How UV Lights Can Improve Your Air Quality

What is a UV light?

Ultraviolet (UV) lights can be used to kill microorganisms such as viruses, bacteria, mold and fungi. They first found commercial popularity for use in water treatment facilities to remove mold, mildew and other biological contaminants from water and surrounding equipment. The technology was then introduced into the HVAC market in order to help prevent the spread of infectious disease in hospitals, doctor’s offices and other medical facilities. As a result of its effectiveness, it has become more widespread in both commercial and residential HVAC applications. 

How do UV lights for HVAC work?

In residential applications, we typically install the UV light (commonly referred to as a “stick light”) near the coils to prevent mold or bacterial growth. In addition to killing organic growth on the surface of the coil and housing, the UV light can also sanitize the air that crosses its path. With adequate exposure, the light can kill airborne bacteria, mold, fungi and some gases without restricting airflow. Because air must come into close contact with the light in order to be decontaminated by it, it has a less immediate effect on indoor air quality throughout the rest of the space. 

For this reason, we also recommend installing UV light system in the supply side of the unit (in the ductwork) to further treat the air as it leaves the coil and eliminate any mold growth on the outside of the coil and supply plenum. It also releases hydroperoxides that actively attack viruses, bacteria, mold, VOCs, odors, allergens and other particulates/contaminants throughout the entire conditioned space. 

HVAC UV light maintenance and safety

UV lights must be replaced every one to five years. The frequency will depend on the manufacturer’s recommendation for your particular model. Even though the light may still be on and visible, the effectiveness of the UV light declines drastically after the recommended useful life expectancy .