Are UV Lights Effective for AC Systems?

Ultraviolet lights have been in use since at least 1903, when Nils Finsen was awarded the Nobel Prize for his work with UV lights in treating victims of tuberculosis.

Other uses for UV lights since have included serving as germicidal lamps in eating establishments, helping nail polish to cure more quickly, sterilizing water and, of course, killing germs in hospitals.

One other use for UV lights: Eliminating bacteria and mold in heating and air conditioning systems. But does the use of UV lights in AC systems really improve overall air quality inside one’s home?

According to one expert, that depends on the type of UV system installed as well as the priorities of indoor air in general. It does no good to install a germ-killing machine if you haven’t already covered basics such as sealing air ducts during renovation work and ensuring that all duct joints are sealed with mastic.

A pair of studies point to the effectiveness of UV light systems in eliminating bacteria and mold. One study, published in Science Daily, examined UV’s effectiveness at Duke Medical Center, where researchers eliminated drug-resistant bacteria in almost 50 hospital rooms. This brought down the number of bacteria by a reported 97%.

The other study, published in a U.S. government journal, took place in a commercial office building. After a period of 4months, the study says, “the fungal levels following UV operation were significantly lower than the levels in control AHUs (air handler units).”

Some of the benefits of using UV lights include the control of mold and bacteria; reducing blockages in condensate drains by curbing the growth of algae; and, cutting down on odors and smell.

Disadvantages include possibly eating away at the AC unit’s drain pan after a few years, as well as potential deterioration in the flex duct after only a couple of years of use.

More question about the best way to care for your AC system? Contact AC World today!