Frequently Asked Questions

The QUIET COOL QC-1500 is the right choice for any home. If the saving of a few dollars on the original purchase price is the only important factor and you are willing to live with the loud noise, difficult and expensive installation, unsightly ceiling grill and the lack of thermal protection, then the Type 1 whole house fan might be better.

The only reason to buy the Type II whole house fan is if you live in a very cold climate and are concerned about maximum insulation values in the wintertime.

A WHOLE HOUSE FAN is a large fan mounted in a venturi housing and is installed in the attic. They are used to both cool and ventilate a house.

A whole house fan is able to cool your house in 3 ways:

1. They draw cooler outside air in through your open windows which lowers the room temperature by as much as 10 to 20 degrees F. Your open windows serve as intake “vents” which allow you to control the air flow by selecting how many or which windows you open.
2. The moving air blowing through the house cools the occupants. The cooling breeze can lower the skin temperature by 5 to 10 degrees F.
3. The cooler air, after passing through the living space, is forced into the attic which pushes the hot attic air out through the attic vents. This can lower the attic air temperature by as much as 40 degrees F. The attic can reach temperatures in excess of 150 degrees F. in summer, and that air, if allowed to remain undisturbed, will radiate heat down through the insulation to heat the living space. That is the main reason that a home, without the use of a whole house fan, remains uncomfortably warm in summer evenings, and that the upper floor of a multi-floor house is always warmer.

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 fan’s 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 3,000 to 4,500 CFM.

Overall attic venting is the only limiting factor on how many CFM can be efficiently moved. However, attic venting can be easily increased. Too many CFM for the attic venting can cause undue stress on the whole house fan and pressurizes the attic and walls. Too little CFM will not provide the desired minimum of 10 air exchanges per hour as recommended by the House Ventilation Institute, and may not provide the cooling draft to lower house, attic, and skin temperatures in a timely fashion.

See our Ventilation page explaining why proper ventilation is so important.

Effective ventilation is a process that keeps the air circulating and exchanges the over-heated and moisture-laden air in your house with cooler air from outside. Most homes built today are sealed tight during the construction process and allow almost no air infiltration. This is efficient for heating and air-conditioning a home (heating and air-conditioning systems recirculate the same old, inside air over and over again) but makes it all the more necessary to ventilate. Without ventilation, moisture, cooking odors, tobacco smoke, and other foul-smelling odors are locked into the house and cannot escape.

Moisture in the air comes from everyday activities such as cooking, bathing, laundering, and even breathing. Moisture that is allowed to remain in a closed house can create many problems for the homeowner. The most serious is mold growth, which can seriously threaten the health of all the people in the house. Mildew is another problem, which is usually encountered around showers and laundry facilities. The moisture in these areas generally causes problems with peeling paint and wallpaper, but under the surface, structural damage may be taking place. Moisture can also be present in the attic and this dampness can deteriorate the insulation and also cause structural damage.

Did You Know?:

• Doctors are now recognizing that “sick” homes can damage people’s health and vitality, decrease their productivity, increase their health costs, and reduce home values.
• Today’s homes contain over 1,500 hazardous compounds from approximately 3,000 man-made products. Even low levels of pollutants emitted by these products will affect human health over a period of months or even years.
• The EPA recently rated indoor air pollution as one of the five most urgent environmental issues, accounting for over $1 billion annually in direct health care costs and up to $60 billion annually in lost productivity.
• A 1999 Mayo Clinic study associated nearly all of the chronic sinus infections afflicting 37 million Americans with molds. Recent studies also have linked toxic molds to the tripling of the asthma rate over the past 20 years.
• The EPA has stated that 50%of all illnesses are caused or aggravated by indoor air pollution.

A whole house fan is by far the best method of providing ventilation for the whole house.

Every time a whole house fan is operated, it draws the foul air within the house up into the attic and then forces it out of the attic through the attic vents.

There are basically three different types of whole house fans on the market today.

TYPE I

The first, Type I, is the most common. It is a 20” to 36” diameter fan, either a direct drive or belt driven assembly that mounts to the ceiling on the attic side. It requires a large cutout in the ceiling and uses a moveable louver grill to cover the hole in the ceiling. They move a large volume of air (3,000 to 9,000 cfm) and do an excellent job of cooling and ventilating a house Their main advantage is that they are the least expensive to purchase; but they have many disadvantages such as:

1. They can be difficult and expensive to install.
2. They are very noisy in operation.
3. It can be difficult or impossible to find an ideal location for them in many homes.
4. They do not cool or ventilate an individual room when the room door is closed.
5. They offer little thermal insulation protection in cold climates in winter.
6. Belt drive models require periodic maintenance.
7. They appear unattractive in the ceiling.

TYPE II

The second , Type II, is a small volume (1,000 to 1,600 cfm) fan assembly with motor driven shutter doors that mounts directly to the ceiling. They use less power to run, and their main advantage is their exceptional insulation qualities which are useful in extremely cold climates in wintertime. It does have several disadvantages:

1. They are the most expensive to purchase.
2. Their noise level, less than most Type I whole house fans, is still a bothersome whine and is unacceptable to most people while viewing television or sleeping.
3. They provide very little cooling or ventilation in a timely manner when installed as recommended by the manufacturer.
4. They are inexpensive per hour to operate, but require many hours of run time to accomplish their purpose.
5. They do require some carpentry framing modification to install.

TYPE III

The third, Type III, is a QUIETCOOL QC-1500. (U.S. Patent # 7497774) It is an innovative whole house fan that has none of the disadvantages of Type I and Type II.

It’s big advantage is that it is not mounted to the ceiling but instead is suspended in the attic with straps from the roof rafters. It’s connected to an attractive ceiling grill with a flexible accoustical insulated duct, thus eliminating all vibration, rattle and noise in the house. It is so quiet in operation that it can be installed in a bedroom or sleeping room without a sleeping person being able to hear it.

This cleverly engineered system can be installed almost anywhere in a ceiling or vertical wall in less than 1/3 the time it takes to install a Type I or Type II whole house fan. It has a damper with insulated doors that prevents cold air intrusion in the wintertime. One QC-1500 performs better than one Type II whole house fan in all respects, but we recommend that one QC-1500 be installed for each 500 Sq. ft. of living space (ideally one per bedroom) to obtain the cooling breeze of a type I whole house fan. This also allows the cooling and ventilation to take affect even with the bedroom door closed as long as a window is open.

A whole house fan is by far the best method of providing ventilation for the whole house.

Every time a whole house fan is operated, it draws the foul air within the house up into the attic and then forces it out of the attic through the attic vents.