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.

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