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Summer days in Grass Valley, Nevada City, Penn Valley and surrounding areas can get really hot. Hot days spent at our beautiful rivers and lakes makes Nevada County a fun place to be during the summer months. However, escaping the heat at home can be challenging while watching your monthly utility bill (if you are lucky enough to have air conditioning). Most of us have spent a restless night too hot to sleep. Ceiling and oscillating fans only move the hot air around the room. A whole house fan will replace that hot air with cooler air from the outside. Whole house fans are very effective at cooling a home anytime outdoor air temperature is cooler than inside your home. A whole house fan is an excellent way to decrease the amount of time the air conditioner needs to be run. Thus helping to keep your electric bill under control.

Designed to pull out hot air from a house or building, a whole house fan serves the purpose of an exhaust system. Many people confuse a whole house fan with an attic fan, but the two accomplish different goals. Because whole house fans were cheaper than air conditioners and worked well, they began being used in the 1950s, primarily in the South.

For homes or buildings with a whole house fan, the hot air is pulled into the attic. Due to positive pressure, air in the attic is pushed out through the vents or gables. Simultaneously, negative pressure is created in the living area, which helps to draw cooler air in through the windows. On the other hand, attic fans simply force hot air out of the attic. Attic fans don't provide a cooling relief to the living area. Although whole house fans may be installed in an attic, they have a much more comprehensive goal of cooling the entire home or building.

A whole house fan is economical and practical. It can substantially lower the temperature in a home or building rapidly. It's certainly much more affordable than air conditioning. Newer models of whole house fans are not only energy efficient, but environmentally friendly as well. Whole house fans can rapidly reduce interior temperatures within a matter of minutes. Windows must be open for the whole house fan to work most effectively. These types of fans are best used in the morning or evening when the air outside is cooler and fresher. This will allow the cooler air to be drawn into the home when the whole house fan is turned on.

In climates that are mild and temperate, a whole house fan can completely eliminate the need to have air conditioning. The operating cost of a whole house fan is much cheaper than running air conditioners. Home improvement experts agree that a whole house fan can be run at one-tenth the operating cost of air conditioning, you may be able to reduce your energy costs by 80 percent by installing an energy efficient whole house fan. Standard home size whole house fans are typically having a diameter of 24 to 36 inches, but the fan size may need to be adjusted to conform to the living space size. Theos Electric will determine which house fan size is appropriate for your home or building.

How many windows do I need to leave open? Which ones? How far?

Opening two or more windows halfway or wider is recommended to allow the fan to do its job. For general cooling, open windows far away from the fan to provide airflow to the whole house. Or, open windows strategically in the areas you want cooled. For example, if you want bedrooms to be the coolest then open windows in those bedrooms. Each house is different so we advise our customers to experiment and see what works best for you and your home.

Important Tips for Operating

Only use it when the outdoor air is cooler than your indoor air. Except if you want to bring warm air into your house. Wait, what? The main reason to install a whole house fan is to cool your house during the hot summer months. However, you can also operate it during the fall and spring months. If your house is cooler inside on a warm sunny day, turn on the fan to pull that fresh, warm air inside your house.

Make sure your A/C is off when you run the fan to avoid expensive energy bills.

We recommend running the whole house fan all night. The goal is to cool your entire house down, not just the air. It takes time to pull the heat out of the sheetrock, structure and contents of a structure. By ventilating throughout the night, the house starts the next day cooled to the core, which delays or eliminates the need for A/C. Use high speed to 'kick-start' the cooling, and use low to run quietly through the night. However, timers are available if you prefer to run it for a few hours and have it turn off automatically. Just be sure to let Theos Electric know you want this added feature during your free consultation.

Never operate the unit without opening a window first. This can create negative pressure in the house and cause dangerous back drafting with gas appliances.

Unfortunately, not every house is built in a manner that allows for installation of a whole house fan. Theos Electric will be able to tell you if a whole house fan will work in your house. So don’t buy one and then call an electrician to have it installed! If you want to do the shopping yourself, make an appointment for Theos Electric to inspect your house and make a recommendation on which model will work for your house. Then schedule a time when it arrives to have us install it for you.

Purchasing and installing a whole house fan is a large financial decision. Theos Electric wants you to be happy with making that decision and have no regrets. That is why we are going share one possible, rare drawback of operating a whole house fan. For people with extreme pollen allergies that live in an area with vegetation that produces large amounts of airborne pollen, using a whole house fan may increase those allergy symptoms. While pulling in fresh, cool air the fan will also draw in pollen. We have only had one complaint of this being an issue. It was a family with a child that had asthma attacks that could be triggered from his allergies. They still use the fan just not during the time of year when pollen is at high levels.

One last tip. If you are like me, you or someone else has burned food in your kitchen causing your house to fill with smoke and setting the smoke detector off. In my old house I would open and shut the front door trying to bring in fresh air or frantically wave a towel under the smoke detector to get it to go off. Now that I have a whole house fan, I open a couple of windows in or near the kitchen and turning on the whole house fan, the smoke will quickly be drawn out of your house. I have even used it during cold winter months as it doesn’t take long to get the smoke out. We have also used it to draw odorous food smells (cooked fish) out of the house.

If possible Theos Electric wants to help you save money on purchasing a whole house fan. Ask us about available rebate information or look for yourself on PG&E website.

Please note NOT all brands and models are eligible for rebates. Also, some of these rebate programs run out of funding or expire. Theos Electric will do our best to help with receiving a rebate but please do not count on it.

Contact Theos Electric today at (530)265-6362 or by email at to schedule a free consultation to find out if a whole house fan is right for your house. The sooner the better so you can start saving on your electric bill!