Could this be the cause of dripping on my ceiling?

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Old 08-18-20, 12:27 PM
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Could this be the cause of dripping on my ceiling?

I have noticed that my drop ceiling tile have dried stain on it. I doubt there are water leaking from the PVC pipe above the duct. Could this duct (I believed it carries cold air from the air condition) causes the issue I'm seeing by condensing humid air and leaked out of the duck tape there?

 
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Old 08-18-20, 12:43 PM
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Yes ducts will sweat when the conditions are right for it. You can see the drips and water stains on the edges, elbow and bottom of the ducts. Wrapping them with a duct insulation sleeve will help some. Also look for a source for the warm humid air that is causing it to sweat. If this is in a warm unconditioned room like the mechanical room, that is part of the problem. Cool conditioned air would not be as likely to cause condensation on the ductwork.
 
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Old 08-18-20, 05:11 PM
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I always insulate supply ducts with at least R4 within the "Building Envelope" to eliminate sweating when some bozo sets the thermostat at 68 "to cool down faster" and then forgets to raise the setting to the 75F normal. Codes require R8 in Attics and R6 in other unconditioned spaces, such as unconditioned Mechanical Room.

And what's with the cloth duct tape??? That stuff's prohibited for use on ducts, which require a tape marked "Ul181..." - always a foil tape in my experience. Yes, I know it's called "Duct Tape", but just use it to hold your broken bumper on, or whatever.

Oh yes: Three screws are required to secure round duct joints, couldn't see any in the image.
 
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Old 08-18-20, 05:19 PM
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If it's a basement, and your getting that much condensation off the cold air ducts you really need to do something to reduce the humidity. That much moisture could cause mold to grow, a de humidifier run during the warm months will make a huge improvement!
 
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Old 08-19-20, 05:12 AM
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Thank you so much for all the suggestions, much appreciated! Yes, I was curious about the use of cloth duct tape? Should I take that out before using the foil duct tape? Is there any insulation that does not contain fiber glass? This is in the finish basement.
 
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Old 08-21-20, 02:41 AM
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Do not attempt to apply UL181 tape over the illegal cloth tape. Instead, first remove the cloth tape and any of its remaining residue from the duct.

We call the non-fibrous glass insulation "Bubble Wrap", one such product is manufactured by "Reflectix". Having done a DIY in my house reinsulating ducts with fibrous glass wrap, I became a devoted fan of Bubble Wrap, now spec it on all my jobs. Several contractors with whom I've worked prefer it too. Use R4 in "conditioned space", R8 in attics and R6 in other unconditioned spaces.
 
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Old 08-21-20, 04:23 AM
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Yes, I know it's called "Duct Tape"
Maybe it's me but we call it Duck Tape!
 
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Old 08-22-20, 10:23 PM
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As in duck when anyone tells you to use it on ducts?
 
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Old 08-22-20, 10:26 PM
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Duck tape is a brand name of duct tape.
 
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Old 08-31-20, 02:21 PM
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I had the same issue in my basement. Replacing the air handler fixed the problem. The old unit was 30 years old and the evap coil was all gummed up and damaged, so it couldn't adequately remove humidity. Make sure your coil is clean and filter is changed often. You may also be able to slow the fan speed down which will allow the unit to remove more humidity.
 
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Old 09-05-20, 01:47 AM
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Do make sure the unit is delivering more than mfgr. minimum (usually 320 or 350 CFM/Ton) before slowing the fan, and good luck finding a contractor who knows how to do that!

As always, there are a bunch of highly skilled contractors out there, may their tribe increase.
 
 

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