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Will UV light in the a/c stop mildew/mold from growing in the plenum?


Premium Member
Jan 7, 2014
United States
Model Number
1-5 years
Our last plenum was not sealed in several places and grew mold on the internal insulation. We had a well-known company install a new plenum and it still leaks in the back of the plenum. Long story short, the plenum is too close to the wall to just tape it perfectly and mastic it. I had two companies come and try to seal it from the inside and it didn't work so now I know it is open and I hope it doesn't mold again.

The first company that installed the a/c before we moved in screwed us over by setting it too low so it is hard to put the filter in. The HVAC company wants about 1600 to lift it and seal it all perfectly. The well-known HVAC group said installing a UV light would stop the mold from growing on the internal insulation if it were to happen again.

Either way, the a/c is blowing much better in every room but I don't have the money to have it lifted/moved away from the wall and properly sealed.