Whole-house fans operate in a fairly simple manner. The system pulls hot air out of a house and vents it through the attic. Cooler air moves in through the windows to replace the hot air, and the house cools. The fans were the main source of cooling in the first half of the 20^th century, before residential air conditioning became common. In the right conditions, they still provide a good option to homeowners who want to avoid running their air conditioning all the time. But homeowner interest remains limited, and many HVAC contractors avoid the market.

The main reasons for limited homeowner interest in whole-house fans is they require one key element — cooler outside air. Paul Scelsi, marketing communications manager at Air Vent Inc., said his company’s fans work best in climates like the Northeast. In Dallas, where he lives, the outside air rarely meets the right conditions during the summer.

David Peavey, owner of PV Heating & Air in Atlanta, said his only experience with whole-house fans is removing them from older homes. The hot, humid climate in Georgia makes them impractical. What’s more, the needed ventilation creates leakage that works against the air conditioning.

“You could probably only run that fan one week a year,” Peavey said.

Cool Nights, High Bills Create Environment for Whole-House Fans

Neil Smith, owner of Air Scape Fans, said the best markets for whole-house fans combine the right physical climate with the right economic climate. California is a perfect example. Most of the state has low temperatures at night due to it being a mostly desert climate. Southern Oregon has a similar climate, but much lower utility rates. As a result, California is the stronger market.

“What motivates people to get a whole-house fan is the cost of electricity,” Smith said. “What gets people to keep a whole-house fan is better comfort and better indoor air quality.”

The market for whole-house fans is growing, in part because of improved performance. Older whole-house fans were noisy, Smith said. As a result, people would run the fan for a short time and fail to get the full effect. Running the fan all night does more than create a comfortable sleeping environment for the occupants. It cools the entire structure, so it takes less energy to cool the house during the day.

Whole-house fan installation is fairly simple and is performed by a range of trades in addition to HVAC contractors, including electricians, handymen, and even some roofers. Smith said some HVAC contractors view whole-house fans as competition. He said they should view it as an added value for customers.

“We’re helping you help your customers,” Smith said.

Kevin Kalka, president of Kalka Plumbing Heating and Air in Irvine, California, sees it that way. Kalka started installing whole-house fans several years ago. He said consumers often contact him seeking solutions to warmer rooms in a house’s upstairs that don’t require a full overhaul of their HVAC systems. They also want to avoid running their air conditioning all the time. Kalka said that’s when he suggests a whole-house fan. In addition to the installation, Kalka said he gains service work,

Scelasi said HVAC contractors who do offer whole-house fans need to make sure they understand the requirements to make the systems operate optimally. HVAC contractors need to make sure the attic has adequate venting.

“Don’t just take the money for the whole-house fan and leave,” Scelasi said.

Kalka said sizing proves one of the biggest issues for whole-house fans, such as it does for air conditioners. He said installing too large a unit in a house with an unsealed attic can create negative pressure and defeat the purpose of the fan.

Smith said the market for whole-house fans is growing and the systems are improving. Airscape features motorized doors that keep out pest and unwanted air. A key new feature, Smith said, is intelligent scheduling, which allows the homeowner to set the fan to run at different speeds through the night.