Blown PVC connection

[shadowman]

Tuesday I came home from work to strange noises from the pool and immediately noticed the water level was way down and the skimmer was sucking air. I opened the equipment shed and it was flooded and everything had been sprayed with pool water. I found that one of the PVC welds had failed and the main line from the filter had opened up. The previous owner or pool contractor had used a short length of strange pipe that appeared to have been flexible at one time. It was translucent and looked like it had coiled wire imbedded in the plastic. It also was clear that the original weld had never fused this pipe so it was waiting to blow all these years.

Has anyone heard of this kind of pipe being used? I am posting this more as a heads-up to others but I would like to know if this pipe is in common usage out there.

[Vinyl_Guy]

There is flexible PCV of both clear and opaque types. They do have a "wire" to give them strength and prevent them from collapsing at high suction rates, or being crushed when back-filled. The supposedly have the same rating and qualities of their rigid PVC counterparts (Schedule 30, 40 etc). But they do require some experience when plumbing with them, and are not good for certain situations.

Is the rest of the system "hard piped" with rigid PVC?

Sounds to me like that section might have originally been hard PVC, when it failed the areas between where the repair was needed was too short to put in rigid PVC. So the person opted for flexible rather then make more extensive changes.

The problem with doing this with flexible PVC is, it comes in rolls. With a short piece , it always has an arc or bend to it. It's almost impossible to straighten them in short lengths. The point at which this flexible PVC met up with the glued socket was probably never square and seated in the glue properly.

Even when you plumb with flexible PCV in long lengths, you should arrange and feed it into a glue socket so that it's coming in as straight as possible. Even holding it straight while the glue sets up then letting go, can create a stress that eventually make the bonds fail.

Many builders/serviceman still resist using this product to this day.

[shadowman]

Thanks for the info Vinyl Guy. I have done a lot of PVC work in my day but I had never seen this before. That section of pipe had been cut and spliced so many times, it was one plugged tee or coupling after another. I cut out the whole section and replaced it along with the check-valve that was in the middle. My system is 30 years old so I guess it was due for a refurb job.

[Vinyl_Guy]

Thanks for the info Vinyl Guy. I have done a lot of PVC work in my day but I had never seen this before. That section of pipe had been cut and spliced so many times, it was one plugged tee or coupling after another. I cut out the whole section and replaced it along with the check-valve that was in the middle. My system is 30 years old so I guess it was due for a refurb job.

Wow 30 years. I've seen a few that old, but not many. You had to do this one because you needed to get the system up and running. But doing the rehab is the way to go, chop it all out and go all new. Then you can plan your attack and plumb it the best way possible. You might even want to move a few things around for better access or easier plumbing.

I didn't do any above ground plumbing with flexible PVC. First off it doesn't do well with people turning valves and pumps going on and off. Doing the "system" plumbing in all hardpipe gives it that solidity it needs. I used to covert over under ground when coming up vertically as deep as possible to give the system plumbing a "stiffness". That's if I was using flexible underground. It also sags with heat if it's used horizontally out bound of a heater, putting stress on the socket welds. System and above ground plumbing is just not the correct application for flexible pipe.

I did use it for underground though. Easy to roll out around the pool in great lengths, makes for less fittings to turn corners. Less fittings means less chance of a weld failures. It also has a little "give" to it, so if a pool isn't winterized correctly and water freezes the full inside diameter of the pipe, there's less chance of breakage. Rigid PVC often shatters at that point, making the line virtually useless for all intents and purposes.

But it's expensive, and was a wash in costs versus labor, but quicker. And the same money but faster is usually better. Time is money in any business. There are builders who refuse to use it. And actually when it first came out it was attacked by a termite or some type of insect, I forget exactly. It can be chewed through by a aggressive insect or "mole" type animal. There were some lawsuits and stuff going around, but that was some 15+ years ago.

Wheh, was it that long ago? .

[shadowman]

In that 30 years I'm sure various pieces have been replaced. In the 4 years I've been here, I've replaced 2 sections of pipe, the booster pump, and both timer switches. The rusty, derelict heater is original but I have never used it since I have solar. Some day when I get ambitious, I'll throw out the heater and replumb everything. Probably when the heater starts leaking