Thread: What are all these weird things in my Air Duct?

I unscrewed an air-conditioning vent and this is what I found. Questions now:

1. What kind of air duct is this?

2. What is the black stuff?

3. What is the white stuff?

4. What is the red stuff on the right side of the second photo that is closest to my ceiling?

5. What is the red stuff in the top right of the first photo that is farthest from the ceiling?

.... Thanks for any help understanding what I got going on here. I have previously only seen metal air ducts.



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Originally Posted by floridaguy

I unscrewed an air-conditioning vent and this is what I found. Questions now:

1. What kind of air duct is this?

2. What is the black stuff?

3. What is the white stuff?

4. What is the red stuff on the right side of the second photo that is closest to my ceiling?

5. What is the red stuff in the top right of the first photo that is farthest from the ceiling?

.

1. Insulated metal.

2. Insulation

3. Paint over spray

4 & 5. Can't help you there.
.... Thanks for any help understanding what I got going on here. I have previously only seen metal air ducts.

It's a fiberboard duct, with dirt, mold, paint/texture over-spray.

Hard to say from here what the red stuff is, it could be the fiberglass from the ductboard. Some of them are yellow, some are orange, some are pink.

Dom.

Should it be replaced because of the mold?

Originally Posted by floridaguy

Should it be replaced because of the mold?

Have it tested for mold, there are also companies that clean ducts(I dont know if they can do fiber ducts or not, but they will have an idea of what to do), check refences and get at least two estimates. I think the red stuff may be a spray on type sealant or paint. Let us know what you find out. I have seen many fiber ducts and dust collects on the inside, similiar to a filter. I dont like them, even though they are quieter and better insulated, but thats my opinion. Now if they would line the inside I think they would be a much better product. Just my pennies

Originally Posted by MARVIN TOWNSEN

Have it tested for mold, there are also companies that clean ducts(I dont know if they can do fiber ducts or not, but they will have an idea of what to do), check refences and get at least two estimates. I think the red stuff may be a spray on type sealant or paint. Let us know what you find out. I have seen many fiber ducts and dust collects on the inside, similiar to a filter. I dont like them, even though they are quieter and better insulated, but thats my opinion. Now if they would line the inside I think they would be a much better product. Just my pennies

From what I have read testing for mold is not necessary. You just want to get rid of visible mold and you want to make sure that you prevent moisture which causes the mold in the first place. I don't think it's really possible to clean fiberboard/ductboard/whatever they call this... I am wondering how expensive it will be to just have this one piece replaced?

I should have clarified earlier that this vent was leaking/had moisture because it caused a small hole in the ceiling drywall by the vent.

Originally Posted by floridaguy

I should have clarified earlier that this vent was leaking/had moisture because it caused a small hole in the ceiling drywall by the vent.

Where did the moitsure come from? The only thing an estimate should cost you is time, It wouldnt hurt to have a proffessional cleaning service look at it.

I would pull the grills off the rest of the registers and look at the condition.

You can always re-duct the house, cost about $200 per drop for new flex duct here in Central Florida, plus a new trunk. It gets pricey real fast.

Dom.

Originally Posted by Dom D'Agostino

I would pull the grills off the rest of the registers and look at the condition.

You can always re-duct the house, cost about $200 per drop for new flex duct here in Central Florida, plus a new trunk. It gets pricey real fast.

Dom.

the others look OK. just this one looks moldy.

Duct liner, the red stuff is duct liner glue, popcorn ceiling paint and some dust of unknown origin.

Originally Posted by David Bell

Duct liner, the red stuff is duct liner glue, popcorn ceiling paint and some dust of unknown origin.

That's what I was thinking as well. Sure doesn't look like any ductboard I've worked with. Looks like metal duct at the bottom is not insulated, could be cause of condensate at the ceiling.

The duct liner stops so as not to interfere with the damper on the register.

Originally Posted by David Bell

The duct liner stops so as not to interfere with the damper on the register.

I understand that. If it is not insulated on the other side of the metal, in the attic, it will sweat.

Really have not seen registers connected straight to the duct before, always seen register boots. This way seams to be very labor expensive.

Those are more than likely to be returns, the liner also acts as a sound barrier to fan noise, the uninsulated ends are normally below the attic insulation also.

Would this paint overspray in the return air duct be a comment on your report?

rick

Unfortunately most builders and most painting contractors don't see a need to cover outlets. Obviously it should be done.

Originally Posted by David Bell

Duct liner, the red stuff is duct liner glue, popcorn ceiling paint and some dust of unknown origin.

Agree 100% That is metal duct not fiber duct.

Paint over-spray is only a problem if you don't like to be able to look into the register/grille and see it. Many good HVAC engineers and contractors (and even some of the not-so-good ones ) like the interior to be painted flat black for aesthetics.

testing will be a waste of money. There is mold in the air everywhere and an air duct will have some mold spores - not growing but spores. So that will show up in a test. If it was wet and there is clear evidence of growth then it should be replaced or encapsulated.

The liner can be cleaned if it is not in poor condition. There are approved paints for use in the ducts that are antimicobial and will encapsulate any contaminates.

The ducts can also be fogged with Sporicidin. Another thing to consider is adding a UVC light above the A coil.

Originally Posted by David Bell

Duct liner, the red stuff is duct liner glue, popcorn ceiling paint and some dust of unknown origin.

I agree