Designed to create better ventilation, cooling and air circulation, these units can be both energy-efficient and extremely effective. Although they come in many different forms, whole-house fans often have filters that help keep outdoor air pollutants from becoming an indoor air quality problem.
With the right filters, your whole-house fan can give you better interior air quality without bringing outdoor pollutants. Let’s take a closer look at air filters for whole house fans so you can make the right choice for your home.
Understanding Whole House Fan FiltersIf air is simply being circulated throughout a home, why would you need a filtering system? For example, if you are using a fan to create air movement from the living space into the attic, it wouldn’t make sense to filter the air that travels upward.
However, it can be useful to filter air that travels into the home. Some types of whole-house fans bring air from the outside and at the same time push air out of your house. In these cases, it makes sense to have a filter, as the outdoor air could contain contaminants, especially dust or, if you live in a metropolitan area, exhaust fumes.
There are generally two types of whole-house-ventilation systems that need filters: heat-recovery ventilators (HRV) and energy-recovery ventilators (ERV). These are systems that use one or more fans and a heat exchanger to create home ventilation. Because these two systems pull air inward, they need a filtering process to ensure they are providing clean, reliable air.
These ventilation systems use the heat exchanger to transfer a certain amount of water vapor to create warmth in the air. It transfers some of the moisture from the exhausted air to the incoming air, which is usually less humid. This helps the humidity of the house stay consistent and keeps the heat exchanger core warm. In the summer, using an energy-recovery system can help control humidity in the home.
Energy-recovery systems can help recover about 70% to 80% of the energy that is contained in exiting air and deliver that energy back to the incoming air. They are most effective in areas with high utility costs, especially locations with either extremely cold winters or extremely hot summers.
Why Are Filters for Whole House Fans Important?These systems require outdoor air to be pulled inside, which means contaminants from the outdoors can easily be brought into your indoor space. To be fair, most outdoor air is completely healthy, and there’s strong evidence to support the theory that indoor air is more contaminated than most outdoor air.
However, it never hurts to filter the air coming from the outside. The EPA lists numerous airborne pollutants that can cause health problems and aggravate respiratory conditions.
The EPA lists six “Criteria Air Pollutants,” which are all a special concern to health officials. Particulate matter is one of the most common types of pollutants in outdoor air. This is essentially a mixture of solid particles that are small enough to float in the air. It can include dust, dirt, soot, and smoke. Areas with heavy traffic are often plagued by particulate matter, and locations with wildfires (or locations downwind of wildfires) often deal with this type of air pollution.
Ground-level ozone can be troubling for outdoor air quality as well. This is the harmful type of ozone that sits closer to the ground and is created by the chemical reactions between nitrogen and volatile organic compounds. Pollutants emitted by cars and industry can cause ground-level ozone, which is linked to chest pain, coughing, throat irritation, and more.
Carbon monoxide, sulfur dioxide, nitrogen dioxide, and airborne lead particles are all concerns of the EPA as well.
While we have made great strides as a nation to limit these outdoor air pollutants, they are still present. If you use a whole-house fan that brings air from the outdoors into your home, you need to make sure a filter is present so you aren’t bringing polluted air into your living space.
The Different Types of Filters for Whole House Fans
HEPA filtersSome whole-house fans use HEPA filters to purify the air coming into the home. HEPA filters are high-efficiency products that are designed to trap even the most microscopic of air particles. They use a fine mesh that captures the particles as they pass through the pleated air filter, and can be used to trap pollen, particulate matter, and other outdoor air pollutants that might try to enter your home. HEPA air filters tend to have a high air flow resistance so be sure to check it is not too restrictive for your fan.
Pollen ScreenPollen screens can also be used to keep pollutants from entering your home. If you use a whole-house fan that creates ventilation through the windows, having a pollen screen will reduce the amount of contaminants in your home. They can replace ordinary screens to filter out roughly 90% of common pollens. If you suffer from hay fever but want to install a whole-house fan, using pollen screens may be a wise decision.
Window Screen RollsThis is another type of material that can be used to filter outdoor air pollutants. Window screens can reduce the amount of pollen, dust, dirt, and soot that comes into your home, creating a healthier space for you and your family. These products are available in many sizes to fit a wide range of windows.
Electronic FiltersSometimes called electrostatic precipitators, these high-tech filters can be incorporated into a home’s ductwork to provide advanced filtration. It uses an electrostatic charge (i.e static cling) to trap and hold solid particles. This type of filtering can work on smoke and particulate matter, and it can trap some of the small particles that other filters may miss. However, this type of filter creates ozone, making it harmful for use in the home. Its most common application is for cleaning the air that exits industrial smokestacks.
UV Light FiltersUV light filters are especially useful for destroying organic matter that may be contaminating the air, such as mold spores. Germs and bacteria can also be reduced by UV light, although there is still limited information on the effectiveness of UV light on these organisms. These types of filters pull air through a UV light chamber, effectively removing many of the living air pollutants before they are released into the atmosphere.
How are Whole-House Fan Filters Installed?Depending on the type of system you have, there are a lot of ways that filters for whole-house fans can be installed. If you are simply using a screen or mesh in place of traditional window screens, they should be fitted properly to ensure that no cracks or gaps exist between the window frame and the screen. These types of products can be installed fairly easily, but if you want to ensure they are installed properly, you may want to hire a professional who is properly trained and experienced.
Other air filters may need to be installed into the fan system or the vents of your HVAC system. Again, this will depend largely on the specific type you have for your home, so check with any sales staff or installation professionals to see what filters you need and how they will be installed.
The Importance of Whole-House Fan Filters for BusinessesClean indoor air is important for the home, but it’s just as important for businesses, no matter the industry or specific type of work. While air quality at work is often associated with construction or industrial jobs, office locations will also benefit from having clean, purified air.
If you use a whole house fan or indoor ventilation system at your office building or work facility, you should be aware of the importance of high-quality air. The EPA has provided a wealth of information on air quality. They recommend having a ventilation system that is designed to provide clean air to all occupied areas. They also say that an adequate supply of outdoor air should be brought in, which will typically be brought through the facility’s HVAC system. This outdoor air is important for diluting indoor pollutants, and distribution should ensure the clean air goes to the appropriate spaces.
When you bring in outdoor air to a work facility, carbon monoxide, pollen, dust, and other outdoor pollutants may come along for the ride. This means you need to have properly-installed filters that are maintained on a consistent basis. These filters should be able to trap the contaminants before they enter the occupied space of the building. If you need to control gas or chemical pollutants for any reasons, advanced filtration methods may be required.
Get Advanced Air Purifiers for Even Better Air QualityYou and your family deserve high-quality air purification. Contact Oransi and we’ll help you choose the right house air purifiers and filtering products to reduce indoor air pollutants, including dust, allergens, and harmful chemicals. Oransi's air purifiers utilize real HEPA filtration to clean your indoor air.
With a full selection of industry-leading air purifiers, we have the right items to ensure long-lasting home health.