January 9, 2024
Understanding the Different Types of Furnace Filters

Furnace filters help protect your HVAC appliance from particles, debris, and grime that could otherwise damage the unit. Without a proper filter, grime can accumulate on the furnace’s internal components. This accumulation causes the unit to work harder to heat your home and draw more energy in the process, resulting in a spike of heating bills. The overwork and buildup can also lead to deterioration that requires repair or replacement of the unit.

In addition to preventing your unit from clogging, furnace filters are also very important for trapping contaminants that could otherwise blow out of your furnace and circulate throughout your home. For this reason, the effectiveness of your filter is essential for maintaining high indoor air quality (IAQ). A look at the major types of furnace filters can help you make an informed decision for your home.

HEPA Filters

HEPA is a label that stands for “high-efficiency particulate air” filter. A filter with the HEPA designation must meet certain requirements for removing very small particles from the air. According to the Environmental Protection Agency (EPA), HEPA filters can capture 99.97% effective in airborne contaminants that are as small as 0.3 microns (µm). Experts recommend HEPA filters for individuals who suffer from allergies or asthma. Households with pets, children, and elderly occupants can also benefit from HEPA filters. Depending on the model, some HEPA filters integrate directly into the central air system and can include ultraviolet light to kill bacteria, viruses, or other pathogens. An HVAC professional can help you choose the correctly sized HEPA filter to prevent restriction of airflow or incompatibility with your furnace model.

Fiberglass Filters

Fiberglass filters offer a sturdy and dependable option for average-sized households. According to the Department of Energy (DOE), fiberglass is one of the most popular materials for home insulation. But the fibrous nature of this synthetic material also makes it effective for removing large airborne particles. Fiberglass can trap 80% of particles as small as 50µm and 25% of particles that range from 3.0-10µm. These furnace filters can help prevent debris from accumulating on the heat exchanger, blower, or motor while enabling maximum airflow. However, fiberglass filters are not as popular for filtering contaminants smaller than 3.0µm in size.

Polyester Filters

Polyester furnace filters are famous for their durable construction and medium sizing. They often provide an economical choice for homeowners who need an effective solution for household allergens. Polyester filters can remove 80%-95% of large particles for improved indoor air quality.

Electrostatic Filters

Electrostatic furnace filters use an electric charge to attract and trap airborne contaminants. Many electrostatic models use ionizing technology to capture dust, pollen, pet dander, and other small particles. Some models are also washable and reusable, making them eco-friendly alternatives to traditional filters. However, it is important to work with an HVAC professional for routine maintenance to prevent problems with a washable filter. Overusing a dirty or improperly installed filter can lead to the growth of mold and mildew. These contaminants can create mechanical problems and compromise the quality of indoor air.

Carbon Filters

These filters use activated carbon or charcoal to trap pollutants. Experts recommend uses carbon filters because they may also help remove unwanted gases from the air. Most carbon filters use a process called adsorption. This is a transfer process in which unwanted molecules attach or adhere to the surface area of the filter’s carbon molecules. Following the adhesion of unwanted particles, the cleaner air can then reenter the HVAC appliance or room.

Factors To Consider When Choosing a Furnace Filter

Different type of filters also have features that may impact your home. These factors include size, thickness, pleating, and efficiency rating.

Filter Size

Common sizes for furnace filters include 16″x20″, 20″x25″, or 1mainten6″x25″. An HVAC professional can help you choose the right size for your heating system. Filters that are too small can restrict airflow, but filters that are too large can enable the passage of dust and debris that damage your system hardware.

Filter Thickness

Filters range in thickness from 1.0″-5.0″. Your heating system’s configuration can help determine which measurement is compatible for your home. An HVAC professional can help select a filter that is thick enough to capture a large volume of particles and last longer without restricting airflow.

Filter Pleating

Pleating can increase a filter’s available surface area, thereby enabling it to trap a greater volume of contaminants. If you want a pleated versus non-pleated filter, reach out to an HVAC technician to find a model compatible with your furnace unit.

Filter Efficiency Rating

Another factor to consider is the minimum efficiency reporting value (MERV) rating. This rating describes how effectively a filter can remove unwanted particles. According to the EPA, MERV ratings rank on a scale from 1-6. In general, the higher the MERV rating, the more particles the filter can remove to keep your unit clean.

Contact Us Today

The right furnace filter can promote a healthy indoor environment and help preserve the lifespan of your heating system. Apollo Heating & Air Conditioning provides furnace filters for homes in Bellevue, NE and surrounding areas. We offer heating maintenance, heating replacement, and more! Our technicians also provide furnace and heat pump expertise. In addition, we offer indoor air quality testing and duct cleaning. Contact Apollo Heating & Air Conditioning today for all HVAC needs.

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