Air Conditioning - Condensation/Sweating interior duct
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millercv
08-04-09, 10:05 PM
I've done some searching but not found something exactly like this so here goes.
I noticed a musty smell coming from a closet that has the AC duct that goes from our crawl space to the attic (two story house). There was an access panel there that I had never opened before and when I did - sure enough the duct was obviously sweating/covered with condensation. The insulation was pretty much wet all the way through.
I found a small panel to access the shaft on the second floor and it does feel damp up there also. I then checked the duct in both the crawl space and the attic and they were dry. So it is just the "inside house" portion.
I've got the panel open and a fan blowing in for the moment and it has already dried up a good bit (but still has a ways to go).
One thing I did discover is right inside the access panel was a damper control that was set to 50%. It has always been a good bit hotter upstairs so I opened it completely and can now feel a bit more cold air coming out of the upstairs vents. Would this have anything to do with it? Also in a general damper question since it is new to me - I would assume it would be ideal to open it completely in the summer and close it a bit in the winter since hot air rises.
Thanks for any help!
I noticed a musty smell coming from a closet that has the AC duct that goes from our crawl space to the attic (two story house). There was an access panel there that I had never opened before and when I did - sure enough the duct was obviously sweating/covered with condensation. The insulation was pretty much wet all the way through.
I found a small panel to access the shaft on the second floor and it does feel damp up there also. I then checked the duct in both the crawl space and the attic and they were dry. So it is just the "inside house" portion.
I've got the panel open and a fan blowing in for the moment and it has already dried up a good bit (but still has a ways to go).
One thing I did discover is right inside the access panel was a damper control that was set to 50%. It has always been a good bit hotter upstairs so I opened it completely and can now feel a bit more cold air coming out of the upstairs vents. Would this have anything to do with it? Also in a general damper question since it is new to me - I would assume it would be ideal to open it completely in the summer and close it a bit in the winter since hot air rises.
Thanks for any help!
airman.1994
08-05-09, 07:24 AM
you might have found the problem. Also it could be that the duct is not sealed. Damper potions should be correct.
millercv
08-05-09, 07:26 AM
you might have found the problem. Also it could be that the duct is not sealed. Damper potions should be correct.
Thanks for the reply!
That is what I'm going to be checking next - I did realize this morning that on the second story that the back side of the duct is the back side of the closet in the bathroom - where we have been taking more showers than normal since our second bathroom is out of commission. Going to check to make sure that is well sealed next.
Thanks for the reply!
That is what I'm going to be checking next - I did realize this morning that on the second story that the back side of the duct is the back side of the closet in the bathroom - where we have been taking more showers than normal since our second bathroom is out of commission. Going to check to make sure that is well sealed next.