If the HSI ohm reading is infinite

The 93W72 and 93W7201 are interchangeable across all Lennox HVAC applications

What is the purpose of the 3-inch insertion length

For wash-down areas

The 50/60 Hz compatibility and 2

Reznor 205882 Vent Kit 320788-704 If the HSI ohm readingThe Reznor 205882 Vent Kit is a critical component for completing a concentric vent installation on high efficiency Reznor CAUA gas fired heaters. Specifically engineered for CAUA 150 and 200 models, this CC6 horizontal vent kit facilitates the proper intake of combustion air while safely exhausting flue gases through a single wall penetration. The 6 inch concentric configuration eliminates the need for multiple holes in the building envelope,