TFP Method + Autocover + SWCG + Failed Pump = Liner Wrinkles

[Seagar]

1st full year with a vinyl liner pool and swcg.
Did the whole bioguard mineral springs system for the end of last season and had an algae bloom so wanted to avoid that this season and adopted the methods on this forum.
Water has been great, but had an issue with the pump stopping a few weeks back. With the autocover closed the water temp at the surface got hot. Shortly after I noticed some wrinkles in the liner.
Getting a new liner for other reasons but rsconsidering TFP Method because PB says the wrinkles are from the high chlorine (maybe made worse by heat).

My CYA is 80 and FC 8. PB was astonished at the FC 8 level.

Any thoughts on the chemistry and heat and liner wrinkles?

Thx!

 

[mknauss]

Liner wrinkles typically from low pH.

 

[wireform]

That's all bull feathers with the liner. The liner slipped and that has to do with either the water level was brought down too low for some reason. Or not installed correctly and the pb is finding blame elsewhere if you buy into it.

 

[Homebrewale]

I'm sure the PB was astonished since he likely follows the FC should be between 1 to 3 ppm recommendations that are outdated. When I recently visited my PB to pick up some sand, I brought a water sample just for fun to see their recommendations. They were astonished with my FC of 7.5 and was recommending a magic potion to reduce it right away.

 

[Jimrahbe]

S,

Since you have an autocover, there is no reason for your CYA to be at 80... Although none of your pool builder claims are true, you could lower your CYA and corresponding FC target if you wanted.

What kind of pump did you have that went bad??

Thanks,

Jim R.

 

[Newdude]

They were astonished with my FC of 7.5 and was recommending a magic potion to reduce it right away.

And here I'd tell you to add 2.5 more.

 

[Seagar]

pH has been a struggle to keep high (>7.5), but it’s never dropped below 7.2 and is usually around 7.5. Have a stash of 20 Mule in the cabinet.

Pump is a Pentair intelliflow VSF. Apparently there’s a firmware issue with the ones made during Covid and they need updated by Pentair. The rep came by and updated it and it’s been working fine. That was a fun rabbit hole digging into the comm bus for the intellicenter wondering why it lost communication with the pump.

PB reached out to bioguard who said they’d never heard of running higher levels of FC and CYA. Not surprised.

Like I said pool was looking great and no liner wrinkles until the pump stopped. One time was the fourth weekend when we were away and the air temp got pretty hot. I imagine the water temp at the surface under the cover was +100.

My gut says the heat caused the wrinkles. I’m unclear if the high FC contributed under those conditions.

PB said with the autocover they would keep CYA under 30. Maybe I’ll switch to that and just keep FC at 3. So many variables with pool material, chlorine source, time covered, geographic location, etc. that it’s hard to know if what you read is right for your specific situation.

In the end, I’m still dealing with getting things right from the build and I don’t want PB or any manufacturer to be able to use bad chemistry as an excuse for other problems. So I’ll prob have to stay closer to industry standards.

 

[Newdude]

So many variables with pool material, chlorine source, time covered, geographic location, etc. that it’s hard to know if what you read is right for your specific situation.

Here. We've been at it 17 years with this many members.



We've seen your situation, in your climate, *thousands* of times. The advice has all been fine tuned for you, your pool type, your fill water and your weather. The collective wisdom here if off the charts, if you're wise enough to recognize it.

 

[Seagar]

Fair point and I’ve learned a ton here and appreciate the collective wisdom!

I guess back to my question on what caused the wrinkles:
- I don’t think it was an install issue b/c it’s been in for a year without issues (at least not wrinkles).
- Is pH of 7.2-7.5 low enough to cause wrinkles (I wouldn’t think so)?
- Has anyone seen heat build up under a cover cause wrinkles?
- I know my 80/8 (CYA/FC) levels are inline with TFP Method. Has anyone seen any issue with these levels under high temperatures?

Thx!

 

[Newdude]

I don’t think it was an install issue b/c it’s been in for a year without issues (at least not wrinkles)

Me either.

Is pH of 7.2-7.5 low enough to cause wrinkles (I wouldn’t think so)?

No it needs to be looooow. Like 5 low. 7.2 is in range. If it's PH wrinkles there are 7 million lines all over like a fingerprint. If it's long straight-ish wrinkles, that's a water behind/under the liner issue. Which do you have ? Got pics ?

Has anyone seen heat build up under a cover cause wrinkles?

Not that I've come across and we have tons of members with autocovers.

I know my 80/8 (CYA/FC) levels are inline with TFP Method. Has anyone seen any issue with these levels under high temperatures?

Not that I've come across.

I don't think temperature has anything to do with it. Your PB is grasping at straws.

Why is the liner being replaced unrelated to this ?

 

[Seagar]

Me either.

No it needs to be looooow. Like 5 low. 7.2 is in range. If it's PH wrinkles there are 7 million lines all over like a fingerprint. If it's long straight-ish wrinkles, that's a water behind/under the liner issue. Which do you have ? Got pics ?

Not that I've come across and we have tons of members with autocovers.

Not that I've come across.

I don't think temperature has anything to do with it. Your PB is grasping at straws.

Why is the liner being replaced unrelated to this ?

Pics of the wrinkles attached. It’s a few isolated areas - not all over.

There was a hole in the liner originally (bad seam in bench corner). A patch took care of it, but then we had other leaks and the PB thought it would be more seam issues so requested a new liner. Side note, the other leaks were not the liner - leak in a return line and leak at a skimmer faceplate.

But now we have a new liner sitting there and figure we should drop it in this season in order to:
- cover up the leaking return that now has an ugly white plug in it (if our last attempt to find/fix it fails)
- smooth out some minor divets in the vermiculite bottom
- use the new liner before it hardens or creases

I welcome any feedback on the wrinkle pics. There are prob 5 total areas with wrinkles like this (44’x22’ with depth 3.5’-9’). PB’s reaction to the pics and asking if it was chemistry related was “absolutely, that liner is cooked”.

 

[wireform]

I wonder if there isn't any water seepage coming from the deck in that spot. Being the deck gets hot and the water may be pretty warm perhaps the liner stretched. You can't grow a liner in one specific spot but maybe the water not being able to pass the water line got trapped there

 

[Newdude]

Pic #1 is well below the water line, so for that one the PBs thought process is that 2ft of water got too hot because the cover was on, in Ohio mind you. We have oodles of autocovers in hot climates without issue.

The pump being out of service is unrelated. If you could easily raise your temperature by turning the pump off, nobody would need heaters.

It's a water drainage issue IMO.

 

[Mdragger88]

Did it rain before this happened/was noticed? Do you have well points/sump around your pool?
That really looks like its from water behind there.

Fun fact- I have tons of wrinkles (my liner was left way too loose by the installers & has issues)
Anywhoo- I recently discovered a hole (from a bb ) in one of the areas with big wrinkles. It was noticeably loose there (more than normal).
I immediately patched the tiny hole & the liner in that area low & behold the liner is tight up against the wall again now. The wrinkle is still there though.

 

[Seagar]

To be clear I am the one guessing about the heat build up at the surface under the cover when the pump stopped, not the PB (he says 100% chemistry b/c of my crazy high FC…). One time when the pump was out and before I realized it, I opened up the pool - the kids jumped in - then the kids screamed that the water was burning them. A little dramatic, but I imagine it was a weird sensation with hot water at the surface. I felt the water and it was indeed hot (not scalding, but hot). So I wondered if the air pocket at the edges could have been a high enough temp to cause wrinkles. Or if that heat changed whether the high FC/CYA was safe for the liner.

That doesn’t explain the lower horizontal wrinkle though.

It’s been a wet summer here and when this happened we were getting regular downpours. However the drainage around the pool seems good. There’s a drain tile around the wall footers that route the water to a sump that empties to a storm drain. The deck and yard have good drainage away from the pool, too.

 

[Newdude]

(he says 100% chemistry b/c of my crazy high FC…)

Chlorine won't wrinkle a pool. It might bleach it white, but no wrinkles.

A little dramatic, but I imagine it was a weird sensation with hot water at the surface.

With my solar cover the top inch or so was similar at times. There were certain days it would steam when I pulled the cover like it was on the verge of boiling. I went up to 2 weeks at a time with no issue. Again, you have a normal situation going on and nothing magical happened under your cover that doesn't happen to anyone else with one.

Or if that heat changed whether the high FC/CYA was safe for the liner.

It did not.

That doesn’t explain the lower horizontal wrinkle though.

That's the smoking gun right there. The rest is a wild goose chase unless you believe you have 2 sets of wrinkles that showed up, at the same time, for different reasons.

 

[JamesW]

One time when the pump was out and before I realized it, I opened up the pool - the kids jumped in - then the kids screamed that the water was burning them.

I felt the water and it was indeed hot (not scalding, but hot).

How hot?

Maybe the heater is coming on without your knowledge and the water got really hot, like over 100 degrees hot, and that might cause the liner to get soft and expand.

Most likely the wrinkles are due to water getting behind the liner.

You can't really see ground water, so you would need to dig some holes to see how high it is getting.

The 8 FC did not make the wrinkles.

 

[JamesW]

Low pH (Like 4.5) can cause wrinkles, but very tiny and a crazy pattern.

Big wrinkles are usually due to an oversized liner and/or water behind the liner.

Heat can soften the liner, but it would need to get very hot everywhere, not just at the surface.

It might be a combination of excessive heat, water behind the liner and an oversized liner.