Informational Guide

How to Install UV Light in HVAC?

We elaborate on how to install a UV light in an HVAC system for a healthier home. Learn about the complex background of UV lighting in AC units & heating.

by Josh M

The simple thought of bacteria, mildew, and mold multiplying in your HVAC is worrying to someone who wants a clean, sanitized house.

Perhaps the biggest issue with a compromised HVAC system is that it’s bad for you and your loved ones’ health, especially for those with severe breathing problems such as COPD or asthma.

It’s a well-known fact that UV lights can effectively sterilize equipment and indoor air. It is practical, efficient, and thorough.

If you’re new to the idea, you must be wondering about the cost to install a UV light in AC or furnace, how they are installed, and if they are even worth the investment.

Read on as we elaborate on how to install UV light in an HVAC system for a healthier home:

UV light, aka Ultraviolet light, is the electromagnetic radiation on the low-end of a light spectrum. Also, roughly 10% of the output of the Sun contains UV light.

HVAC UV (Ultra-violet) light is a bulb that radiates the UV light to eliminate mildew, air-borne viruses, and mold.

One key advantage of short-wave UV light is that it sanitizes surfaces. When used in HVAC systems, it can help you sanitize indoor with its bacteria elimination properties.

2 Types of UV Light Explained

UV lights are also called sanitizing lights, germicidal lights, purifying lights, and, of course, sterilization lights.

Nevertheless, there are two kinds of UV lights – coil and air sterilization – available to sterilize your air conditioning and heating systems.

Coil Sterilization

If you’ve got a central air-conditioning system, it means yours is an indoor coil. It is known to be the central location for bacteria and mold development. Why?

That’s because a coil is utilized to condense humidity from indoor-air to dehumidify the house during air conditioning.

The moment air passes through the coil, a range of debris such as pet dander, dirt, etc., sticks to the wet surface. It’s the perfect condition for bacteria and mold growth.

Coil UV lights are commonly used in HVAC systems. You can also find both dual-lamp and single-lamp models.

These lights are set up strategically to shine on the coil’s surface continuously.

Air Sterilization

The air sterilization UV lights are set up in the duct system or ductwork, taking the return air back.

These UV lights are placed to kill mold and air-borne germs. You’ll find them commonly in U-shaped and stick lamps.

Some air purifying lights are connected with a blower motor. They switch on and off along with the HVAC system. Since they are hardwired together, the cost of installation is pretty high.

Benefits of HVAC UV Lighting

If left uncleaned, your HVAC system can distribute debris, allergens, and strange odors. However, by installing UV lights in the HVAC system, you can eliminate carbon-based waste.

Here are some benefits of HVAC UV lighting:

Lessens Risk Of Sickness And Allergies

Allergies and illnesses can spread rapidly through a compromised HVAC system.

However, with the correct placement, UV lights can eliminate many micro-organisms that lurk within your system’s air-ducts and coils.

Gets Rid Of Odors

HVAC systems are safe havens for odors of burned food, paint, tobacco, etc., throughout the house. While some scents can be annoying, others can be dangerous for human health.

Fortunately, UV light can help eliminate these organic compounds from indoor air so that you and your loved ones can breathe fresh air.

Improves Airflow And HVAC Efficiency

With time, your HVAC system becomes vulnerable to germs, pollutants, and dirt, which will reduce efficient output.

Cooling and heating systems with compromised performance will have to work harder and longer to achieve the desired result, making them weaker over time.

Not just that, but the increased energy use will drive your monthly utility bills up.

But if you choose UV lights for your HVAC system, they will ensure that the coils remain clean and add approximately 10 to 35% power back to the system.

Cost-Effective Investment

When you install UV lights in your HVAC system, it will keep it clean. It’s a cost-effective investment if you consider the health and money-saving advantages it offers.

It’s also one of the cheaper HVAC cleaning options.

Factors to Consider When Choosing UV Lights for HVAC

UV lights come in various sizes and shapes, so before you make a purchase, consider the factors below:

UV-C Output Power

Though efficiency is crucial, you shouldn’t overlook the strength of the bulb. That’s because large houses, large duct systems, or aggressive dirt and mold need a more robust light.

Since moisture and air circulate throughout the house, mold growth can happen anywhere in the AC system. The lights you choose should wipe out all microbe irrespective of how prevalent it is.

Power Consumption

With strength, you should also consider efficiency as the two balance each other.

You don’t want either an ineffective UV light or one that is so strong that it increases your electricity bill to the point where you have to turn it off periodically.

Therefore, finding the balance between the two is vital. Pay attention to the lights’ design, consider the watts capacity and the reflector technology to make the best decision.

Light Bulb Replacement

With the efficient bacteria eliminating properties, it’s very easy to ignore that they are simple lightbulbs; hence they will ultimately burn out.

This is why it’s crucial to consider bulbs that are easy to source, well-made, and don’t need to be replaced too frequently.

How To Install UV Light For HVAC: Step By Step Guide

Follow this step by step guide on how to install UV light in HVAC system:

  • Pinpoint the best place to install HVAC UV light: The most crucial step in installing the UV light is setting it up. Install it in an area it will be effective and eliminate most mildew and molds.
  • Drill hole(s) for UV light: Drill holes in your metal HVAC system’s cover to help UV light seep through. You can drill holes about 1-1/2″ in diameter.
  • Screw and secure the UV light to your furnace: Take the screws and tighten the UV light case with the AC unit. Make sure you don’t tighten screws too much as it may damage the plastic housing of the UV light.
  • Turn the UV light power on: Once the light is tightened, switch it on. The easiest way is to plug the light into a standard 120V outlet.
  • Regularly change and clean the light bulb: Once it’s installed, you’ll have to change the bulb annually or every three years. Also, make sure to clean them for efficient service.

People Also Ask (FAQ)

How Do You Install UV Light For Water Treatment?

Here are the steps on how to install UV light for water treatment:

  1. .First, decide where you want to place the filter
  2. .Mount the UV light housing to a wall
  3. .Undo both ends of the UV light housing and then seal it up
  4. .Connect light to the waterline
  5. .Turn on the water
  6. .Plug UV system in the wall

You can also watch this installation video

How Much Does It Cost To Install UV Light In AC Unit?

The installation cost of UV lights varies. For example, if you have coil sanitizing lights, they will cost between $60-$285, and the installation cost will be anywhere between $100 to $230.

However, if you want to purchase air sanitizing lights, it will cost you around $80 to $400, and the installation cost will be from $150 to $295.

Are UV Lights In HVAC Safe? Does HVAC UV Light Cause Cancer?

Direct exposure to the UV-C lights in your HVAC system is risky and detrimental to your body, especially to the eyes and skin. Except for the UV-C radiation that causes cancer, no other UV light type is as harmful.

How Long Do UV Bulbs Last?

Usually, UV bulbs should be changed every year or every 9000 hours, to be precise.

Can You Touch A UV Bulb?

No, you can’t. Avoid touching the glass section of the purifying UV bulb with your bare hands, as it can burn your skin and cause severe eye damage.

Where Is The Best Place To Install HVAC UV Light?

The best place to install HVAC UV light is in A-shape above, down, or center to the coil, as it allows maximum exposure to the coil.


Hopefully, now you have enough knowledge on the importance of UV lights for your health and HVAC system. Plus, with the instructions above, you now know how to install a UV light in HVAC.

Your HVAC systems are susceptible to dirt, mildew, molds, and other bacteria that can harm your health by polluting indoor air.

To ensure you get clean and fresh breathing air, install a UV light in your HVAC system.

Josh M

My name is Josh and I am obsessed with the HVAC industry. I created this website to help HVAC techs of all levels get the best out of their heating & cooling systems. I have spent thousands of hours studying air conditioners, heaters and home air products so you can learn & buy with confidence. Learn more about the team here.