As the country continues to recover from the pandemic, air quality remains the number one priority for facility owners, managers and operators looking to assuage the concerns of occupants and visitors to their buildings. As part of this, an increasingly popular solution, particularly within HVAC systems, has been Ultraviolet Germicidal Irradiation (UVGI) that uses shortwave ultraviolet (UVC) radiation. The only question then is: how effective can UVC be when installed in HVAC systems?
The ASHRAE and CDC both heavily recommend these systems as a means of airborne disinfection, but not knowing where, or how to install these technologies can severely hamper their performance. When done properly, not only can these technologies vastly improve indoor air quality, they can also help mitigate costly cleanup of HVAC components, and also vastly increase the energy efficiency and heat exchange rates of these systems in buildings.
Steve Gitkin from AHR News outlines some of the best practices facility owners, managers and operators can use and what they can expect when installing UVGI technology into their HVAC Systems.
Understand the Optimal Install Location
For the most effective microbial control, Gitkin writes, the device should be installed on the supply side of the system, above the drip pan. This way, the location allows it to provide better biofilm and microbial control than inside the system by irradiating contaminants at the source, while also disinfection surface and airborne microorganisms.
Maximize Chiller Performance
Since UVC can eliminate biofilm and other organic build-up on cooling coils, it helps maximize heat transfer, allowing the chiller to operate under optimal conditions. Eliminating build-up between the fins also increases air flow. As such, less energy is needed to push air through the system, cutting down on energy usage.
Cut Cleaning and Health Hazards
As part of the energy-savings, UVC will also reduce the need to clean HVAC systems. When installed on the supply side, Gitkin notes, it will eliminate the need entirely. It also will reduce the need to use harsh, toxic cleaners in the HVAC environment.
Make a Sustainable Impact
Being able to cut down on energy costs and carbon emissions alone add great value to any UVC installation. As such, many UVC project, Gitkin advises, may qualify for government incentives, utility rebates or even tax reduction.
A recent trialing of UVC installations further underscores its effectiveness. Following one such installation, researchers found a greater than 10% gain in net cooling capacity with an 8.6-11.8% reduction in cooling pressure drop.
Additionally, there was an up to 4.7% increase in airflow, a 99% reduction of microbes on coil and HVAC surfaces and an up to 99% reduction in microbes from air and AHU supply air samples.
However, Gitkin notes that no two HVAC systems are alike—and decision-makers should adopt a UVGI or UVC implementation strategy that suits their needs best in order to protect people in the places where they live, work, and play.
