Dampness in AC air handler closet
I’ve got a damp air handler “closet” that has a mildew smell. I’m looking for a good solution to the moisture. I think the source of the moisture is the air handler itself — it’s a cold surface in a warmish area of the house in a hot-humid climate (south Louisiana), and water condenses on the outside of the unit. I had a condensate line leak recently, which has been repaired, and I realized then that the space is always muggy inside.
I can put insulating board on one or two faces of the air handler, but the top and two other sides are inaccessible and would still sweat. The space is probably too small for a dehumidifier — about 3′ wide, 5′ deep, 6′ high. If not for the smell, I’d just add a small supply air or put a passive vent in the door, but it’s too musty in there. Venting to the outside is possible but not easy, and I think and exhaust vent in my climate would just bring in wet air to condense somewhere else. Is something like Damp-Rid the only solution, or am I missing something?
FWIW, the “closet” is really just an unfinished space, with air handler, ductwork, exposed studs, etc. It’s within the building envelope, surrounded by conditioned spaces on all sides. Thanks!
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