It was 1996 when UVC light was filrst installed in an HVAC air handling unit as a method to have 24x7 coil cleaning. Since then this application has become widesread and is even a standard item in the GSA new construction specification. Now with widespread distribution and many manufacturers now offering different sytems the price to install these systems has fallen so much that most of the time they pay for themselves in less than a year! Even in cold Northern Climates like Minnesota, North Dakota, and Wisconsin.
So how does a lightbulb keep your HVAC coils clean? It's a fancy lightbulb! More seriously it has been known for over 125 years that some wavelengths of light have germicidal properties, with UV-C at 253.7 nanometer wavelength being at near the apex of this germicidal effect on the dna helix of microorganisms. Your coils are a perfect environment for microbial growth, and once it starts it multiplies and and spread quickly - making heat transfer go down and require more energy to do the same amount of work.
But we do regular scheduled coil cleaning!
Great, but with UVC light installed in your HVAC air handling system you won't need to anymore because you can install it and then let the light do the work for you. This ensures that the coil not only gets completely clean, but also stays that way. When you do coil cleaning with chemicals, compressed air, pressure washer, or whatever message you may use it is only temporary! Becasue the UVC light systems are designed to operate 24 hours a day and 7 days a week your not only get the coils clean, but keep them that way.
Keeping the coils clean means they will stay operating at or near system design, which is their most energy efficient state. What's more is that newer UV light systems are quick and easy to install - usually in less time than you would spend cleaning the coils in the first place!
You have a pair of AHUs supplying 40,000 cfm and the system operates for only 3,000 hours annually. With the increase in heat transfer and lower static pressure across the coil due to having it clean all the time results in $7,629.00 annual savings at delivered energy cost of 10 cents per kWh. Raw materials is estimated at about $5,000. Three hours to install each system, so 6 total hours at $100/hour is anouther $600. Plus the electrical cost of having the T5 UV-C emitting lamps on is $1,093 annually. This results in a payback of 11 months, with the following years netting $5,536 in energy cost every year thereafter. Plus you can add in that the maintenance staff is no longer having to spend time and money cleaning coils - so they can focus and complete more important tasks!
For a detailed Return-on-Investment for your specific AHU or facility visit our Quick ROI Calcutaor for a Payback Estimate with your variables!