How To Install a UV Light in Your HVAC (Is It Easy?)

Are you interested in learning how to install a UV light in your hvac system?

You are in the right place.

We have created a step by step guide on how to install a UV light sanitizer to keep your hvac system free from mold and microbes.

In this article, you will learn..

  • Why you should always keep the UV light unplugged prior to the installation
  • How to determine the right location to place the UV light
  • How to use a hole saw to cut into the metal ductwork
  • The best way to power the UV light unit

UV light treatment systems have been around for decades.

Hospitals have been using UV-C light to inhibit bacterial growth backed by numerous scientific studies.

Keeping the inside of a furnace seems like an impossible task.

Fortunately, UV-C light is an invisible light frequency that is proven to stop the growth of microbes.

Read more to find out how to install these products to keep your air quality free from bugs…

Where To Install A UV-C Light Treatment System?

In general, you want to install a UV light treatment system so that the evaporator coil and drip pan get the most amount of light.

The most common locations to install a UV light is above the evaporator coil (A-coil), either side of the coil, or even inside of the coil.

However, if you plan on installing more than one UV light, you may want to install one bulb above the A-coil, and another towards the bottom of the air handler — near the drip pan.

It is advisable to remove the cover to the furnace, and take some measurements.

You don’t want to drill a hole in the sheet metal only to find out that the location won’t fit for the UV light bulb.

Also, if you have existing mold in your air handler, it is highly recommended that you first clean up the mold prior to installing the UV light.

Mold usually shows up on the interior ductwork of the air handler, inside of the blower fan, on the evaporator coil, the drip pan, and even the electrical wiring and manufacturer labeling.

A recent study has proven that UV light systems can stop the growth of mold in air handling units.

If there is existing mold, or there was mold, you may want to install the UV bulb in the area where most of the mold was growing because you know that that area is a mold hotspot.

Besides the location of where the UV bulb should be placed inside of the hvac system, you also want to keep in mind the exterior.

There has to be enough clearance on the outside to actually get the bulb into the unit. Some UV lights come with one very long bulb, which may be difficult or impossible to install in a small utility closet.

Keep in mind that most UV lights will need to be installed with the bulb in a horizontal position.


Read Also: How To Install a Solar Attic Fan (2019 Guide)

How To Drill A Hole For A UV Light?

Many hvac uv light products come with everything you will need to install a uv light — including a 3″ hole saw — except of course an electric drill.

If you bought a UV light without a hole saw, you will need to buy one so that you can cut a circular hole through metal ductwork.

It is important to first shutoff the power to the hvac system before installing a uv light — you don’t want to accidentally get shocked.

Locate the breaker at the panel box, and flip the switch.

Most UV light products will come with a paper template for the mounting.

Tape the template to the area where you wish to install the UV light.

Start slowly as you cut into the sheet metal, and as the hole saw makes a small groove, gradually push into the ductwork to cut the hole.

Read Also: Our top picks for the best UV light systems

best uv light for hvac

How To Mount The UV Light To The Furnace?

And now you should insert the UV light bulb into the hole that you just cut.

Do not plug in the UV light bulb!

UV light can burn skin and may damage your eyes.

After you insert the bulb into the a/c, most units will come with a few screws that you will use to secure the uv light system to the air handler.

How Do I Power The UV Light System?

With the UV light sanitizer secured to the furnace, now you want to power the system.

Most new UV lights such as the Honeywell will come with 5′-7′ long extension power cords.

All you will need to do is plug the unit into an existing outlet. Most utility rooms will already have an outlet.

Another option is to hardwire the UV light into the furnace.

You can even wire it so that the UV light only turns on when the furnace or a/c turns on.

Hiring an electrician or hvac contractor to do any custom electrical work is recommended.

How Do I Maintain the UV Light?

Most UV light bulbs will last about one year.

If there is blue light shining, this doesn’t mean that the bulb doesn’t need replacement.

The actual UV-C frequency that kills mold is INVISIBLE to humans.

There may be still blue light emanating from the unit, but it is no longer shining the UV-C light.

It is generally recommended to clean the UV light bulb every few months.

To clean the unit, you will need to take out the bulb, and clean it with a cloth.

You can use regular glass cleaning solution to clean the bulb from dust and debris.

Read Also: Do Whole House Fans Actually Work?

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Arie Van Tuijl

Arie Van Tuijl

Arie is a licensed home inspector who owns a residential and commercial inspection company in the state of Virginia. He also does specialty testing such as radon gas, termites, air quality, and mold.

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