Spun fiberglass is an affordable and reliable resource for filtering air and trapping pollutants. It is great for trapping large contaminants, such as dust and pet dander, and often helps maintain superior airflow. Many HEPA filters are mainly composed of fiberglass. To measure filter efficiency, experts use the Minimum Efficiency Reporting Value (MERV).
This graph classifies filters based on their ability to capture particles, with a rating ranging from 1 to 16. The highest rating is given to the air filters with the best filtering capacity, which is always mentioned on the package. Despite their popularity, these filters don't contribute much to indoor air quality. They can only filter about 20% of particles between 3.0 and 10.0 microns in size. These substances include dust, carpet fibers, and pollen, which “inhale” through the ventilation grilles of the home, drawing air through the ducts and through the heating or cooling source (whether the burners of an oven or the coil of an air conditioner or a heat pump). The pleated material of these filters can cover 75 square feet when unfolded, even though they are no larger than six inches.
The primary function of HVAC air filters is to remove harmful particles from the air as it flows through the system. Since it is not as dense, in theory it should be less restrictive, allowing more air to enter and increasing power. At the lower end of the scale, these filters are made of fiberglass or mesh and can capture large particles such as hair, fibers from clothing and carpets, and some pollen. Because of their high efficiency, these filters are popular among people who have an allergy to air conditioning or other respiratory problems. An air filter is a simple device that's vital to the proper functioning of your car, but there's more than one type on the market.
If you're ready to find the right air filter for your boiler or air conditioning unit, you can search by filter size or by MERV rating. The shape of the unit can affect its performance, as can its size: the smaller the area through which you are trying to introduce air, the more restrictive the configuration will be. Therefore, to choose the type of HVAC filter that is most suitable for your home, you must understand how well each type of filter material works. This high-quality, plastic-based synthetic material allows filters to trap particles as small as lint, dust mites, mold spores, pollen, pet dander, fine dust, smoke, viruses and bacteria. Typically, both sources offer the right sized air filter for the system while aftermarket manufacturers such as FilterBuy add additional features such as odor blocking, a higher MERV rating and easier-to-replace designs. For these reasons and since all forced air heating and cooling systems use at least one filter it's important to know how and when to replace it.
However, some air conditioning systems have filters inside the return air ducts scattered throughout several rooms in the house.
