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UV Light for HVAC: Do they Work?

UV Light for HVAC: Do they Work?

UV HVAC light systems, also called germicidal air purifiers, can effectively sterilize almost 100% of germs, viruses, mold spores, bacteria, fungi and other harmful microorganisms as they pass through your HVAC system. Installing a UV HVAC system in your condensing (indoor) unit provides a cost-effective method to clean your home's air as it passes through the system.

To help you decide if a UV HVAC light is right for your home, we'll go over:

  • How UV HVAC lights work
  • Benefits of an HVAC UV light system
  • UV HVAC air purifier limitations


Want a quote to install a UV HVAC air purifier? Call Reliable Heating & Air at (770) 594-9969 or schedule an appointment.

Our HVAC techs can recommend the best germicidal air purifier for your home. You'll also get the same 5-star customer service we've been giving Atlanta residents for the past 40 years.


How UV HVAC Lights Work

Germicidal UV HVAC lights are designed to rid your home's air of impurities. UV air purifiers use UV-C light (a light wavelength of 254 nanometers) that's absorbed by the DNA of microorganisms.

The UV light doesn't immediately kill the organisms, but renders them unable to produce the proteins they need to survive and reproduce. This prevents them from causing harm and shortens their lifespan.

Types of HVAC UV light systems

You can choose between 2 types of UV lights for your HVAC system:

  • Coil sterilization: These types of UV air purifiers are mounted inside the air handler near the evaporator coil. The UV-C light is on 24/7 to prevent microbial growth on the evaporator coil and sterilize contaminants as they pass through your HVAC system.
  • Air sterilization: Installed in the return air duct, this kind of HVAC air purifier is wired to your HVAC system so it turns on only when your system is running and sterilizes air before it gets pulled into your system. Since it purifies all air passing through your system, the UV air purifier also helps sterilize HVAC components near the purifier.

Installing HVAC air purifiers

Only a professional HVAC technician should install UV lighting inside your system's evaporating unit. The technician will need to:

  • Install the air purifier properly, so it operates safely. Extensive exposure to high doses of UV-C light can be harmful to people, so it's important that only a trained professional installs your HVAC air purifier.
  • Wire the air purifier to your HVAC system (if you opt for air sterilization), so it turns on when your HVAC system does.
  • Clean the air handler system thoroughly and inspect the ductwork for leaks, so dust and debris aren't being sucked into your HVAC system.

This will ensure your HVAC air purifier system will perform efficiently as it should, so you enjoy all of the benefits.


Learn more about our HVAC UV light products on our UV light installation page.
Learn more about our HVAC UV light products on our UV light installation page.

Benefits of an HVAC UV Light System

Installing a germicidal air purifier will:

  • Restrict mold and mildew growth. Your AC creates a very damp environment that mold and mildew thrive in. By installing a UV air purifier, it will prevent mold and bacteria from growing in and spreading throughout your HVAC system.

  • Remove volatile organic compounds (VOCs). VOCs are organic chemicals that have strong vapors at room temperature. Common household VOCs that HVAC UV light systems neutralize include paints, solvents, aerosols, cleaners, disinfectants, repellents, and air fresheners.

  • Eliminate viruses and bacteria. HVAC UV lights sterilize viruses and bacteria before they can be recirculated back into your home, which helps reduce airborne germs that can infect healthy family members or those with weaker immune systems.

  • Help your AC run more efficiently. When bacteria (from dust, VOCs, or mold growth) builds up on the evaporator coil, it prevents adequate airflow, which can cause your air conditioner to ice up. By keeping bacterial growth off of your evaporator coil, your AC will run more efficiently and help prevent expensive repairs.

While UV lights in HVAC systems are effective at sterilizing contaminants and allergens, they do have some limitations.

UV HVAC Air Purifier Limitations

Doesn't remove allergens

While germicidal air purifiers sterilize your home's air, they don't actually remove the microorganisms. That means if you have allergies, they may still bother you since the dust and other contaminants are still present.

UV HVAC light systems are most effective when paired with another type of air filtration system. Most Atlanta homeowners pair germicidal UV lights with an air filter that has a high MERV (minimum efficiency reporting values) rating. The higher the MERV rating, the more effective the filter is at removing small contaminants.

Your average 1-inch fiberglass filter has a MERV rating of 1-4, which means they can capture roughly 20% of contaminants 3-10 microns in size. The most effective air filters on the market are high-efficiency particulate air (HEPA) filters, which have a MERV of 17 and can remove 99.9% of contaminants 0.3 microns in size.

Requires UV light contact

UV air purifiers are only effective if the microorganisms pass through the UV-C light inside your HVAC system. That means if your HVAC system has damaged or leaky ducts, the holes or gaps in the ducts can create a vacuum that draws in new contaminants (like dust and debris) from attics and crawl spaces—which don't pass through the UV light and so don't get sterilized.

Regardless of whether you install an HVAC air purifier, you'll want to get a duct sealing to make sure your ducts don't have any holes, tears or gaps that can let contaminants in or conditioned/heated air out.


Want to Install a UV HVAC light? Call Reliable Heating & Air.

Call us today at (770) 594-9969 or schedule an appointment for a free in-home estimate.

We offer the most reliable UV HVAC light installations in the Woodstock area. Our HVAC techs will explain the pros and cons of a germicidal UV light and other air filtration systems, and then give you a free quote to install one in your HVAC system. We'll help you improve your home's air quality in no time.

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