Old A/C attic unit in Fla. - water leak!
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Old A/C attic unit in Fla. - water leak!
Good evening. It appears that I have a crisis, but I'm wondering if I can wait a little while for entire replacement if I do a little DIY fix-up for now. Home A/C units are completely foreign to me at this point.
I'm in Florida, and it's hot and humid now. I have an ancient unit in my attic that has 2 drippy water leaks on one end. I don't even know what that area of the unit is... the condenser? It is encased in sheets of OwensCorning fiberglass/foam, and large ducts come out of that area on both sides.
In one of the pictures below, I drew little red circles around the drip areas. The water is leaking and dripping through 2 spots on the underside of the fiberglass/foam, at the outer edges.
Does anyone here know why it might be leaking? And if so, might I be able to epoxy or something over the 2 leak areas? I don't actually have epoxy, but I have rubberized, waterproofing roofing tar. It seals even on wet surfaces. Might that work, as well?
Or, if I patch the leak areas, am I suddenly trapping water inside the unit that needs to get out? Would I be causing a pressure buildup?
***I have put the pictures in the order of:
-- views of the manufacturer's label
-- another view of the mfr's label
-- left/one end of the unit
-- center of the unit
-- right/other end of the unit (w/the leaks)
-- very end of the right side (w/leaks circled)
Thank you immensely for any help!
~Mike


I'm in Florida, and it's hot and humid now. I have an ancient unit in my attic that has 2 drippy water leaks on one end. I don't even know what that area of the unit is... the condenser? It is encased in sheets of OwensCorning fiberglass/foam, and large ducts come out of that area on both sides.
In one of the pictures below, I drew little red circles around the drip areas. The water is leaking and dripping through 2 spots on the underside of the fiberglass/foam, at the outer edges.
Does anyone here know why it might be leaking? And if so, might I be able to epoxy or something over the 2 leak areas? I don't actually have epoxy, but I have rubberized, waterproofing roofing tar. It seals even on wet surfaces. Might that work, as well?
Or, if I patch the leak areas, am I suddenly trapping water inside the unit that needs to get out? Would I be causing a pressure buildup?
***I have put the pictures in the order of:
-- views of the manufacturer's label
-- another view of the mfr's label
-- left/one end of the unit
-- center of the unit
-- right/other end of the unit (w/the leaks)
-- very end of the right side (w/leaks circled)
Thank you immensely for any help!
~Mike






Last edited by whatwouldmikedo; 07-07-12 at 08:32 PM. Reason: forgot to subscribe to thread
#2
Would like to see a full unit picture if possible. but from what I can see now, there is a good possibility that drain pipe (white PVC pipe) is clogged. Does that white PVC pipe have an opening ? if not you need creat one (reverse T opening), a P-trap build-in there even better. Anyway, you need to check that pipe to see if it is clogged (cut it open, if the pipe does not have an opening). ANd also find out where is that pipe lead to, if you can find the other end, then you can check to see if there is water come out there.
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Thank you much. That's a start. I don't know where the PVC pipe drains to. I will try to figure that out in the morning, and I will try to check for clogging.
I'm sorry, but that's the best picture-taking that I can do in my attic. I wish that I could snap from farther away. In my bottom 4 pictures, the first 3 would make a left-to-right panoramic view of one side of the unit. And the 4th picture is a view of end of the right side, as if to say it's the head or the tail, so to speak. Can you tell what that end/area is? And why would water choose to leak from there? ...Thank you again!
I'm sorry, but that's the best picture-taking that I can do in my attic. I wish that I could snap from farther away. In my bottom 4 pictures, the first 3 would make a left-to-right panoramic view of one side of the unit. And the 4th picture is a view of end of the right side, as if to say it's the head or the tail, so to speak. Can you tell what that end/area is? And why would water choose to leak from there? ...Thank you again!
#4
Hard to tell which end is head or tail unless we know where the blower is and which way it blows., but it does not matter, all we need to see is more of that pVC pipe area and to see if there is a drain pan or secondary drain pipe under the whole plenum. Is the leak area the lowest point of the plenum ??
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There is an approximately 3' x 4' drain pan under the center part of the unit. Some water drains into it and down into a narrower pipe that connects on the side opposite of the pictures -- the side opposite that of the visible PVC pipe.
As for orientation in the pictures, the first of the 4 pictures of the unit (after the 2 label pictures) shows the intake box (large silver square) that comes up from the intake vent of the ceiling. That is at one end of the unit.
The area with the leak is on the opposite end of the unit. I don't know if the leaking end is lower than the rest of the unit. It all seems to hang level, but I could be wrong. But the drain pain does not extend to under that end area.
As for orientation in the pictures, the first of the 4 pictures of the unit (after the 2 label pictures) shows the intake box (large silver square) that comes up from the intake vent of the ceiling. That is at one end of the unit.
The area with the leak is on the opposite end of the unit. I don't know if the leaking end is lower than the rest of the unit. It all seems to hang level, but I could be wrong. But the drain pain does not extend to under that end area.
#6
I see the picture now. If you have water in the drain pan, indicates the primary pipe (That white PVC) is clogged. The drain pan usually only catch the coil (middle) part of the plenum, and secondary drain pipe will drain all the water to the pan if the primary is clogged. water should not be leaking in any other area. so this may indicate even the secondary pipe has some problem. If everything is normal, you should not see water anywhere. For the primary pipe, You need to cut it open (if you don't have an existing opening)
and figure out a way to clean it, depends on where the clogging is, it may be easy or hard to do. Professional techs use air compresser most time to blow it out, but you can try wires, vacuum, etc.. if nothing work, you will have to call a pro for help. You still have to find out why the secondary pipe did not drain all water into the pan. no water should leak through the plenum,
and figure out a way to clean it, depends on where the clogging is, it may be easy or hard to do. Professional techs use air compresser most time to blow it out, but you can try wires, vacuum, etc.. if nothing work, you will have to call a pro for help. You still have to find out why the secondary pipe did not drain all water into the pan. no water should leak through the plenum,
#7
Good advice on checking the drain line above. If there is no opening to check the drain line then cut out the 90 and install a T instead. Try to blow through the line with a shop vac if possible. If that is the problem and it clears then put a little bleach through the line on a regular basis in the future to help prevent any future blockage. I would venture to say that the drain line will go outside right where the a/c lines exit and go to the cond. unit. Good luck.
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Thank you, folks. I checked the apparent pipe from the outside into which the a/c drain pipes empty. There was no buildup in there. I have a shop-vac, but that might be futile, as my bathroom and kitchen drainage meets into the same pipe that runs outside, and the suction would be reduced, I assume.
In the attic just now, I've just noticed that there's a small leak even where the secondary drain pipe connects to the unit. There's no way to get into that pipe without cutting it, and I don't trust myself to do all of that on something so crucial. I'll try to have a friend get up there soon to cut it, blow it out (I have an air compressor) and reconnect it all with a T.
Let me see if I have this right... Cut out the 90-degree corner that runs downward, blow it out, and then replace the corner with a T. And I assume that the T would be placed in with the "letter" tilted 90 degrees itself, and to cap the top so that it can be uncapped periodically to pour in some bleach. If I'm assuming correctly, the T should be installed like in this picture, right? (Again, thank you very much! I'll probably check into what I'll have to go through to get a whole new unit in not too long, either way, but I have to have a/c right now for a couple of reasons.)
In the attic just now, I've just noticed that there's a small leak even where the secondary drain pipe connects to the unit. There's no way to get into that pipe without cutting it, and I don't trust myself to do all of that on something so crucial. I'll try to have a friend get up there soon to cut it, blow it out (I have an air compressor) and reconnect it all with a T.
Let me see if I have this right... Cut out the 90-degree corner that runs downward, blow it out, and then replace the corner with a T. And I assume that the T would be placed in with the "letter" tilted 90 degrees itself, and to cap the top so that it can be uncapped periodically to pour in some bleach. If I'm assuming correctly, the T should be installed like in this picture, right? (Again, thank you very much! I'll probably check into what I'll have to go through to get a whole new unit in not too long, either way, but I have to have a/c right now for a couple of reasons.)

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I may -- may -- have unclogged the primary drain pipe, though I was completely wrong at first about which pipe was the exit on the outside. I shop-vac'd the correct pipe on the outside, and some murky water came out for a bit, then it turned clear.
But now I've discovered a drip coming down from where the pipe comes down out of the overhanging soffit on the outside of the house. As luck would have it, it's dripping right onto one of my external breaker boxes. But I've covered the top of that box with plastic for now.
My handiest friend is coming over now to check out the PVC pipe in the attic for potential replacement with a T, like you folks advised. I absolutely thank you!
As I said, I'd like to replace the whole ancient unit at some point, but I don't want to be rushed into choosing a company in an emergency, and overspending and whatnot.
~Mike
But now I've discovered a drip coming down from where the pipe comes down out of the overhanging soffit on the outside of the house. As luck would have it, it's dripping right onto one of my external breaker boxes. But I've covered the top of that box with plastic for now.
My handiest friend is coming over now to check out the PVC pipe in the attic for potential replacement with a T, like you folks advised. I absolutely thank you!
As I said, I'd like to replace the whole ancient unit at some point, but I don't want to be rushed into choosing a company in an emergency, and overspending and whatnot.
~Mike