A whole house fan is a ventilation cooling system that uses less energy than a traditional air conditioner. This energy-efficient system works by pulling cool, outdoor air into your home and out your attic vents. This helps keep the mass in your home cooler than an air conditioner can. These whisper-quiet and energy-efficient wonders are the #1 residential cooling & ventilation appliance on the market. With a whole house fan, you’re able to turn off your most expensive appliance, air conditioning, while improving the air quality and comfort of your home for just pennies per hour.