esults

Leakage data for ducted air terminal connections are reported. The leakage flow rate generally varied from 1% to 8% of the total approach flow rate. Leakage was found to increase with the increase in the static pressure adjacent to the terminal for the unsealed condition. With marginal sealing of rigid ducts, leakage was found to be less than half that of the unsealed connection. The use of drawbands to mount air terminals to flexible ducts can reduce leakage at the collar to virtually
zero. The application of a gasket to rectangular supply or return grilles is recommended as a means of reducing leakage.