If installing for wood stove insert or freestanding stove, use RS 9 for flue sizes up to 144 square inches (this is for usage with doors closed). If doors are left open during usage, or area is greater than 144 square inches, use RS 12.
NOTE: The black background indicates the fan will most likely create some air-flow noise due to high air velocity in the chimney. The light grey background indicates the fan base will not cover the chimney opening and a special adapter muse be used. Please call us for ordering adapters, speed control, or wireless control.