Question about laminars

[Ponytrekker]

Hello, I am in the process of installing 5 Pentair Magicstream laminars and I am looking for some help on gauging the correct water flow requirements. I have a Sta-Rite (Pentair) Intellipro VS which has a 2" intake and is dedicated solely to the laminars. The Pentair Magistream laminars each require a minimum of 10 GPM with 16 feet of head at the Laminar for maximum performance. They are located fairly close to the eq pad 10 feet away so I have very little pressure drop. I have plumbed a 10 foot 1 1/2" pipe from the IntelliPro to 1 1/2 inch manifold which feeds 5 1" ball valves, each of which feeds a laminar thur 1" flexible PVC. The laminar housings are encased in a concrete deck adjacent to the pool.

My question is how to correctly estimate the total requirements. Is it a case of simple multiplication (5 laminars x 10 GPM for a total GPM of 50) and also (5 laminars x 16 feet of head for a toal of 80 feet of head). If this is correct, all I have to do is make sure my pump can provide 50 GPM with 80 feet of dynamic head. The Intellipro manual has a performance chart which
indicates this is possible at approximately 3450 rpm, or just slightly less.

Is there anyone here who can advise if this approach makes sense, given that I should have very little pressure drop from the pump, or else advise me otherwise.

There is a secondary question which depends on the answer, it has to do with whether or not I need to install a master 1 1/2 ball valve before the manifold to reduce overall pressure. I know that the 5 1" ball valves can be used to compensate for individual adjustment but I do not think I need the master 1 1/2 ball valve because I don't think I will have excess pressure, but obviously that depends on my assumed multiplication theory. There would also be the issue of how to relieve excess pressure, if it should exist because I would not want early pump failure. I suppose I could use a diverter valve instead of a master ball valve and tap into a pool or spa return, which is possible and would require an additional check valve, that is possible but it is a plumbing PITA.

Please let me know if you have advice relative to my questions

Thanks in advance and thanks for making this a great forum, I just signed up last night.

Ponytrekker

 

[Melt In The Sun]

I expect it will be more than enough power! The total head doesn't add up mathematically, it's conceptually the same as electrical resistance. I can't tell you exactly what the head will be, but with those short runs I can't imagine it not working. It would be much better to have larger pipes, but it's probably too late for that now.

 

[racket]

A 1/2hp whisperflo can run 8 laminars without too much trouble so an intellipro will be more than enough. I seriously doubt you would need to run it at a rpm higher than 1700.

 

[Just-a-PB]

VS pump is great because you can dial in exactly what you want. Really comes down to how far you want them to shoot.
You have way more power then you will ever need.
Your set up will work fine.
Ball valves make it a little harder to do fine tuning.
Big question is:
1)Do you have a cartridge filter on this set up, if not add one.
2)Make sure you disconnect the laminars and shoot clean water out prior to hooking it up in the box.

 

[Ponytrekker]

Thanks all for the answers so far. PB- You don't miss a thing. I'm considering the Sta-rite Posi-clear PXC75 because of the small footprint. I left it out of the discussion but certainly it's part of the equation. The 10ft. 1 1/2 pvc line I have in place is flexible PVC, so it is no problem splicing in the cartridge, and that was the plan. For readers not familiar with the laminars, the devices themselves disconnect from the laminar housing and internal water supply via a coupling. I've rigged a temporary connection to these couplings that lets me flush the discharge safely back into the pool, not the drainage at the bottom of the laminar housings, which I would have flooded out in no time. This gives me ample flushing time, not to mention the time to fool around with the Intellipro settings (or dialing it in). I didn't want to take the chance of hooking everything up and overpowering the jet nozzles with too much flow, thus my original posting. BTW, I also use a cork to plug the electrical conduit at the bottom of the laminars. So far so good. I will flush again after I install the cartridge filter, then pull the laminar cords thru, hookup the water supply couplings and I will be more comfortable with the first test runs. After I have things where I like them, then I will tackle the Magicstream LED/transformer/programming issues. What has been holding me up on the filter cartridge issue has really been specing out things like finding a 20 micron filter in a device that doens't impede GPM. Other issues like not blowing out the jets with to much GPM and a general lack of information on how to put it all together have really forced me to move slowly but carefully on this project. For readers who are considering retrofitting laminars, it is no small feat. Mostly because of the need to have a drainage line that is 24 to 30" inches below the top of the laminars, and then you need additional negative slope to make sure your drains work. I was lucky that when we built the pool, I had placed a drainline for a planter, so we lucked out. You also have to have the ideal hardscape to mount the laminars so they are aesthetically practical, in our case, they're behind the artifical rocks that line the backside of our pool, and the five laminars reside between our grotto and pool slide, so we just had the perfect place to put them. We also had the luxury of an additional intake line to use, so we didn't have to timeshare with another intake. We used what was originally a Deep Heat return, which was an additional pool return designed to spread solar heated water into the deepend. We never noticed that anyways so we turned into an intake for the laminars. Finally, you need to understand the placement and throw of the jetstream, to make sure your end product looks like it belongs. It is alot easy to install laminars if you are doing a new build, but for retro-fits, you really have to have the right situation.

If anyone has suggestions on filter cartridge that would be good choices, I am still a week or so away from making a decision so I'd be glad to hear what you have to say. Thanks.

Pontrekker

 

[viberama]

I have 3 laminars running off a Intelliflo VS pump with a pipe run of about 30 feet and they run fine at 1500 RPM. You should have no problem with your set-up.

 

[Ponytrekker]

Thanks all for the input. Yes my Intellipro VS3050 is driving all 5 laminars fine. A big surprise was that, when using the IS10 Spa side control with its 10b pump control, I can adjust the laminars arc height while in the Spa. At 1700 RPM they are about 3 feet high. With each additional push of a button they rise up about a half-foot or so. At 2300 they are a massive 10-12 feet high, yet keep the water stream intact. The 1" ball valves came in handy to balance the height, with just a very slight adjustment needed. For my filter, I settled on a high flow Pentair Dynamic series cartridge filter, which plumbed in line and it's about the size of a large chlorinator. All in all, this has been a great water feature to retrofit.

Thanks again for contributing,
Ponytrekker

 

[Melt In The Sun]

That looks great; congrats!

 

[Cloneman315]

I am trying to figure out what I need to do with my laminars. I have a 16x32 pool with a vf pump. One skimmer two returns all 2 inch. When I turn the valve to the two laminars it is way to much pressure for the laminars. I have the vf pump turned down as low as it will go 15gpm. I try to turn the two ball valves going to each laminars down but the pump does not like that and wants to ramp up. If I run the returns and the laminars I can fine tune it and just run the jandy valve half way splitting water to the returns and the laminars 50%. The problem that seems to happen since a it's a 180 deg valve it opens to the laminars and turns the returns off using the automation. I am wondering if I need one of the new intellivalve so I can lock in the setting on the valve that works the best and limit its travel.