A new test procedure for determining capture efficiency (CE) of domestic range hoods (ASTM-E3087.18) was used to investigate how the range hood mounting height above a stove influences CE. Previous studies on CE utilized only two heights for a single range hood and a test procedure that did not strictly adhere to ASTM-E3087.18. In the study reported herein, testing was performed in accordance with ASTM-E3087.18 on six range hoods of similar design at three heights. The measured CE values ranged from 42.8–96.2%CE with CE changing by 8.2%CE at worst when varying the height for a specific fan. The influence of mounting height on CE uncertainty, repeatability, reproducibility and variability were also investigated. Lower mounting heights were found to increase CE and reduce uncertainty at the cost of increased variability between repeat tests. In contrast, intermediate mounting heights typically improved variability performance and repeatability/reproducibility. One range hood with vents for re-circulation showed higher uncertainty and more variability, indicating that flow exhausting from these vents can influence CE performance. Thus, it is possible that future ASHRAE/HVI certification standards be written with re-circulating vents sealed off during testing and a specified mounting height to minimize variations in CE caused by varying mounting heights.

一种用于确定家用抽油烟机的捕获效率（CE）的新测试程序（ASTM-E3087.18）被用于研究灶具上方的抽油烟机安装高度如何影响CE。先前对CE的研究仅针对单个抽油烟机使用了两种高度，并且没有严格遵守ASTM-E3087.18的测试程序。在本文报道的研究中，根据ASTM-E3087.18在六个高度相似的六个抽油烟机上对三个高度进行了测试。当改变特定风扇的高度时，测得的CE值范围为42.8–96.2％CE，最差的情况下，CE会改变8.2％CE。还研究了安装高度对CE不确定性，重复性，再现性和可变性的影响。发现较低的安装高度会增加CE并减少不确定性，但代价是重复测试之间的差异会增加。相反，中间安装高度通常会提高可变性性能和可重复性/可再现性。具有排气孔以进行再循环的一种抽油烟机显示出更高的不确定性和更大的可变性，表明从这些排气孔排出的气流会影响CE性能。因此，将来的ASHRAE / HVI认证标准可能会写成在测试过程中密封的再循环通风孔和规定的安装高度，以最大程度地减少因安装高度变化而引起的CE变化。