Ruptured filter cartridges

imported00

Member
Sep 23, 2020
8
Saint George, UT
First time posting but a regular reader. I searched the forums and I couldn't find any information that would help me with my issue. Sorry of this is a repeat.

I am having issues with blown filter cartridges in my Pentair DE Quad 100 Filters. The pool is new this spring and opened in May.

Pool Characteristics:

1) 50,000+ gallons

2) Two Pentair DE Quad 100 Filters (One filter is assigned to the 12 foot deep end. The other filter is assigned to the 3 skimmers)

3) Three Pentair 3HP Intelliflo VSP pump. Each filter has its own pump. The other pump feeds rock slide and waterfall.

4) Return line is 2" and the flow can be split between the 6 wall returns and/or 2 shelf bubblers. (Both filters join into the same return 2' return line.

5) Pentair Hybrid heater

6) SWC generator

7) Sun shelf with 2 bubblers

8) Waterslide and slide

9) Acid dispenser

History:

At the beginning of July we came home to the entire pool floor coated in DE powder. The filter was opened and it was found that all 8 filters had failed, rupturing through the blue rubber end cap. Spoke with my pool maintenance company and no reason was identified as the cause. New filters were placed and we moved on hoping it was a weird one time event. Recently larger white flakes started to appear on the pool floor at the return ports. Some return ports have heaver debris deposits than others. My pools service said it was "pool dandruff" coming from the SWC generator and recommended an additive to help control scaling. Today the filter was opened and we found that 5 of the 8 o filters had ruptured. This time the pool service thinks it may be the high-flow backwash valve causing the problem. I am at a loss as to the reason of continued filter cartridge failure. Any help would be appreciated.

Thanks
 

JamesW

TFP Expert
Mar 2, 2011
21,092
Probably plumbed wrong or wrong multiport.

Does the multiport say for triton and quad de or does it say for fns de?

There is a silver barcode sticker on the multiport on the front pipe. There is a P/N (part number) on the sticker. What is the number?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
20,358
Northern NJ
Welcome to TFP.

Interesting setup you have. Both filters join into the same return 2' return line caught my eye.

What speed do you run the pumps connected to the filters?

What are the PSI of the filters?

My WAG is both filters to the same return is creating back pressure into the filter.

Post pics of your equipment.
 

JamesW

TFP Expert
Mar 2, 2011
21,092
Return line is 2" and the flow can be split between the 6 wall returns and/or 2 shelf bubblers. (Both filters join into the same return 2' return line.
First of all, you don't need two pumps. The Intelliflo is more than enough for your pool.

Second, putting them both on the same return is a bad idea. For one thing, if one pump is off and the other is on, you will get reverse flow through the off filter.

Is this a commercial pool?

Why two pumps?
 

JamesW

TFP Expert
Mar 2, 2011
21,092
If the cartridges are rupturing, it's almost always due to the water going from the inside of the cartridge to the outside instead of from the outside to the inside.

If your valve doesn't match the one in the picture, it's the wrong one.

People get confused because the quad de is a de filter, but it gets plumbed like a sand filter.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,437
Bedford, TX
00,

What JamesW suspects is that your filters are plumbed backwards, which we have seen several times on the Quad 100.. It has the input and outputs backwards from a normal filter. If the wrong MPV is installed then water goes into the center of the cartridges and blows them out...

Show us a pic of a damaged cartridge..

Thanks,

Jim R.
 

imported00

Member
Sep 23, 2020
8
Saint George, UT
Probably plumbed wrong or wrong multiport.

Does the multiport say for triton and quad de or does it say for fns de?

There is a silver barcode sticker on the multiport on the front pipe. There is a P/N (part number) on the sticker. What is the number?
2
The PN is 272120. Good catch! My multiport says for MSP, FNS and FNS plus filters only. Both of my DE filters are Pentair. The culprit is that wrong valve??? My pool service is also a pool contractor, though he didn't build mine. We checked to make sure it was plumbed correctly and it is. I is one of the first things we checked. After the initial blow out is was thought that perhaps during backwash the flow as being reversed so it was recommended that I also place back flow prevention valves before each filter. Now there is a back flow valve before each filter.
 

JamesW

TFP Expert
Mar 2, 2011
21,092
Note that part number 272120 is the part number for the label that goes to the multiport part number 261142, which is a DE multiport.

The silver sticker with the barcode and the manufacturing date probably has P/N 261142.

The silver sticker is usually on one of the vertical pvc pipes below the valve.

Even though you have a de filter, it gets the sand filter multiport because the quad de has the in/out reversed compared to the regular de filter.

I would remove one of the pumps as it's not needed and will only cause problems.

You should not even need to run the single pump at full speed to get good filtration.

You probably won't need anything more than about 2,750 rpm at the most.
 

imported00

Member
Sep 23, 2020
8
Saint George, UT
00,

What JamesW suspects is that your filters are plumbed backwards, which we have seen several times on the Quad 100.. It has the input and outputs backwards from a normal filter. If the wrong MPV is installed then water goes into the center of the cartridges and blows them out...

Show us a pic of a damaged cartridge..

Thanks,

Jim R.
I contracted the pool myself. The pool is located at my residence. Spent a lot of time on TFP to learn what I thought I needed. I suppose I should have asked questions and posted my designs first to get feedback before I took the plunge.

1) The PSI has always sat at about 15. my pol service said that its not normal but that all pools are different.
2) The wrong wrong port causing a reversed catastrophic water pressure makes sense. The outside of the DE ruptured cartridges are always clean and the inside tube of the cartridge is always caked in DE. See pictures.
**** I will be ordering the correct multiport today*****
3) My equipment is different. I am limited to 21/1 feet by 20. See pictures.
4) I chose to run two pump fort the filtering because I was worried that the skimmers would get enough suction. I think the worry was founded since I do not get nearly enough pull at the skimmers. It is not uncommon to watch debris float right past the skimmer intake. Though if placing two pumps into one two inch return will cause issues (possible underground pipe rupture) then a pump should be removed.
5) If you have some insight into increasing the water draw at my skimmers please let me know

Thank you everyone so much for the information and quick response!!!!!!!
 

Attachments

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
7,176
Central California
I love to see the TFP experts in action! Nice job you guys.

00, if you've got either or both of your main drains or vacuum running, those will suck the life right out of your skimmers. I solved for that by eliminating main drains and putting an actuator on my vac line. The only time the vac line is open is for vacuuming, with skimmer only partially open for safety. The rest of the time the skimmer gets all the action and works great. Before I did that, neither the skimmer nor the vac worked well, even at high RPMs.
 

imported00

Member
Sep 23, 2020
8
Saint George, UT
Note that part number 272120 is the part number for the label that goes to the multiport part number 261142, which is a DE multiport.

The silver sticker with the barcode and the manufacturing date probably has P/N 261142.

The silver sticker is usually on one of the vertical pvc pipes below the valve.

Even though you have a de filter, it gets the sand filter multiport because the quad de has the in/out reversed compared to the regular de filter.

I would remove one of the pumps as it's not needed and will only cause problems.

You should not even need to run the single pump at full speed to get good filtration.

You probably won't need anything more than about 2,750 rpm at the most.
James
the silver in the front pipe is PN
Note that part number 272120 is the part number for the label that goes to the multiport part number 261142, which is a DE multiport.

The silver sticker with the barcode and the manufacturing date probably has P/N 261142.

The silver sticker is usually on one of the vertical pvc pipes below the valve.

Even though you have a de filter, it gets the sand filter multiport because the quad de has the in/out reversed compared to the regular de filter.

I would remove one of the pumps as it's not needed and will only cause problems.

You should not even need to run the single pump at full speed to get good filtration.

You probably won't need anything more than about 2,750 rpm at the most.
James
The silver sticker on the most forward pipe is 261142. Is this the correct multiport?
Thanks!!
 

imported00

Member
Sep 23, 2020
8
Saint George, UT
I love to see the TFP experts in action! Nice job you guys.

00, if you've got either or both of your main drains or vacuum running, those will suck the life right out of your skimmers. I solved for that by eliminating main drains and putting an actuator on my vac line. The only time the vac line is open is for vacuuming, with skimmer only partially open for safety. The rest of the time the skimmer gets all the action and works great. Before I did that, neither the skimmer nor the vac worked well, even at high RPMs.
DirK
The main drain has its own pump and filter and the skimmers has its own pump and filter. I think that with all the DE goin into the cartridges central tube the flow has been severely restricted. TI never understood why i wasn't see DE on the outside of the filters?????!!!!!! TFP experts are correct the filters plumbing is all wrong.
Thanks again!!!!!!
 

JamesW

TFP Expert
Mar 2, 2011
21,092
The silver sticker on the most forward pipe is 261142. Is this the correct multiport?
No, that's definitely the wrong one.

There's a lot going on there. It's hard to tell exactly what goes where.

The return is undersized.

Does each skimmer have a 2" line all the way to the equipment pad?

I would remove one pump and divide the water between both filters.

You can leave the main drain closed most of the time.

As long as the 3 skimmers are the only things on, the flow should be good.

Make sure that the skimmer weirs (doors) are good.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,437
Bedford, TX
00,

Skimmers and skimming is misunderstood by a lot of pool owners... Skimmers work because of the weir door action, and not because the pump is sucking a bunch of water out of the skimmer.. I run my pump at 1200 RPM, you can hardly see any water movement in the skimmers, when looking down from the top, but they work just fine. They are not really designed to reach out into the pool and pull stuff in.. They use the weir door and patience..

The weir door, in a way, makes the water in the skimmer appear to be lower than the water in the pool. Water, being water, will flow into the skimmer.. but not any water, it will be the surface water so that it brings all the debris with it. I use hair nets in my skimmers and know for sure how much stuff they collect.

I am not quite sure how your pumps are set up, but you should never have them interconnected on the suction (input) side or the pressure (output) side. You can have a thousand pumps, if that is what you want, but they each need dedicated input and output plumbing.

Good luck with your project.. Should work a little better with the correct MVPs.. :mrgreen:

Jim R.
 
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Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
7,176
Central California
Jim beat me to it. No plumbing expert here, and maybe resolving the multi-ports will solve the various flow problems. But it's not just a matter of separate pumps for skimming and vac/drain, as long as they both flow into a common return loop they're going to be compromised, unless you have only skimming, or only vac going on at any given point in time (which is what James is saying).

I like James' advice about eliminating a pump.

I'm wondering if this could be an alternative: your plumbing schematic shows two main drains. Do they each have two anti-entrapment drains teeing into them, so you have four drains total? If the two drain lines in your drawing are not functioning as anti-entrapment, I'm wondering if one of the main drain lines could be converted to a deep-water return. You replumb the three skimmer lines with three-way valves, so you can balance them properly, and run those through one pump that runs through one filter to the returns loop. One drain line and the vac line run to a three-way valve with actuator, into the second pump, through the second filter and return to the pool through the other drain (a deep-water return). That would give you the two independent loops that Jim describes. You could then run vac and skimmers at the same time, no problem. When not vacuuming, the actuator switches and you get suction from one drain returning to the pool through the other drain (the deep-water return). SWG, acid injector and heater go on the skimmer circuit. The circulation provided by the deep water return might help eliminate cold spots while heating.

Maybe that's harebrained, I've never actually seen that done, but neither have I seen all that you've got running into a single return loop. Just spitballin'... @JamesW or @Jimrahbe will know if there's something wrong with that idea.
 
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imported00

Member
Sep 23, 2020
8
Saint George, UT
No, that's definitely the wrong one.

There's a lot going on there. It's hard to tell exactly what goes where.

The return is undersized.

Does each skimmer have a 2" line all the way to the equipment pad?

I would remove one pump and divide the water between both filters.

You can leave the main drain closed most of the time.

As long as the 3 skimmers are the only things on, the flow should be good.

Make sure that the skimmer weirs (doors) are good.
Thanks again for the feed back!!!
1) Each individual skimmer has a 2” pipe returning to the equipment pad. Each skimmer line has an 2way valve at the pad to allow for suction adjustment.
2) I actually took off the doors because I thought it was impeding flow into the skimmer. I will replace the doors tomorrow. 3) I’m fine with removing the deep drain pump from service. It will save on electricity.
Thank you
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
33,301
Laughlin, NV
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imported00

Member
Sep 23, 2020
8
Saint George, UT
Jim beat me to it. No plumbing expert here, and maybe resolving the multi-ports will solve the various flow problems. But it's not just a matter of separate pumps for skimming and vac/drain, as long as they both flow into a common return loop they're going to be compromised, unless you have only skimming, or only vac going on at any given point in time (which is what James is saying).

I like James' advice about eliminating a pump.

I'm wondering if this could be an alternative: your plumbing schematic shows two main drains. Do they each have two anti-entrapment drains teeing into them, so you have four drains total? If the two drain lines in your drawing are not functioning as anti-entrapment, I'm wondering if one of the main drain lines could be converted to a deep-water return. You replumb the three skimmer lines with three-way valves, so you can balance them properly, and run those through one pump that runs through one filter to the returns loop. One drain line and the vac line run to a three-way valve with actuator, into the second pump, through the second filter and return to the pool through the other drain (a deep-water return). That would give you the two independent loops that Jim describes. You could then run vac and skimmers at the same time, no problem. When not vacuuming, the actuator switches and you get suction from one drain returning to the pool through the other drain (the deep-water return). SWG, acid injector and heater go on the skimmer circuit. The circulation provided by the deep water return might help eliminate cold spots while heating.

Maybe that's harebrained, I've never actually seen that done, but neither have I seen all that you've got running into a single return loop. Just spitballin'... @JamesW or @Jimrahbe will know if there's something wrong with that idea.
I have actually thought about do the very same plumbing you just suggested. I have three drain returns from the deep end. All three are have an anti entrapment “y” built in. One of the of those drains is used for the water slide/waterfall. It makes sense to have each filter/pump have its own return loop. Stop the hydraulic forces fighting each other. I don’t ever use the vacuum wall port so that line is available. I have a Polaris cleaning robot for the floor and walls but she is always cleaning the deep end. I have a vertical deep end drop off and it won’t come up to the shallow end. It’s too smart for its own good. I’ll have to post my robot issues in another thread and get sone advice!!!
Thank you.