The scientific explanation for the purpose of germicidal lights, is basically, these UV lights deactivate the DNA of bacteria, viruses and other pathogens and thus destroying their ability to multiply and spread sickness. This Ultraviolet technology is a non-chemical approach to disinfecting your home’s ductwork. These lamps are designed to produce a certain dosage of ultraviolet light; usually at least 16,000 microwatt seconds per square centimeter, enough to destroy most airborne or surface bacteria, mold and/or virus. This principle approach is relatively inexpensive and requires minimal maintenance to achieve the beneficial results for your home.
Are there different types of HVAC UV Lights?
Yes, there are two types of UV lights for HVAC systems.
- Air Sterilization – A complete UV light unit that sterilizes moving air. The UV light unit is installed in the return air duct and works in conjunction with the cycles of the blower.
- Coil Sterilization – A “rod like” light installed inside the return air duct near coil. A coil sterilization UV light runs 24/7 and is the most common type of HVAC UV light.
What are the Effectiveness of these UV lights for your HVAC System?
Check out the links below for where two studies point to the effectiveness of UV light in killing mold and bacteria, one in hospitals and the other in a commercial HVAC system, then you can decided for yourself the effectiveness of these UV lights.
- Ultraviolet tight Effective in Hospital Infection Control – In 2012, Researchers at Duke University Medical Center used ultraviolet radiation (UV-C), which is knows for years to be harmful to microorganism. These UV lights nearly eliminate the toughest drug-resistant bacteria in 50 hospital rooms, reducing the number of bacteria by 97.9%.
- Effectiveness of Germicidal UV Radiation for Reducing Fungal Contamination within Air-Handling Units, this commercial office building, levels of fungi growing on insulation within air-handling units (AHUs) in an office building and levels of airborne fungi within AHUs were measured before the use of germicidal UV light and again after 4 months of operation. This resulted in significantly lower fungal levels following UV operation.
What is the cost of operation and how hard is it to maintain?
For example, if the unit is rated at 1.1 amps. To calculate annual energy costs, I used these handy calculators
- Convert Amps to Watts – 24v AC at 1.1 Amps = 26.4 Watts
- Convert Watts to Electricity Cost – 26.4 Watts * 24 hours/day * 10.5 cents kWh = $24.28 per year ($2.00 per month)
Now that we know it cost about $2.00 month to operate, the UV stick light bulb is estimated to last about 9000 hours or about 1 year. We do recommended that the bulb should be replaced during one of your scheduled HVAC Maintenance. AK AIRE offers our customers regular maintenance programs starting at $108 per year and with the program you can get up to a 15% discount on all parts for the life of your agreement. So, for under $20 a month your family will have the peace-of-mind knowing that you are breathing the highest-quality indoor air. It seems like a small price to pay. But it doesn’t make sense to install an HVAC UV light unless you’ve followed the indoor air quality priorities.
Here are some Indoor Air Quality Priorities you should take into consideration before adding in the HVAC UV lights. Even though UV lights are effective for killing mold, bacteria, germs and odors, make sure you have completed the indoor air quality basics to ensure you are obtaining the best Air Quality for your home. The basics priorities should include the following:
- Seal air ducts during renovation or construction
- Install ducts in conditioned space
- Ensure air-tight ducts, sealing all joints with mastic. See this Duct Sealing Guide from Building Science Corporation.
- Install high-MERV filters, but be sure your HVAC system is designed for the higher static pressure of better filtration
Install UV light in HVAC system
- Conduct regular maintenance, changing filters monthly and cleaning the coil annually
What are the Benefits and Disadvantages of HVAC UV lights?
Just like anything you choose to do, there are always some advantages and disadvantages you should be aware of. Ultimately, it is your decision on which products you choose for your home. Here are some benefits and disadvantages of installing a HVAC UV light.
Benefits HVAC UV lights:
- Control mold and bacteria
- Reduce colds and flus – germs are not re-circulated by HVAC system
- Reduce smells / odors
- Remove VOCs
- Are more effective in humid climates than dry climates
- Reduces clogging in condensate drain lines by preventing algae growth.
- Maintain a cleaner coil, improving cooling efficiency and reducing electricity costs.
Disadvantages of HVAC UV Lights:
Don’t clean flowing air unless air sterilization UV lights are installed
Destroy non-UV stabilized plastics in the air handler. Only items in the line of sight are affected
May eat the drain pan in 3-5 years
May eat flex duct in as little as 2 years
As with anything, there are several different types of HVAC UV lights on the market. We have included the most common one. Take a look over the list and find the one that best suits your needs. Just remember, the differences between Air Sterilization and Coil Sterilization. All in all, each brand pretty much does the same thing, they all help control indoor air pollutants in your home.
- Honeywell – (coil sterilization)
- Carrier Performance Series Germicidal UV Lamps (coil sterilization)
- Lennox Healthy Climate UVC Germicidal Lights (coil sterilization)
- Sanuvox (air sterilization, coil sterilization)
- TopTech Air Knight (coil sterilization)
- Guardian Air / REME (coil sterilization)
- Fresh-Aire (Triatomic Environmental) (coil sterilization)
- Trane – Perhaps their opinion has changed since posting Trane’s Position on UV-C Lights
Bottom Line, once you see your HVAC system as a whole, HVAC UV lights are an effective means for improving indoor air quality, but only after you take into consideration the system as a whole. The first step, is contacting AK AIRE to help you determine if your home is a great candidate for adding a HVAC UV light to your home. Once you install our HVAC UV light, you will experience healthier indoor air quality.