How Do Whole House Fans Work?

The warm weather found in Southern California can be particularly draining on the wallet. The high temperatures that can happen at any time of the year means that air conditioning can be a year round endeavour. Comfort sometimes requires lots of energy consumption, which in turn means a hefty bill to pay the following month. Americans spend 22 billion dollars each year on energy alone. For this reason and many more, people are dropping their air conditioners for the once popular whole house fan.

By using 90% less energy than the conventional AC, a whole house fan offers the added benefit of cooling your home without breaking the bank.

Also, whole house fans can operate in quite a number of warm climates, the only prerequisite to their ability to function being that the air outdoors remains warmer than the air indoors.

This article focuses on the few things you need to know about whole house fan installation and usage.   

How Does it Work?

Most often installed in attics, a whole house fan pulls cool outdoor air in and then exhausts the warm indoor air out through the soffit or gable vents. The fan won’t work properly if warm air doesn’t have a clear exist out of the house. Hence, all windows must be open to encourage proper ventilation, guaranteeing the home with 30 to 60 air changes per hour. This exhaust system essentially provides the house with adequate cooling and ventilation by consuming only a tenth of the energy that air conditioners use.

Fan Use Strategies

There are several ways to really reap the benefits of your whole house fan. For homes already utilizing an AC unit, you can simply use your fan at night. Since the fan works best when outdoor air is cooler than indoor, nighttime usage guarantees the proper coolness and ventilation you’re seeking.

Also, the pre-cool method is equally useful. This requires that the unit remains turned on throughout the night. Then, rather than turning on your AC the following day, trap in the cool air by sealing all openings in your home. This essentially reduces your reliance on, and can possibly eliminate the use of an AC. As a result, your household significantly consumes less energy.

In general, whole house fans are much more effective when used in the mornings, evenings, and/or nights — during the coolest times of the day. When used during these peaks hours, they bring down the indoor temperature significantly, providing you with a cheap alternative to cooling your home.

Depending on the climate you’re in, you may even operate your fan as the sole cooling unit in your home for much of the year.

A Few Things to Keep in Mind

Making the decision to invest in a whole house fan is an important step in the right direction. Southern California is uniquely positioned well to use them: fan works best under dry conditions when the evening and night temperatures are much cooler than the daytime highs. Keep in mind that while the attic is the best place to install a fan, crawlspaces and garages work as great substitutes.