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Is it TOO hot? How about a Whole House Fan?

SMP has been installing Whole House Fans for over 10 years. Whether your home is 1,000 square feet or 10,000 square feet, if you have an attic, a Whole House Fan is the way to go. The area of the country with the best climate to install a Whole House Fan is Orange County, California. Why? Warm dry days - Cool dry nights.

Let us explain:

It's a hot day in Orange County. The temperature outside during the day is 95 degrees. The temperature in your attic is 140 degrees. It's now 6:00pm and the outside temperature has dropped to 70 degrees but the temperature in your attic is still 138 degrees. In other words, you have a massive "heat load" in your attic. You turn on the A/C - your house cools - the A/C shuts off. You wait 45 minutes and you go through that same cycle again and again. The main reason is the heat load in the attic. If you stand on a chair and place your hand on the second floor ceiling - It's HOT! The hot air in the attic is trapped and there is no way to get it out. The heat load continues to warm the home when the A/C is turned off.


Firstly, its just a simple fan usually installed somewhere out of site in the ceiling of the second floor. When turned on, the fan draws air from the second floor. The fan then draws air from the living space of the home and pushes it into the attic. In order for this to happen successfully, windows on the first floor must be opened a small amount. The windows act as "dampers" and allow the outside ambient air to enter the home. That cool air (70 degrees) is drawn into the home and up to the attic. Venting in the attic allows the fresh air to escape, taking the hot air with it. Think of blowing air into a paper bag and the bag has a hole in it. It's the same principal. Whatever the temperature is outside - the temperature in the house drops to that level. The hot air in the attic has been displaced with outside ambient air and the temperature now drops to that same lower temperature too.

Our Southern California climate works best with a Whole House Fan system. As you can well understand, this process does not work during the day. It's designed for the evening hours only when the temperature outside is cool. It cools the bedroom areas and makes it much more pleasant for sleeping as well as bringing in fresh air from outside and displacing any stale air. Remember, the Whole House Fan displaces the air in your home with the air outside and will reduce the amount that you will use your Air Conditioning dramatically. The Whole House Fan uses the same amount of electricity as a typical light bulb.

Santa Margarita Plumbing, Heating & Air is pleased to serve the communities of Rancho Santa Margarita, Mission Viejo, Ladera Ranch, Coto de Caza, Dove Canyon, Robinson Ranch, Foothill Ranch and Rancho Cielo.

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