How Whole House Fans Work
Anytime it is cooler outside than the inside of a home, the QuietCool whole house fan (as known as an attic fan) will work effectively & quietly. In the summer, this normally happens in the late afternoon to early evening and through to the next morning.
When the QuietCool whole house fan is turned on, the fan will pull the cooler outdoor air into your home, through your windows, across your living space, into the attic, and out the attic vents replacing the hot stale air. This helps cool the home and attic by up to 30 degrees, allowing it to stay much cooler the following day.
The cool breeze begins when a window or two is opened and the QuietCool fan is turned on. The cooler outside air will immediately begin to create a breeze inside the home making the homeowner feel up to 10 degrees cooler, instantly.
This breeze will be carried through your home to each QuietCool whole house fan that is on and in use; thus beginning the cooling process. At the same time, the cooler outdoor air will be brought into the attic and pushed through the attic vents causing the hot stale air in the attic to be exhausted. Exhausting the hot air inside your attic will allow your home to stay cooler throughout the day.
Whole house fans are rated according to the amount of air they can move. This is measured in cubic feet of air per minute, or CFM. In order to be effective, a whole house fans CFM rating should be 2 to 3 times the square footage of the house.
For example, a 1,500 square foot house should have a whole house fan system capable of moving 3,000 to 6,000 CFM of airflow.
Overall attic venting is the only limiting factor on how many CFM can be efficiently moved. Attic venting can be easily increased by adding vents. Too many CFMs of airflow without the proper attic venting can cause undue stress on the whole house fan and pressurizes the attic and walls. Too little CFM’s will not provide the desired minimum of air exchanges per hour as recommended by national ventilation experts and may not provide the cooling draft to lower house, attic, and skin temperatures in a timely fashion.
Whole House Fan comparison – A Quick Review
There are many reasons why QuietCool fans are the best choice compared to traditional whole house fans
- Quietest Whole House Fan On The Planet
- Low Energy Usage (70-650 Watts)
- Models With “Energy Saving” Motors
- Innovative & Highly Insulated Damper System
- 10 Year Manufacturer Warranty
- Maintenance Free System
- No Custom Framing or Joist Cutting
- Single or Multiple Fan System
- California Title 24 Compliant
- Built In The USA!
Traditional Whole House Fans
- Extremely Inefficient, 300-500 Watts
- Older Design and Inefficient Motors
- Unsealed Hole In Ceiling
- Short Warranty Period
- Periodic Worn Belt Replacement
- May Require Custom Framing, Joist Cutting
- Too Loud For Sleeping, Watching TV, Etc.
- Normally Made Overseas
- Much Higher Noise Levels
- Overstated Airflow/CFM; Measure Without Louvers Installed
To understand how QuietCool works, we first have to revisit how air conditioning works.
Take a typical American home during a hot summer…
The homeowner comes home after a hot day at work… the outside temperature has reached 90… maybe 100+ degrees … the attic is 140 … inside, it’s 90… and the homeowner turns the air conditioner on… now, let’s switch between “tech talk” and “reality talk” …
Tech talk — an air conditioner cycles the hot “ambient air” within a home through a closed loop system (ducting) that removes the “heat” within the ambient air which then returns as cooled air into the living space.
This cycling of hot-to-cooled air continues until the wall thermostat “senses” that the ambient air temperature has dropped to the “set point” — the temperature that the homeowner “sets” the A/C to go on and off — and the A/C unit turns itself off.
Reality talk — what happens next? Usually within 10 minutes or so, the A/C unit cycles back on… and this cycling on and off continues … well, it continues sometimes all night long, especially in the hotter climate zones throughout the country. The question is, “why?”
More tech talk — The key words above are “ambient air.” An A/C unit merely removes heat from ambient air, but it doesn’t cool down “the house itself.”
The “house itself” is the key to why QuietCool works!
The “house itself” is called “mass.” “Mass” comprises all that is within the house that can retain “heat.” We call this “thermal mass.” The basic principle of “thermal mass dynamics” states that all mass retains heat. The mass within a home includes the floors, wall, furniture, ceilings, curtains and carpets, and the more mass there is — and the more heat the mass is exposed to — the longer it takes the home to cool down!
As you can see illustrated in the graphic to the right, the QuietCool system brings cool air into the home through selected open windows, and the hot air is pushed out of the attic vents giving you a complete air exchange every 3-4 minutes.