Whole-house fans are designed to cool an entire house by pulling hot air out of the living space and pulling cooler air in through windows and doors. They are typically installed in the ceiling and can be an effective way to cool a home without using air conditioning. Attic fans, on the other hand, are designed to ventilate attics and reduce heat gain in the summer. They are usually installed in the attic space and work by pulling hot air out of the attic and reducing the temperature in the living space below.