In a triple-wide manufactured home, Lubliner has installed a bathroom exhaust fan that pulls air through wall cracks and passive intakes at each window. In a separate system, he has installed an outside air duct, which is connected to a furnace blower. The duct allows the blower to draw in a small amount of outside air, which it circulates throughout the house. It assures a very even distribution, since the air is sent to all areas of the home through the heating ducts. Using trace gasses pulled in by both systems, Lubliner plans to measure the amount of outside air each pulls into rooms throughout the home.
Disadvantages exist with both systems.
Exhaust fans can not distribute air as evenly as duct-blower systems, according to Lubliner. An exhaust fan uses about 20 watts, Lubliner said. In homes with ducts built into floors, duct-blower systems would inject cold air into a room during the winter. When you mix these two streams of air and deliver it at someone's feet, you're going to have comfort problems. It puddles cold air at your feet.