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Thread: Bernoulli: the implementation

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    Bernoulli: the implementation

    Let's say I've decided on 2.5" suction and 2" returns for my (please, please) soon-to-be pool. Rather than just telling the builder to shut up and do it my way, I'd like to understand exactly what I'm asking for. Besides a bigger stock of 2.5" pipe, what changes to my builder's normal stock of parts and supplies will there be from the usual 1.5"-and-2" install?

    • 2" to 1.5" reducers for the returns[/*:m:2funbwdx]
    • 2.5" to 2" reducers for the skimmers & main drains[/*:m:2funbwdx]
    • Large size valves (2" inside, 2.5" outside)[/*:m:2funbwdx]
    • 2.5" couplings[/*:m:2funbwdx]
    • Large size tees (?)[/*:m:2funbwdx]

    What else? Are there any places where they'd have to convert all the way from 2.5" down to 1.5", and can they just use reducers in series for that or is there a special 2.5" to 1.5" part? Would building the manifold at the equipment pad be vastly different other than the bigger valves?

    Also, will mandating separate runs to the pad for the returns (4 total) cause a problem with too many pipes in the trench, or anything like that? Does the trench have to be wide enough for all the lines to lie side-to-side, or can they be stacked?


    Hydraulically mundane 20x40 rectangular polymer (~30K gal.), IntelliFlo VS+SVRS pump, IntelliChlor IC40 SWCG, Pentair CCP520 cartridge filter, LED light, 2xDeck Jets, SR Smith Turbo Twister slide

  2. Back To Top    #2

    Join Date
    Jul 2007
    Suwanee, GA

    Re: Bernoulli: the implementation

    It would help if you mentioned the size of your pool and the size of the proposed pump.

    I did all the reading I could prior to our pool build and my PB was still way smarter than me. I suggested a larger pump and more returns and he convinced me in a smaller pump (1hp) and two returns and he was right. The 1hp is plenty and the 2 returns provide great circulation.

    I have 3 2" suctions and a single 2" return as well as a 1 1/2" return for the Polaris. My pool is super clean and has been for the last 4 years.
    21k gal SW, IG Gunite PebbleSheen, 1HP Jandy, Jandy 340 filter, Polaris 280, 17' fiberglass slide w/ 2HP pump.

  3. Back To Top    #3

    Join Date
    Mar 2007
    San Rafael, CA USA

    Re: Bernoulli: the implementation

    If you have separate lines, then 2" for them should be fine. 2.5" would only be needed for runs from the pump that split to separate 2" lines later and wouldn't be needed if you run separate lines all the way close to the pump (unless those lines were extraordinarily long). That whole discussion in the other thread for larger piping was mostly about not using 1.5" lines for individual lines to fixtures (including suction lines) and not using 2" lines for single piping to/from the pump (i.e. at full unsplit flow rates) where these lines were not short. Note also that in your case with 4 returns, the flow is split by 1/4th so there will be less head loss than only having 2 or 3 returns. More is not necessarily better for number of returns unless your pool has an odd shape.

    There don't seem to be inlets/returns for 2" pipe as far as I can tell, but there are inlets/returns for 1.5" pipe with 1" eyes (see here for example) in which case you'd need a PVC Schedule 40 2" to 1.5" reducing coupling, preferably with a smooth tapering of the coupling (as shown here). Since there will likely be a 90 degree elbow not too far from each return, you could instead use a 2" x 1 1/2" Reducing Elbow (#11 listed here) since the length of 1 1/2" line will be short.

    As crabboy notes, it would be good to know the size and shape of your pool, the size of pump you plan to get (both HP and service factor), what type of filter, and whether you will have a solar system. If you can afford it, a variable speed or variable flow pump such as the IntelliFlo would give you the greatest flexibility, but such pumps are more expensive (especially if you add a controller to it). A 2-speed pump would be the next best, but not as efficient (though less expensive). When I got my IntelliFlo, my PB had never installed it before and I don't regret getting it for one second, and he was a very good PB -- while not everyone knows everything, ask him why he objects to anything you suggest as he could very well point out legitimate considerations.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

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    Re: Bernoulli: the implementation

    I'm planning on a 20x40 rectangular with 2' radius corners and an 8' center step on the shallow end. The pool will have two skimmers and three pool returns, plus a pair of return jets in the step. The pump will be a Pentair Intelliflo VS+SVRS without automation, and the filter will be a Pentair CCP520 cartridge. At some point, there'll be either a solar system or a propane heater, or both. The builder is leaving room for them to be plumbed in in the future. The equipment pad will be close to the pool; no more than 20' from one of the deep end corners. There will plumbing for two Pentair Deck Jets and an SR Smith Turbo Twister slide. The jets will each have a 3/4" line in (under?) the concrete, teed together and run back to the pump with 1 1/2" pipe. The slide will also have a separate 1 1/2" line to the pump. The builder strongly recommended against shutoff valves for the pool returns. The jets, slide, and step returns (I think) will have their own valves.

    The builder has patiently reasoned with me and helped talk me out of every **** fool idea but two. I still want 2" return lines instead of 1.5", and I still want separate return runs all the way to the pad. He's pushing back hard on those last two things, and I want to be able to clearly explain myself.


    Hydraulically mundane 20x40 rectangular polymer (~30K gal.), IntelliFlo VS+SVRS pump, IntelliChlor IC40 SWCG, Pentair CCP520 cartridge filter, LED light, 2xDeck Jets, SR Smith Turbo Twister slide

  5. Back To Top    #5

    Join Date
    Nov 2009
    Indialantic, FL

    Re: Bernoulli: the implementation

    Given the relatively short distance from pad to pool and running separate return lines from pad to pool, I think 1.5" is enough. If you were to run a single line to the pool, especially if looped, then (IMO) it should be 2".
    Geometric 16X36', 16K gal, shotcrete, exposed aggregate plaster, acrylic coated concrete deck/cantilever coping;
    Pentair equipment suite (EasyTouch w/wireless, 2 Intellibrites, Intelliflo VS-3050, C&C 200 Filter, IC-40 SWG);
    Heliocol solar panels, Rocky's Roller, Blue Diamond robot

  6. Back To Top    #6
    guamguy's Avatar
    Join Date
    Feb 2010
    Guam, USA

    Re: Bernoulli: the implementation

    What's wrong with shutoff valves for the pool returns? Mine are looped, but I have a valve that shuts off the entire loop, and it's nice to have for increasing the pressure to my waterslide.
    12,800 gallon IG plaster kidney-shaped pool, waterslide, 800 gallon spa.
    1HP 2 speed Sta-Rite pool pump, 1.5 HP Sta-Rite spa jet pump. 2 skimmers, 1 main drain
    Purex-Triton TR-60 325 lb.sand filter. 2" Plumbing, Intex SWCG, TF-100 test kit.
    Link to pics of my pool!

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