Do Air Purifiers Work And Are They Worth It?

What Does an Air Purifier Do?

An air purifier processes indoor air using filtration or another air-cleaning technology. The exact process depends on the type of equipment.

For example, a mechanical filter captures airborne particles as air moves through filter media. Activated carbon can be used to address certain odors and gases, while UV technology may be incorporated into HVAC equipment for other indoor air quality applications.

Air purifiers can also differ in where and how they operate. Portable units generally treat an individual room or area, while whole-home air purifiers work with compatible HVAC equipment to treat air circulating through the heating and cooling system.

How Do Air Purifiers Work?

Air purifiers work by moving air through or past an air-cleaning component. What happens next depends on the technology the product uses.

Here are some common types of air purification and filtration technology.

1. Mechanical Air Filters

Mechanical air filters use filter media to capture airborne particles as air passes through them. These filters are available in different sizes, designs and efficiency ratings.

One rating commonly used for HVAC filtration is MERV, or Minimum Efficiency Reporting Value. MERV ratings provide information about a filter's ability to capture particles of different sizes.

For example, the Bryant Evolution™ Air Purifier uses MERV 15 filtration. Based on third-party testing cited by Bryant, the system captures 95% of particles from 1.0 to 3.0 microns.¹

The Bryant Legacy™ Line EZ Flex Cabinet Air Filter provides MERV 10 filtration and captures 63% of particles from 1.0 to 3.0 microns, with MERV 13 replacement filters available as an option.

2. Electronic Air Cleaners

Some air-cleaning systems use electrical technology in addition to or instead of conventional mechanical filtration.

For example, electrostatic precipitators electrically charge airborne particles, which can then be attracted to oppositely charged collector plates or other collection media. Depending on the type of system, these components may need periodic cleaning or replacement.

Because electronic air cleaners can differ significantly in their design, homeowners should review the specifications and maintenance requirements for the individual product.

3. Ionic Air Purifiers

Ionic air purifiers use electrically charged ions as part of the air-cleaning process. Depending on the design of the equipment, charged particles may settle on surfaces or be collected within the air-cleaning system.

As with other types of air purifiers, performance and maintenance requirements vary by product, so manufacturer specifications are an important part of comparing systems.

4. Activated Carbon Air Purifiers

Activated carbon addresses different indoor air quality concerns than mechanical filtration.

Instead of primarily capturing particles, activated carbon uses adsorption, a process in which certain substances adhere to the carbon's surface as air passes through it. Activated carbon is commonly incorporated into products designed to address certain odors and gaseous compounds.

Bryant incorporates carbon into its Preferred™ Carbon Air Purifier with UV. The system's carbon core is designed to help reduce common unwanted household gases and odors.

5. UV Technology

UV technology can also be incorporated into HVAC air quality equipment.

Bryant's Preferred™ Carbon Air Purifier with UV combines a carbon core with UV light. Bryant states that the UV light aids in reducing microorganism growth on the cooling coil and microorganisms released into the air.

This is an important distinction when comparing products: filtration, carbon and UV technologies perform different functions, so one technology shouldn't automatically be considered a substitute for another.

Do Whole-Home Air Purifiers Work?

Whole-home air purifiers work with compatible HVAC equipment to treat air as it moves through the heating and cooling system. This differs from a portable air purifier, which is intended to operate within an individual room or space.

How well a whole-home system fits your needs depends on factors such as the filtration or purification technology, your HVAC equipment and the specific indoor air quality concerns you want to address.

Bryant offers several whole-home options with different capabilities:

• Evolution™ Air Purifier: MERV 15 filtration that captures 95% of particles from 1.0 to 3.0 microns, based on third-party testing cited by Bryant.¹
• Legacy™ Line EZ Flex Cabinet Air Filter: MERV 10 filtration, with MERV 13 replacement filters available as an option.
• Preferred™ Carbon Air Purifier with UV: Combines a carbon core and UV technology to address specific indoor air quality concerns, including certain household gases and odors.

Whole-Home vs. Portable Air Purifiers

Deciding between a whole-home and portable air purifier starts with considering where you want the air-cleaning equipment to operate.

A portable air purifier is designed for an individual room or area. This can make portable units useful when air cleaning is desired in a specific space.

A whole-home air purifier integrates with compatible HVAC equipment and processes air as it moves through the heating and cooling system.

When comparing the two, consider:

• The area you want to address
• The type of air-cleaning technology
• Your existing HVAC equipment
• Filtration efficiency
• Installation requirements
• Filter and component maintenance
• Initial and ongoing costs

What Do MERV and CADR Mean?

When researching air purifiers, you'll likely encounter specifications such as MERV and CADR. They describe different aspects of air cleaning and shouldn't be treated as interchangeable measurements.

• MERV, or Minimum Efficiency Reporting Value, is used for HVAC air filters and provides information about a filter's ability to capture particles of different sizes.
• CADR, or Clean Air Delivery Rate, is used with portable air cleaners and represents the volume of filtered air delivered for specified particle types.

When comparing products, look at the rating appropriate for the type of air purifier you're considering rather than relying on a single specification.

What Can Air Purifiers Help With?

What an air purifier can address depends on its technology.

For example:

• Mechanical filtration is designed to capture airborne particles.
• Activated carbon can help address certain household gases and odors.
• UV technology may be incorporated into HVAC equipment for specific air-quality applications.

Because these technologies operate differently, it's important to match the product to the indoor air quality concern you want to address.

Are Air Purifiers Worth It?

Whether an air purifier is worth it for your home depends on your goals, HVAC system and the type of air purifier you're considering.

Before choosing an air purifier, consider:

• What you want the air purifier to address
• Whole-home vs. portable operation
• Filtration or air-cleaning technology
• Filtration efficiency
• HVAC system compatibility
• Filter and component replacement requirements
• Installation and ongoing maintenance

Instead of looking for a single technology that addresses every indoor air quality concern, compare products based on what each is specifically designed to do.

Do Air Purifiers Really Work?

Yes, air purifiers are designed to perform specific air-cleaning functions, but their effectiveness depends on the technology, product design and intended application.

A mechanical filter, for instance, isn't designed to perform the same function as activated carbon. Similarly, UV technology serves a different purpose than particle filtration. Understanding these differences can help you set realistic expectations and select an air purifier that aligns with your home's needs.

For homeowners interested in a whole-home solution, your local Bryant dealer can review your existing HVAC equipment and discuss compatible air purification and filtration options.

¹Based on third-party testing (2012) showing 95% of particles size 1.0 to 3.0 microns captured.