Doughboy Liner Damaged by Chlorine?

[PoolDoc]

Running with un-controlled chlorine levels (no testing) can DEFINITELY get you in trouble. Sounds like you may have ID'd the problem.

@Carl: I called Hoffinger, and talked to several people there. Apparently, they even do their own molding for the plastics in the pumps and filters. They do buy the resins and raw PVC, but in rail cars. At that level of ops, I would assume they do QC analysis on the incoming raw materials.

[CarlD]

Thank, Ben.
Still seems iffy to me, however, that the liner should fail under those conditions.

[rajung]

As far as the filter goes,I always vacuum out all lines of water including the heater.
I removed the sand filter drain plug on the lower side and left it off.
Last year,I removed plug,let it drain a day then moved it to one of my insulated garages,though I didn't keep it heated,so I have to guess any water at the lowest part of drain remained in there other than what may have evaporated out.I never did tip over to drain more out the top since I left the multi selection valve attached.
Still wondering though, after all I have done,this shouldn't of happened this quick if at the extend it did.

[CarlD]

I don't know, but it sounds like freeze damage--at a guess.

[rajung]

I do tend to agree as far as freezing may be the cause since it split at its weakest point,the seam.
But I did do what the manual said as far as winterizing.Just a little confused,if I drained it and left the cap off all fall and winter there would be maybe 2 inches of water below the drain,when that freezes,wouldn't there be plenty of room for expansion?
Maybe I will leave outdoors again this year and do what you have been doing.
Moving to indoors in garage with a 2 wheel cart my have been a little to much force on the bottom side of sand filled tank at 150lbs putting pressure on the very bottom bolt that holds inner parts in place, that bolt is also right in line with the seam.
Thanks again for the info.

[CarlD]

Of course, any water you can get out of the tank is water that cannot cause freeze damage. Moving the tank, full of sand, especially if it was cold out (cold stiffens plastic) could also have weakened the tank.

But I'm just guessing.