Most homeowners might think that an HVAC filter is the only way to improve the indoor air quality of their homes. However, Ultraviolet (UV) light within your HVAC system can kill a significant portion of germs, bacteria, viruses, and other pathogens.
If you're looking for an HVAC UV light for your home, it is vital to understand how they work, how much they cost, and how their various features and capabilities compare. Continue reading to learn more!
Disclosure: It is important you understand that we may receive commissions when you click our links and make purchases. For more info see our disclosure statement.HVAC UV Light Summary Table
Use this table to compare the best HVAC UV light options for your home. You can quickly make a comparison of each UV light's upfront cost, installation cost, specifications, and more.
Scroll past the table for detailed information on the best HVAC UV light options for your home.
What Does a UV Light Do In Your HVAC System?
Ultraviolet (UV) lights for HVAC systems purify the air within your HVAC system. How do they do that? It is actually quite simple; long UV bulbs inside your ductwork or HVAC unit produce UV-C light, killing germs, bacteria, viruses, mold, and other pathogens.
By reducing the number of pathogens within the HVAC system to nearly zero, UV lights improve indoor air quality. As such, they can make your home feel less stuffy, reduce respiratory irritation, and prevent the spread of infections.
For the most part, UV lights for your HVAC system are affordable and easy to maintain. However, many options are available with different pros and cons, which we will outline in our reviews below after explaining how the technology works.
Why UV Lights Work
Ultraviolet lights for HVAC systems produce a specific wavelength in the ultraviolet spectrum, UV-C. UV light is part of the larger electromagnetic spectrum, which also includes gamma rays, x-rays, infrared, microwaves, radio waves, and visible light.
UV light is between 100 nm to 400 nm wavelengths and has four distinct regions:
- Far UV- 100 to 200 nm
- UV-C- 200 to 280 nm
- UVB- 280 to 315 nm
- UVA- 315 to 400 nm
So, UV-C is just the wavelength range in the UV light spectrum that these HVAC lights use to disinfect your air stream. Interestingly enough, the light that reaches us from the sun is 95% UVA and 5% UVB, and no detectable amounts of UV-C from the sun ever reach Earth.
Therefore, you might be wondering why HVAC UV lights even use the UV-C range to disinfect the air. Well, the reason has to do with how UV-C affects DNA.
Both DNA and RNA absorb UV-C light and become inactive! In other words, when you expose germs, viruses, bacteria, and mold to UV-C for long enough periods, it will kill these pathogens and prevent them from replicating.
The UV-C wavelength of 200 to 300 nm just happens to be the sweet spot that disables and kills these nasty organisms.
How UV Lights Work
It is remarkable that something as simple as light can kill microorganisms, but how UV-C lights work is far from simple.
Info: HVAC UV lights look similar to the long fluorescent bulbs common in supermarket markets and office spaces. However, UV-C bulbs use a much more complex design.
UV-C bulbs contain a small amount of mercury vapor within the light tube, which is filled with argon gas at lower pressures, between 1 and 10 Pa. When you apply electricity to the bulb, it arcs through the argon gas and excites the mercury.
When mercury vapor gets excited, it emits UV light around 254 nm, the perfect germicidal wavelength for killing pathogens.
The UV-C light at this wavelength is not visible to the human eye. However, HVAC UV lights also produce light within the visible spectrum in a cool blue color.
Since HVAC UV-C lights disable the DNA and RNA of pathogens, it is helpful against bacteria, mold, coronaviruses, the flu, and E.coli.
Do UV Lights Produce Ozone?
UV lights do not produce ozone (O3). However, photocatalytic filters, sometimes paired with HVAC UV lights for additional air purification, can make a trace amount of ozone.
Having an air purifier produce ozone is troublesome and ironic because ozone itself is a toxic air pollutant!
But alas, all air purifiers (including the photocatalytic filters we'll touch on later) follow strict FDA guidelines. This means they always produce less than 0.05 parts per million of ozone, far below safe levels.
UV Lights Vs. Air Filters
Air filters and UV lights are effective methods of reducing contaminants in your air and improving its quality. However, you shouldn't use just one!
HVAC systems always need an air filter to remove dust and particulates from the air. UV lights do nothing to these types of particulates. They don't replace filters. If you did not have an air filter, your HVAC system would be recirculating lots of dust all throughout your home.
As such, you should still always use an air filter along with your UV light.
How UV Lights Are Installed
Installing a basic UV light with one bulb into your HVAC system is very simple. All you have to do is cut or drill a small hole into your ductwork and then attach the UV light's base with self-tapping screws or magnets.
Then, you slide the UV light tube (bulb) through the base and hole and lock it into place. Most homeowners can DIY install a UV light tube in an hour or less. It's just as easy as putting a straw in your fountain drink; it can't get much simpler.
On the other hand, more complex HVAC UV lights are a bit more tricky to install. For example, dual bulb UV lights, UV lights with photocatalytic filters, and smart UV lights that tie into your thermostat require additional installation steps and considerations.
For example, if you're installing a UV light designed for use near your evaporator coils or your whole house dehumidifier, you'll have to verify the dimensions to make sure it will fit.
How Often Do You Need to Replace the UV Bulb?
On average, UV bulbs last around 1-year of usage before you have to replace them. They typically cost between $50 to $110, depending on the model.
Most HVAC UV lights have a small sight glass so you can see if the bulb is providing light without having to remove it.
The Best UV Lights For HVAC Systems
It should be clear that UV lights for your HVAC system will improve your home's indoor air and combat the spread of viruses, germs, and bacteria. Plus, installing a UV light in our HVAC system is pretty easy to do yourself.
However, choosing the best UV light for your home can prove challenging. That is why we put together this list of the top seven units available after our detailed research and testing. There are many minor differences between each, with some including extra features and accessories.
HVAC Ultraviolet Light Comparison Table
HVAC UV Light Buying Guide
Determining which HVAC UV light is right for your home can be challenging. We put together some details on the best UV lights available above, but here are some things you should consider when making your selection.
Installation
Almost all HVAC UV lights take less than an hour to install, but some are more difficult than others.
Mounting and Drilling
All HVAC UV lights have to penetrate the wall of your ductwork or plenum. That means you will need a power drill and will have to cut into the duct wall with a circular drill bit. For some products, you'll even have to snip some sheet metal away with tin snips.
Since the single bulb devices just require a single hole, they are the easiest to install. The Bio Shield UV light even includes the drill bits to simplify installation. Dual bulb units are the next easiest to install; you just do the same steps twice.
On the other hand, HVAC UV-C lights with filters like the Honeywell UV Air Purifier with AirBRITE and D200 units require a bit more work. You'll not only need to drill, but you'll need the tin snips to cut away the square openings for the filters.
Powering
The easiest way to power an HVAC UV light is directly into a wall socket with a power cable. However, if you don't have an outlet near your HVAC unit or in a convenient location, a power cord could be an eyesore or a trip hazard.
The alternative is to power the UV light directly straight from a transformer within the air handler itself. That's precisely how the Honeywell UV2400U1000 and Honeywell UV Air Purifier with AirBRITE are powered.
Sure, hardwiring is another step and takes some basic electrical skills, but it prevents you from having a pesky cord going from your HVAC unit across the room to the nearest outlet.
Installation Location
Generally, you should install your HVAC UV light in two locations in your HVAC- under the coils or in the ductwork. If you are unsure where to install yours, you can consult with a local HVAC technician for help.
Ductwork Location
Installing an HVAC UV in the main trunk of your HVAC system will ensure that all of the air in your home blows past the light and gets disinfected.
Coil Location
An HVAC UV light operating near the evaporator coil of your air conditioner will disinfect all the air that blows through the HVAC system and prevent mold growth on the coils.
When the evaporator coils remove heat from the air, excess moisture condenses on them, making them the perfect environment for mold to thrive until you shine some UV-C light on them.
Length of Lamp Life
How long your UV light lasts is important to most homeowners- you probably don't want to buy replacement bulbs and replace them frequently. Thankfully, manufacturers of UV-C bulbs have, for the most part, maximized the lifespan of the bulbs to between 9,000 to 10,000 hours (around a year).
So, for the most part, all UV-C bulbs have around the same lifespan. However, if the light is not running 100% of the time, it will last longer- that's where some extra features can help.
Extra Features
Sure, an HVAC UV-C light on its own does fantastic work at disinfecting the air and decreasing the spread of pathogens in your home, but some extra features can make it even better.
For example, the photocatalytic filters on the Honeywell UV Air Purifier with AirBRITE and the D200 Dual Lamp Air Purifier remove VOCs and bad odors, making the indoor air quality of your home the best around.
Another useful feature is the energy-saving airflow switch on the OdorStop OS72PRO, which only turns the light on when the HVAC blower is on. There's no reason to "tan" the inside of your ductwork when the HVAC system isn't running, and this innovative unit recognizes that and saves you money on your energy bills.
Let There Be UV Light
There's no question that the UV-C wavelength kills over 99% of dangerous and contagious microbes; many studies show just that. And with the threat of COVID-19 still on many homeowners' doorsteps, it is a great time to take the plunge and update your HVAC system and improve your home's air quality.
