Most know mine and others setup by now. Small 887 ft condo, new ac/furnace.
The hallway closet right off the living room has a large return cavity below it.
It was making a helluva noise. I tried lining it with 2" 80% cotton roll from a soundproofing net site. It did wonders for the sound...only...it sucked up
the smell from that stuff.
I know DASH has reply posted about vanes and right turns...but that just doesn't work when the HVAC closet is practically in your lap.
I ran the AC and was gone for 4 hours...when I got back, I could "smell"
that "quieting" material I bought off the net. Natch. Whatever I line my
return cavity directly below my HVAC closet is going to transmit the smell of same
thruout my condo. Lesson learned (imagine what the smell will be like when I run my furnace). I will now do as many suggested here
and settle for lining that return cavity with nuetral smell plenum board/duct board.
Question: Duct plenum/duct board has silver paper on one side...fiberglass
in the middle..and a thin neutral smelling sound absorbing material on the
the backside. Instead of having the silver side out, should I reverse it and
have the sound absorbing part facing outward?
Also, In my zeal to quiet my hallway closet HVAC, I lined it (after they lined the closet with ductboard) with a closed cell foam blocking/absorbing material. Again..off one of those "sound absorbing"
net sites. Well...that stuff kinda stinks of "technology" as well. I may rip that out.
Most here deal with big homes and well established systems and ductwork.
Have pity on the small condo owner. Don't tell me that my AC company should deal with
noise..cause they just don't want to deal with it. I do.
Replies? Keep in mind my HVAC is in my lap...not down in a basement.