Ultraviolet light has long been used in water purification and to sterilize hospitals and medical equipment. Nowadays, more and more people are also turning to UV lights for air purification to help improve the air quality in their homes. This article will explain how UV light purification works and what benefits it can provide to your home to show you why it can be such a good investment.
How UV Light Purification Works
Certain wavelengths of ultraviolet light have extremely powerful germicidal and fungicidal properties. That means that UV light destroys bacteria, viruses, mold, and fungal spores. The type of light used in air purification systems and units is high-frequency, short-wavelength UV-C. This wavelength is the most effective since it produces radiation that damages the nucleic acids that makeup DNA and RNA. The light doesn’t kill bacteria and other microorganisms, as some people believe, but exposure to UV-C light severely damages their DNA. As a result, they instantly lose their ability to reproduce and become harmless.
UV-A, UV-B, and UV-C light or radiation are all emitted by the sun. Approximately 95% of the light that reaches the earth is UV-A. The other 5% is UV-B, which is what causes sunburns. However, the atmosphere blocks most of the short-wave UV-C light that the sun emits. That’s why it’s so powerful and harmful to microorganisms since they aren’t accustomed to being exposed to this specific type of UV radiation. UV-C radiation is also extremely harmful to humans, but UV light purifiers are safe since the light shines inside your HVAC system.
UV light purifiers can be installed as part of any central heating and cooling system and work to eliminate mold, bacteria, and viruses within the system. In this way, the UV light unit prevents all microorganisms from spreading around the house whenever your HVAC system is running. UV light purifiers are most effective at combating bacteria and fungi. They are less effective against viruses, partly because most units aren’t powerful enough to destroy most common viruses. Some UV lights are powerful enough to destroy any virus, but they usually cost several thousand dollars and are mostly used in hospitals and labs.
Different Options for UV Light Purification
Two types of UV light units are designed for use in central HVAC systems. Although the purpose of both is to eliminate mold and bacteria, each one is intended for a different use. The first type is an air-sanitizing light. As the name suggests, this type of unit works to eliminate mold and bacteria and purify the air circulating through the ductwork system. They can be installed on either the return or supply side of the duct system and are directly wired into the HVAC system’s control board. That means it will automatically turn on and off as your heating or air conditioning does. Some stand-alone whole-home air purification units have the same type of UV light that serves the same purpose and works in tandem with mechanical filtration.
The second type of unit is typically referred to as a coil-sanitizing light. This type of unit serves a specific purpose: to prevent mold and bacteria from growing on a central AC system’s evaporator coil. The evaporator coil is what enables the refrigerant in an AC system to remove heat and cool the air flowing through the system. This coil is extremely cold when the AC is running, which means that water vapor in the air condenses when the air meets the coil. That means that the coil is constantly wet whenever the AC is running. Combine that moisture with the warm air coming into the system, and it creates conditions that can sometimes allow mold, algae, and some types of bacteria to thrive. When mold, algae, and bacteria are present, a cooling system will spread them through a house. This situation decreases a home’s air quality and can result in the conditioned air produced by the system having a moldy and musty odor. A coil sanitizing light can help eliminate odors if this is an issue you are dealing with when your cooling system is working hard to keep your home comfortable during the dog days of summer.
A coil-sanitizing unit is mounted in the air handler compartment so that the UV rays shine directly onto the evaporator coil and the drain pan below it. Having the light shine on the drain pan is especially helpful since this part of a central air conditioning system is typically most prone to mold and algae issues. Instead of turning on and off with the AC system, this type of light stays on 24 hours a day. This is to ensure that no issues arise during periods of cooler weather where the AC doesn’t need to run much or at all. With this type of unit, you’ll need to turn it on in the spring or whenever you first start using your air conditioning and shut it off at the end of the summer.
An added benefit of installing a coil-sanitizing light is that it can help your air conditioning system work more efficiently and cool more effectively. That’s because you can sometimes end up with a film on the evaporator coil that’s made up of mold and algae that have accumulated over time, and this build-up can make it so that the refrigerant can’t absorb as much heat.
How to Know Which Type of UV Light Purification Is Best for Your Home
Coil-sanitizing and air-sanitizing lights each have their own advantages, and it can sometimes be challenging to know which one is the better choice for your home. A coil-sanitizing UV light is better for preventing mold from growing in your cooling system. However, it only works for part of the year whereas an air-sanitizing light will help to purify the air in your home throughout the entire year.
If you choose to install a coil-sanitizing light, there’s no point in keeping it on all year since it would just waste energy without having any effect on your indoor air quality in winter. This is because the way the light is positioned means it won’t eliminate mold and bacteria from the air your heating system circulates around your house.
The best option is to combine UV lights with some other type of air purification or filtration equipment. Mechanical filtration allows you to tackle allergens and pollutants like pollen, dust mites, and volatile organic compounds to improve the air quality in your home.
Contact the Pros
Universal Heating & Cooling has been the leading HVAC company in Springboro, Springfield, and the Dayton area since 1976. We specialize in UV light purification and also offer a range of other options for improving indoor air quality. Our experienced technicians are also ready to help if you need any air conditioning or heating service. For more information on the ways we can help improve the air quality in your home, contact us today.
