Call 801-207-7976 Now for an Appointment

Furnace air filters have two functions – to improve indoor air quality and to extend the lifespan of the HVAC system components. Filters achieve these objectives by removing contaminants before they reach the furnace.

Effective filtration is critical for clean air and optimal HVAC system performance. Homeowners need to replace furnace filters every so often, and they come in a range of types and sizes. The minimum efficiency reporting value, or MERV, can also vary. The following guide explains everything you need to know about home furnace air filters.

Furnace air filters 101

When to Change Your Furnace Filter

Furnace filters get clogged with contaminants over time, so they require replacement on a regular basis. Generally, a change is necessary at least every three months, but large households and families with pets may need to replace air filters more frequently.

Types of Furnace Filters

Several types are available, each of which has distinct advantages. Homeowners can select from the following furnace filter classifications:

  • Fiberglass or synthetic, which is inexpensive and disposable
  • Polyester, which offers better protection against contaminants
  • Electrostatic, which comes in washable versions that are longer-lasting
  • Pleated, which provides improved results without compromising airflow
  • High-efficiency particulate air (HEPA), which effectively traps contaminants to create a healthy home environment

Furnace Filter Size

When it comes to air filters for HVAC systems, one size does not fit all. The length, width and depth vary, and the proper size is essential to prevent airflow obstruction and effectively eliminate contaminants from the environment.

Before shopping for a replacement, homeowners should slide out the old furnace filter and check its dimensions. If the size isn’t printed on the frame, a search of the model number will reveal the correct dimensions.

Furnace Filter Ratings

Every furnace air filter has a MERV rating, a score that indicates how effectively it provides air filtration. The higher the number, the better the filter works.

MERV 1 – 4

Primarily designed to keep the HVAC system clean, but also removes pollen and dust mites

MERV 5 – 8

Offers improved filtration, removing mold spores and dust particles from the air in addition to pollen

MERV 9 – 12

A good choice for anyone with mild allergies or respiratory ailments, eliminates auto emissions, pet dander and small airborne particles

MERV 13 – 16

Provides exceptional air quality, filtering out all the contaminants listed above along with mold, virus and bacteria spores

Do you have questions about furnace air filters? For expert answers and advice on HVAC system maintenance, turn to the highly-experienced professionals at Black Diamond Electric, Plumbing, Heating & Air.

Black Diamond Experts, serving homeowners in northern Utah, can help ensure that your HVAC system remains in good working order – and if yours is malfunctioning or inoperable, our repair services are quite affordable.

If you live in the greater Salt Lake City area or anywhere along the Wasatch Front, Black Diamond Electric, Plumbing, Heating & Air is your go-to source for emergency furnace repair and routine HVAC system maintenance. We’re here and ready to help with your furnace air filter needs – contact us today.