The Lochinvar & A.O. Smith 100145006 Combustion Fan Assembly is a replacement airflow component designed for compatible Lochinvar boilers and A.O. Smith gas-fired water heating systems. It supplies the combustion chamber with the proper amount of air and assists in venting combustion gases for safe, efficient burner operation. By maintaining consistent airflow, it supports reliable ig... https://www.partshnc.com/combustion-fan-assembly-5