UV Lights


A quick note about UV lights: they work like sunlight in that they prevent and kill many types of bacteria and fungi when exposed to the light on surfaces. They do not generally do a great job of killing spores suspended in the air stream.

UV lights are great at killing yucky stuff on surfaces like coils, blower wheel, and panels. They won't “kill” everything in the airstream, and they don't capture anything.

Also, be careful about what the UV is allowed to shine on. It will deteriorate most wire insulation and can deteriorate and discolor many other plastics.

Finally, don't look at a UV light for any amount of time. I once spent a very uncomfortable day in bed after damaging my eyes from looking at UV indirectly for only a few minutes.

UV can be great, but it's not a fix-all. Always be careful as to where the light is going.

—Bryan

2 responses to “UV Lights”

  1. Thanks for that bit. I have some coils that have mold on them this might help.

    • This is all correct. To add a couple of things. If the UV lights are mounted in such a way that the light hits carpet, it will bleach it.

      As for what it does or doesn’t kill, that is important. Also important is what do you do after the lights “kill” the “bugs” – are they safer dead or alive? Depends on what it is. You should follow this up with good filtration to capture what you killed. That of course opens a whole other conversation on filtration and the effect if has on static duct pressure.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Related Tech Tips

Start Capacitor & Inrush Facts and Myths - Part #1
This series of articles is one of those that will bug a lot of people because it will go against a lot of what you've been told about compressors, start capacitors, and inrush current. For that reason, I want you to work through a few thought experiments first and maybe even stop and try it […]
Read more
An Electric Heat Mistake
I started working as a tech when I was 17 years old, fresh out of trade school. My first winter out on my own, I went to a service call in an older part of Orlando, a part of town I had never worked in before. It was an especially cold winter that year, and […]
Read more
Why Measuring Static First Isn't Always Productive
There is a big move in residential and light commercial HVAC toward measuring static pressure regularly during commissioning, service, and maintenance. Don't get me wrong… Measuring static pressure is VERY important. The challenge comes in when techs begin taking measurements without understanding where to take them, what they mean, or worse: they use measurements as […]
Read more
loading

To continue you need to agree to our terms.

The HVAC School site, podcast and daily tech tips
Made possible by Generous support from