Whole-house fans are installed in a central hallway inside the house and pull fresh outdoor air through open windows. They are often used to augment air conditioning or instead of air conditioning in mild summertime climates.
Benefits of Whole-House Fans:
- Efficient, cost-effective cooling
- Can cut summer air conditioning costs and create a more comfortable living environment
- Exchange air much more rapidly than air conditioning units, allowing faster cooling of the interior
- Draw cooler air indoors, especially when used at night and early morning hours
- Extract heat from objects within a house, such as appliances, furniture and walls
Thanks to a motor mounted just above and to the side of the fan, a belt-drive whole-house fan provides for smooth, quiet operation.
Direct drive whole-house fans are easy to install since no attic joists need to be cut. They feature a pull chain for easy operation.
- For maximum effectiveness, a whole-house fan must be sized correctly for the structure it is required to ventilate.
- The formula to follow for determining capacity is: square feet of living area x 3 = CFM (cubic feet of air moved per minute) required.
- Because whole-house fans exhaust hot air into an attic, a properly sized attic ventilation system is required to exhaust heated air from the attic to outdoors.
- To determine the net free area of attic ventilation required, use the following formula: CFM rating of fan divided by 750 = square feet of net free exhaust area.
- Failure to provide this venting will reduce the fan's airflow capacity. In addition, it will lead to noisy operation and ultimately failure of the fan motor.