The Environmental Protection Agency states that indoor air can be more polluted than outdoor air. Because most people spend approximately 90% of their time indoors, maintaining indoor air quality is important. One of the best ways to keep your air clean is to install a germicidal UV light inside your HVAC system, usually close to the coils in the air handlers where there is typically a lot of moisture. The certified technicians at Ellington Air Conditioning & Heat have the expertise to help keep your indoor air fresher, healthier and cleaner.

Ultraviolet light is not visible to the human eye. UV light waves are classified into four levels that range from 0 to 400 nanometers. Short-wave UV light, UV-C, ranges from 280 to 200 nm, which inactivates germs, including bacteria, viruses, and fungi. In HVAC systems, professionally installed UV germicidal lights can help eliminate viruses and other microorganisms from the indoor air.

In 2020, the SARS-CoV-2 virus has become a pandemic, spreading by direct contact and through droplets and aerosols circulating in the air. Ultraviolet germicidal irradiation, along with improved ventilation and better filtration in HVAC systems, helps prevent germs from spreading through buildings.

In ducted HVAC systems, conditioned air is routed back into the system through return air ducts. This air can contain bacteria, viruses, spores, dust, and other airborne pollutants. Germicidal UV lights are often installed inside HVAC systems to limit the growth of microorganisms on air conditioning coils and in the air flowing in ducts. The placement and intensity of the lights affect its effectiveness in deactivating harmful organisms.

Coil sterilization lights are aimed at coils and drip pans to reduce bacteria, viruses, and biologic particulates on these wet surfaces. These lights stay on 24 hours a day. According to the Lawrence Berkeley National Laboratory, UVGI lights that irradiate surfaces within the system are 99% effective.

Air sterilization lights are installed in the return air duct and irradiate airborne microorganisms present in the air routed from the living space back into the air conditioning unit. A highly reflective surface within this area of the ducts intensifies the light and boosts the effectiveness. These lights work when the air handler is on.

The effectiveness of HVAC UV light to deactivate airborne germs depends on the speed of airflow, amount of moisture in the air, and type of organism. Good-quality filters work with these lights, capturing particulates that may contain microorganisms.