- May 23, 2015
- 25,716
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Pool Painting
- Thread starter JPMorgan
- Start date
Water is seeping into the main drain area and into the pool from the hydro-static valve.... as expected. However, there is always a little bit of water sitting in that little "cup" in front of the line that runs from the main drain to the skimmer. If I vacuum it out it fills up again right away, but it never keep flowing... just sits in that little cup at the bottom of the main drain (at 5 o'clock in the picture below). If it helps, I can take a video and send it tomorrow. I think it is more than condensation because the water flows into that little cup immediately after I vacuum it out. I was able to pump water out of the pool using the main drain, so it was drawing water from the bottom of the pool through that line.
Mystery solved! I finally went and looked in the skimmer and saw there was a little water in there that was filling up from the skimmer line. I sealed off the skimmer line, vacuumed the water in the skimmer and no longer have water filling up the bottom of the main drain. It's completely dry now.
Nope! I was wrong. I still see water sitting in that little cup at the bottom of the main drain. Can't understand where it is coming from. Skimmer line is sealed off. Seems like that main drain line to the skimmer should be dry, but it has water in it. I can vacuum all day long and there is still water in that line running from the main drain to the skimmer. It doesn't run out into the pool... just about an inch always sitting at the bottom in that little cup in the main drain no matter how much I vacuum. If I look down into the line from the skimmer I can also see water. A real head scratcher!
Any chance it’s morning condensation ? Especially being all slick with the fresh paint any drops would probably find their way there.
- May 23, 2015
- 25,716
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Sounds to me like your MD line between the drain and the skimmer may have a tiny leak. If you can rent a bore scope you can try to find it but otherwise you may need a leak professional to come out to find it. Some drain repair plumbers can to do pipe fixes in place but typically in old pools when the MD has a leak, the drain simply gets sealed off and you lose it. Bummer.
No.... even later in the day when the pool is dry there is water there constantly.
Yes.... I was told that if that line gets damaged the only economical thing to do would be to seal it off. I am posting another video. This one is from inside the skimmer. It looks to me like there is water sitting in the MD line, even though I have the vacuum running from the other side of the MD line while I am taking this video. Even if there is some kind of leak, I wouldn't expect to see water sitting in that line. Seems very odd. Also..... I was able to pump water out of the pool using the main drain when I was emptying the pool. Wouldn't that be hard to do if there was a break in that line. I know last summer I was able to draw water from the bottom of the pool, so at least it wasn't damaged to the point of being completely non-functional.
- May 23, 2015
- 25,716
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Perhaps the MD line is clogged and there's water backed up in there that is just slowly dribbling out?? Hard to believe that water would come up to the level of the skimmer but not flow out the MD.
Know anyone with a borescope that can look in the pipe? They sell cheap ones on Amazon but it's lousy to pay for something you may only use once. Much easier to diagnose the line while the pool is drained.
By the way, make sure you pop that hydrostatic valve open ... you don't want to accidentally float the pool.
Know anyone with a borescope that can look in the pipe? They sell cheap ones on Amazon but it's lousy to pay for something you may only use once. Much easier to diagnose the line while the pool is drained.
By the way, make sure you pop that hydrostatic valve open ... you don't want to accidentally float the pool.
I have been popping open the hydrostatic valve periodically and vacuuming up the water that comes out (in order to keep the bottom of the pool dry), but it is spring loaded, i.e., it lets water seep into the pool when pressure builds up. If I haven't opened it for an hour I start to see water seeping out of the valve, then I open it and vacuum. Isn't that spring-loaded mechanism the safeguard against possibly floating the pool... or causing any other damage?
Question: If I took an electrical fish line and ran it down that main drain line from the skimmer, shouldn't it come out at the MD? Would't that tell me that there's no blockage if it goes through? I had a leak detection service out last year and they charge $425 for per call.
If the fish line is not a good idea, there is a plumber I know pretty well. Maybe I'll call him to ask if he has a borescope.... but if a borescope goes through the line, wouldn't a fish line also go through?Maindrains are usually run in flex PVC so they can actually be scoped with a smaller unit. A fish tape could make it thru, so can a smaller 25ft plumbers snake
- May 23, 2015
- 25,716
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
I was thinking the borescope would be to look for leaks not to snake the line.
I might try the fish tape to check for any blockage.... or shoot some water from the hose down that line and see what happens at the MD. If it has a leak, it's not going to be repairable any way, right? I do believe when I had the leak detection done last year, the MD line was checked and was okay. However, I suppose it's possible that something has happened since then.
Waiting to get my hands on a plumbers snake. In the meantime I took an old piece of extension cord and tried to fish it through the MD line. From above, it only goes in about a foot and I can't get it to go further. Either there is a turn I can't push it through or there is some blockage. Then I tried from the main drain and it goes in about 9' an then I hit resistance. Next I plugged the MD line and filled the skimmer with about 2 gallons of water, ran the vacuum at the MD (so the water wouldn't equalize as it drained), then pulled the plug. The water drained pretty quickly (see video). Any further thoughts?
Update: Got a hold of a plumbers snake. Worked from the skimmer and got it past the first area of resistance that I felt before (must be a turn in the pipe). Hit one or two more areas of resistance. Got past one, but eventually got hung up again. Decided to hit the line with my power washer, then put my shop vac on blower and stuck it in the skimmer. Then, went down to the MD and stuck the vacuum in there again. End result.... both the little "cup" in the bottom of the MD and the line coming into the skimmer are now completely dry and it seems like the air going through the line is pretty strong. My sense is that there is no obstruction in the line, but.... let me know what you all think.
I've posted two videos below. Not sure why I have been seeing standing water in that "cup" in the MD and also in the skimmer, but it is now dry on both ends. The only thing I can think of is that there are some turns in the line that made it difficult to completely clear out the water (like a p-trap). It is a very old pool.... who knows how they were building things back then.
I've posted two videos below. Not sure why I have been seeing standing water in that "cup" in the MD and also in the skimmer, but it is now dry on both ends. The only thing I can think of is that there are some turns in the line that made it difficult to completely clear out the water (like a p-trap). It is a very old pool.... who knows how they were building things back then.
Last edited:
- May 23, 2015
- 25,716
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
A P-trap Is possible but your skimmer is what, 6ft above the MD, or more ?? That would be one awfully big P trap.
Leave it open and monitor it for a day or two. See what happens.
Leave it open and monitor it for a day or two. See what happens.
Was planning to start filling the pool this evening. What should I specifically be looking for until then? Right now the line coming into the skimmer and the "cup" at the bottom of the MD both remain bone dry. I am taking a last look around before I start filling the pool. I put the pool light back in, but snapped the picture below before doing so. Does this look problematic at all? I think the pool company took care of a leak in the light fixture a couple years ago. I see that "putty" (shown in photo below) all around the inside edge of the pool light housing. Looks like a pretty good seal all the way around. Should I add some where the wire goes into the pool wall.... or does it look okay.... and what the heck is that stuff and where do I get it (if needed)?
I'm pretty sure I read that a garden hose is the cheapest (but slowest) way to fill a pool. I'm not in a hurry so I'll take cheapest way unless anyone has another suggestion.
Thanks to everyone for all the help on this project. Finally nearing the end! Really appreciate all the help.
TFP!I'll send final photos when the pool is full...
