Many building engineers and contractors have recognized the IAQ, increased airflow and reduced maintenance benefits of installing ultraviolet germicidal irradiation (UV-C) systems in their and their customers’ HVAC systems.
However, it is the technology’s ability to slash 10 to 25 percent of HVAC energy use that drives nine-of-every-ten UV-C installations today. By eliminating accumulated organic materials and biofilm growth in commercial air handlers, the use of UV-C significantly improves airflow and heat-exchange efficiency levels, which can not only reduce energy use, but also decrease system maintenance costs and provide cleaner, healthier air. Although the benefits of adopting the technology are clear, UV-C equipment has traditionally proven difficult to size accurately.
Fortunately, as with most things today, there is an app for that.
If you’re a building maintenance supervisor or HVAC/R contractor, then chances are you’ve witnessed, or smelled, a fouled coil, or nasty microbial-laden plenums and drain pans. It’s worse when you actually know what that gunk is—a combination of bacteria carcasses, mold and fungi.
If you aren’t using UV-C equipment in your customers HVACR systems, you should change that right now. Virtually all HVACR systems are potential candidates for UV-C because of the key benefits it offers, including: (a) destruction of surface and airborne microorganisms; (b) the restoration and preservation of heat transfer and airflow capacities to "as-built" conditions; (c) greatly improved indoor air quality; and (d) reduced maintenance.
Lynyrd Skynryd was not singing about the smell dirty socks, but the refrain still applies, as some commercial and residential HVAC systems can smell like a high school gym locker, a phenomenon aptly named “Dirty Sock Syndrome.”
The smelly problem originates in heat pumps and HVAC cooling coils from dead, decaying microorganisms. Although different options exist for controlling these odorous occurrences, the most effective and practical is UV-C technology.
It seems like a daring claim: “add a low-cost, ancillary light fixture, and watch this magic bullet cut energy use, reduce maintenance and improve HVAC/R airflow and IAQ.” How could something so simple generate such striking results – is it true?
The quick answer is “yes”, more than true. Light in the UV-C wavelength (254nm) removes and prevents microbial buildup and growth as well as organic materials buildup. This buildup accumulates in all commercial air handlers to a greater or lesser degree and serves as an obstacle between the air and the cooling coils surfaces, thereby reducing heat transfer efficiency. Once this insulating material is removed, original efficiency and airflow levels return.