The Navien 30020992B Fan Assembly is a genuine OEM component designed to provide proper airflow for combustion in compatible Navien heating equipment. It is used in select Navien NEFB-C combi boilers and related compatible models. The fan moves combustion air through the system, helping maintain the correct air supply for stable and efficient burner operation. This replacement assembl... https://www.partshnc.com/30020992b-navien-tankless-water-heaters-fan-assembly