Fiberglass air filters are composed of spun glass enclosed in a cardboard frame. They are an inexpensive option due to the affordability of the materials used to make them. While they are generally safe, they are not as effective as pleated filters when it comes to filtering out the smallest contaminants, such as pollen, pet dander, and bacteria. Over time, they can cause buildup and weaken your HVAC system, leading to higher energy costs.
Fiberglass filters are made of 15 to 60 μm glass fibers with a high porosity. They are used in residential heating and air conditioning systems to protect the system from debris that could damage components. Manufacturers recommend changing these filters once a month during normal use seasons. Oven filters can also be made of cotton, polyester, and other synthetic fibers, as well as carbon filters that use charcoal to improve air quality.
Fiberglass filters provide near maximum airflow but filter out only the largest particles, earning them the nickname “rock catchers” in the industry. They are referred to as “disposable” or “disposable” filters because they need to be discarded and replaced after about 30 days. Cotton filters have higher ratings and their fibers can self-charge to remove the smallest particles from the air. Fiberglass air filters have a MERV rating of 1 to 4 and can generally remove larger particles from the air, such as pet hairs, dust rabbits, and animators.
They are economical compared to more advanced filters like pleated filters or whole-house air filters. However, pleated air filters have no impact on performance in most modern HVAC systems and provide better filtration efficiency with no increase in airflow resistance. Panel filters can also be used in HVAC systems to keep the oven working properly and protect it from dirt by removing unwanted particles from the air. They are the most effective at cleaning the air in your home but not practical for most HVAC systems since they are very thick.
It is important to regularly change air filters to keep the system running at peak efficiency and prevent harmful particles from infiltrating the oven and lungs. Fiberglass air filters may be economical but pleated air filters provide better filtration efficiency with no impact on performance in modern HVAC systems.