Pool Plumbing Problems

[Hobie]

Hello all,

I have a 20,000 gal swimming pool with hot tub. It has been running about 5 years and has never worked quite right. My system includes a Hayward Northstar 2hp motor that runs the pool and spa combo. In the loop I have a De72 filter, Aquacal heat pump and Hayward h400 gas heater and Jandy Aquapure salt system. Controlling the whole think is Jandy automation. Normally the system draws from the main drain and skimmers and returns to pool returns and spa bubbler. When I activate spa mode 3 Jandy valves pull from the spa, water is sent through the gas heater instead of heat pump, and returned to spa jets. I also have a Hayward 1 hp for a waterfall. Pressure in the de filter is 20psi and I change powder at 30 psi.

The problem is that when I pull from 2 of 3 sources(main drain and skimmer or main drain and spa) the system works fine. When I go to one source(the spa is the worst) the pump slowly loses the prime and the pump is only about half full with water. It makes the spa unusable and the gas usage huge. If I can overcome this problem my wife and kids would be very happy!

The spa is plumbed with 2" pvc about 100 feet away from the pump and includes about 15 elbows. It has 5 jets.

A few questions:

1. I have been told that the pump is way overkill and I should change it. The recomendation is to go to 1hp 2 speed. Would that be enough? Good recomendation or is variable speed better?

2. I believe the plumbing run is too long and the pvc is too small. If I go t a 2.5 or even 3" and remove the elbows will it help. I can get down to 90 feet with 4 elbows. I can get to within 2 feet of the spa drains and jump to the bigger pipe and run it to the equipment. Can a pump be expected to run effeciently that far even with 3" pipe? I have 5 spa jets. Then what size pump should I get?

3. Since I believe the plumbing needs changing is there a better manner to plumb a pool/spa/waterfall combination?

4. I presently have a Jandy actuator that either feeds the heat pump or gas heater depending on whether I am in spa mode.Is it a good idea to run the heat pump and gas heater in series to increase efficiency of the heating(I would use the Jandy actuator as a bypass when they are not in use).

5.

I wish the system was designed properly in the first place but now need to reengineer. Moving all the equipment is the one issue that I really cannot change(about 90 feet run to the spa, and 30 feet to the pool). But the plumbing in the ground, pumps, and layout is all on the table. Thank you in advance for any help, advice or guidance.

Regards,

Useless hot tub

[Hobie]

I forgot to ask. If I change to supply lines to the pump to a larger size do I also need to change to return to the spa/pool?

[quantumchromodynamics]

Can you provide the following information?

01) What suctions does the spa have?

02) Does the spa have a skimmer?

03) How many main drains does the spa have?

04) What are the dimensions of the spa main drains?

05) Is the spa at the same level as the pool?

06) Does the spa spill over into the pool or is there an equalizer line that you plug to use the spa?

07) How important are the spa jets to you? Do they need to be strong?

08) Where does the 1 h.p waterfall pump get its water from?

09) How often do you want to use the spa?

10) When you switch to spa mode, do all of the valves turn completely?

11) How did the plumbing end up with 15 elbows?

12) How long do you run the pump each day?

13) What are your electrical rates?

14) Are you in California?

[Hobie]

Can you provide the following information?

01) What suctions does the spa have?

2 spa drains plumbed by 2" run approximately 100" with about 15 or so elbows to a Jandy 3 valve and to 2HP pump

02) Does the spa have a skimmer?

No

03) How many main drains does the spa have?

2

04) What are the dimensions of the spa main drains?

2" pvc with the same drain covers as pool. They are plumbed together

05) Is the spa at the same level as the pool?

About 2' higher with spill over.

06) Does the spa spill over into the pool or is there an equalizer line that you plug to use the spa?

Spill over

07) How important are the spa jets to you? Do they need to be strong?

yes

08) Where does the 1 h.p waterfall pump get its water from?

It received the water from the main drain line

09) How often do you want to use the spa?

2 times/week

10) When you switch to spa mode, do all of the valves turn completely?

Yes, 3 way jandy valve with actuators

11) How did the plumbing end up with 15 elbows?

Plumber initially put pipes side by side(5 or so abreast) right through a planter about 6" below ground. I told him they needed to be deeper. Also needed to plan for addition. Instead of digging all pipes deeper he just put extra elbows on to go under planter and planned addition. Hence 8 extra elbows.

12) How long do you run the pump each day?

As of now 8 hours, I am willing to change to longer period if a 2 speed would allow equal or less electric usage and equal or better cleaning performance.

13) What are your electrical rates?

0.121/kWH

14) Are you in California?

no

15. I am wondering if I should use 1 pump for pool/ spa bubbler/waterfall and other pump for spa jets? Thoughts?

[quantumchromodynamics]

My first concern would be the safety of having a 2 H.P pump pulling from just two drains when the system is in spa mode. There is a possible risk of suction entrapment that should be evaluated by a service person qualified in design and engineering. You may need to have an SVRS (Safety Vacuum Release System) installed.

The main drains should have the new approved covers and you need to know the design flow rate of the main drains to make sure that you do not exceed their design limit. The drains need to configured in such a way so that they cannot both be blocked at the same time.

01) What is the design flow rate of the spa main drains (per drain)?

02) What are the dimensions of the drains?

03) How far apart are the drains from each other (center to center)?

04) What is the design flow rate of the spa jets (Minimum and Maximum per jet)?

05) How many skimmers does the pool have?

06) How many main drains does the pool have?

07) Does the fountain pull from its own dedicated main drain?

08) How old is the fountain pump? Is it ready to be replaced?

09) What is the filter pressure when on Spa mode?

10) Are the spa drains Teed together and run to the equipment with a single 2-inch line or do they each have their own 2-inch line to the equipment?

11) Are you considering the spill over to be the fountain or is there a separate fountain?

12) What is the design flow rate of the fountain?

13) Is the fountain designed to give a sheer sheet of water or does it cascade down rocks?

14) Are you happy with the performance of the fountain?

It sounds like the spa suction plumbing is undersized, partially blocked and/or has an air leak. What happens to the pump when you switch to spa mode? Does the pump begin to strain and get loud?

If the spa suction is a single 2-inch PVC pipe with (15) 90s then it definitely needs to be replumbed. The (15) 90s are equivalent to at least an extra 90 feet of straight pipe. We will need to know the design flow rate of the main drains and the jets to determine the correct piping size. The returns will also need to be replumbed.

Spa jets are typically in the 15 to 20 gpm range for optimum flow rate. For 5 jets, that would be 75-100 gpm.

Suction maximum flow rate for 2-inch pipe = 63 gpm. 2.5-inch = 90 gpm. 3-inch = 138 gpm.

Pressure maximum flow rate for 2-inch pipe = 80 gpm. 2.5-inch = 120 gpm. 3-inch = 170 gpm

When you replumb, you will want to make sure that there are no air leaks in the line, that the actuators are moving the valves fully from one position to the next and that there are no obstructions in the plumbing.

Since you already have Jandy automation, I think that the 1.5 or 2.0 H.P Jandy ePump is going to be your best option (Size depends on spa design flow rate).

It will work with your automation and you can select the right flow based on what you're doing. For Spa mode, you would want high flow rate to power the jets. For circulation, you can choose the optimum flow rate. My preference for filtering is to run longer at lower flow rates. I would rather run at lower speed for longer times than high speed for shorter time.

I would use a higher speed when the pool was in use to give better circulation and to keep the skimmer weirs from banging due to waves from people splashing.

Dropping the speed in half uses about 1/4 to 1/5 of the energy due to the flow dynamics. I don't like the water to sit for any length of time without circulating. Low speed will save you money and give you better performance.

You will have to make sure that the flow rate of the pump is enough to operate the heater and chlorinator. 30 to 35 gpm should usually be enough. I you can also program your system to increase pump speed when the heater wants to turn on.

You should be able to use the ePump for the fountain as well. You would just divert the return water to the fountain.

http://www.jandy.com/ePumpPdf/SL5171.pdf

http://www.jandy.com/epump.php

Sorry if it seems that I am asking a lot of questions, but I think that these details are important to getting the best design.

Putting the spa on its own system is an option. You could use a two-speed pump for the spa. High speed for jets and low speed for circulation. You could put a separate filter and heater so that you could operate the spa separately and keep it hot so that you could use it whenever you want. You could use valves to share the pool heater with the spa if you didn't want to buy a separate heater.

[Hobie]

01) What is the design flow rate of the spa main drains (per drain)?

If am not sure. 2 drains plumbed together. Same drain covers as pool(I will put the new covers on). I believe 2" pvc

02) What are the dimensions of the drains?

03) How far apart are the drains from each other (center to center)?

3'

04) What is the design flow rate of the spa jets (Minimum and Maximum per jet)?

Not sure.

05) How many skimmers does the pool have?

2

06) How many main drains does the pool have?

4 all plumbed together

07) Does the fountain pull from its own dedicated main drain?

no, I believe it was t'd off the main drain line

08) How old is the fountain pump? Is it ready to be replaced?

Pumps are about 6 years old. Fountain had 1 hp that i just swapped with 2 hp. 1 hp pump is still good so I will replace 2hp.

09) What is the filter pressure when on Spa mode?

When I go to spa mode, the pump begins to strain, the water gets milky and it cavitates and loses prime. The pressure drop to 5-10psi.

10) Are the spa drains Teed together and run to the equipment with a single 2-inch line or do they each have their own 2-inch line to the equipment?

Unfortunately I believe they are teed together.

11) Are you considering the spill over to be the fountain or is there a separate fountain?

I have a spa spillover to the pool and i also have a waterfall/groto that uses an individual 1hp pump.

12) What is the design flow rate of the fountain?

not sure, whatever looks good. The 1hp is probably overkill there also. But it looks good.

13) Is the fountain designed to give a sheer sheet of water or does it cascade down rocks?

14) Are you happy with the performance of the fountain?

It sounds like the spa suction plumbing is undersized, partially blocked and/or has an air leak. What happens to the pump when you switch to spa mode? Does the pump begin to strain and get loud?

Yes, that is my problem. I need a complete redesign plan. Plumbing and pump. I am willing to do some inground pipe work and can access the spa lines with some work. I am quite handy and am capable of doing the labor but want to make sure the design is sound prior to doing all the digging. I will need to take the covers off the spa drains but I believe all work was done with 2" pvc. Jets are probably in the 15-20gpm range. I have a hayward DE72 filter, Aquacal H155 heat pump, hayward h400 gas heater, Jandy Aquapure 1400 and some Jandy 3 way valves in line also.

When I replace the suction line of the spa to a larger diameter, is getting to within 2 feet of the spa adequate? Maybe for safety it would be a better idea to run a seperate line from each spa drain. A pain to dig under the spa but it would alleviate issues.

Putting the spa on its own system is an option. You could use a two-speed pump for the spa. High speed for jets and low speed for circulation. You could put a separate filter and heater so that you could operate the spa separately and keep it hot so that you could use it whenever you want. You could use valves to share the pool heater with the spa if you didn't want to buy a separate heater.

I don't mind my current setup of using 2 pumps(1 for pool/spa and 1 for waterfall) but if there is a better way to accomplish things I am not against changing things. I like the idea of using a 2 speed or variable speed pump to run the pool longer and slower. Then bump up speed for spa mode.

Thanks for everything

[quantumchromodynamics]

The first thing you will need to decide is how much flow you want for the hot tub. 75 gpm will probably generate low to medium pressure from the jets. 100 gpm would probably deliver pretty good pressure. You will have to check the jet specifications to be sure and decide what would work best for you.

Once you determine the flow rate that you want, you will have to replumb the suction and return. Getting to within 2 feet of the spa will not be adequate for the suction. 2-inch is limited to 63 gpm. It must be at least 2.5 in all of the way for up to 90 gpm and at least 3-inch for up to 138 gpm.

For pressure, 2-inch would be borderline at 75 gpm. I think that the return to the jet line should be 2.5-inch.

Pressure maximum flow rate:

Diameter.............GPM

2-inch....................80

2.5-inch................120 gpm.

3-inch...................170 gpm

It definitely sounds like there is an obstruction in the spa suction line. Hopefully you can find something when you replumb. When you switch to spa mode, does the spa suction valve open all of the way?

I think that the 2.0 H.P Jandy ePump will work well and will operate the pool fountain and the spa.

Your system is fairly complex and would require quite a bit of detailed planning and design to get the best results. I recommend that you hire a professional to advise you and review all plans before you begin working. I am advising you based on a limited amount of information. Without being able to visit the actual job, there are important details that I will probably miss. I also do not have the time to fully develop a proper design plan.

A proper, detailed design plan will give you the best overall results including safety, efficiency and performance.

You will have to determine whether or not the spa main drains are adequate to safely deliver the flow rate that you choose. The main drains should be Teed together to make sure that they are hydraulically balanced.

Since the waterfall already has its own pump, I don't see any reason to change it. I'm not sure why it had its own pump in the first place. I would think that the regular return could be diverted from the wall or floor returns to the fountain except when the heater was on because that could cause a lot of the heat to be lost through evaporation.

[quantumchromodynamics]

Here is another pump you should consider. It will give you better performance if you want good jet action. It also comes with a built-in SVRS safety system.

The SVRS provides an extra layer of safety. Some of the new safety rules apply to commercial pools and spas, however, the exact same laws of physics apply. If it's a good idea for a commercial spa, then it's a good idea for a residential spa.

I think that you are going to have a hard time getting 100 gpm for the jets by the time you pull the water from over 100 feet from the spa, push it through the system and then 100 feet back to the spa even after you upgrade the plumbing.

It would help if you could develop a system curve after upgrading the plumbing. To do this you could use your existing pumps to see what kind of flow rate you get and what the pressure and suction readings are.

You could use your 1 HP pump and your 2 HP pump to see what the readings are at both horsepowers. This would give you more data points and a better graph of your system curve.

You could see if the upgraded plumbing would allow you to use the Jandy or if you should go with the Pentair Intelliflo.

[Pool Clown]

First, I would check the o rings in the suction side diverter valve (pump loosing prime in spa mode). If they are Jandy 3 way valves, they make "diverter kits" that replace the diverter as well as all the o rings for the valve. You may want to rebuild the other two as well (if they are leaking). The suction side wont leak water as it is always pulling (a vacuum).

It sounds like your filter pump drives the jets in the spa, so you're kind of stuck with that size pump IF you want to run the jets with any force. The best advice is to keep the filter clean, this will help keep the flow rate up as much as possible for the jets to function the way you want.

A two speed pump, or a variable speed would work for you, but you need to know what it would involve to integrate it into your automation... Money!

Not only is the pump at the high end of cost nowadays (meaning 2 or variable speed), but you would either need to go out to the equipment and adjust speeds for the spa (each time you want to use it), or get a controller that will integrate your ability to control speeds through your Jandy controller. Not cheap, although Pentair is now releasing an upgraded version to their original controller that is less expensive than the original one they put out a couple of years ago.

But for the time being, check those valve o rings to see if that will get your spa working, at least for now.

[Hobie]

My spa main drains are 3' 10" apart, center to center. The opening is 6" currently with sp 1048 covers. The pipe is 2" glued to the drain and then the 2 are teed together. I could dig under the spa and step up to 2.5" then 3" with a run to the pump about 90 feet and 1 T 4 elbows(or substitute 45 degrees for each elbow)and then 3 way valve to pump. Of course I need to step back down to 2" before the 3 way valve at the pump. For the return I could do essentially the same except jump to 2.5" for the length of run. Would a pump be able to handle this and is the spacing of the drains safe enough?

Would you recommend I use the Jandy Epump or the Pentair Intelliflo svrs. I have Jandy Aqualink RS-8 with firmware L. With Jandy I need the upgrade firmware and with Pentair I lose features.

[quantumchromodynamics]

I think that if you switch the drain covers to the WG1048E Drain Cover, you should be in compliance.

WG1048E Drain Cover.

Ratings: Floor = 125 GPM. Wall = 72 GPM. Open Area =8.1 square inches

I think that an additional layer of safety is necessary due to the large amount of suction that is being supplied by only main drains. If one of the covers were to come loose or if one drain were to become blocked, then it could create a serious safety hazard. You can add an SVRS, such as the Vac-Alert or you can use a pump that has a built-in SVRS, such as the previously mentioned Intelliflo. SVRS is not absolutely necessary. I would consider SVRS to be extra cautious. You will have to decide if it is worth the extra expense.

The IntelliFlo is available without the SVRS. I think that the Jandy automation will control the IntelliFlo. You may need to upgrade your firmware if it is an older version.

The Jandy ePump is rated at 2.0 H.P and it has a S.F (service factor) of 1.35 making a total of 2.7 H.P. The IntelliFlo is rated at 3.0 H.P with a S.F of 1.15 for a total of 3.45 H.P.

The IntelliFlo will do about 100 gpm at 85 feet of head. The Jandy will do about 100 gpm at 70 feet of head.

The Pentair IntelliComm II Interface Adaptor allows Non-Pentair Control Systems to control IntelliFlo and IntelliPro Variable Speed and Flow Pumps

http://www.pentairpool.com/pdfs/IntelliCommIIOM.pdf

http://www.pentairpool.com/products/automa...adapter-408.htm

The velocity of the water going through the suction lines must not exceed 6 feet per second. Here are the maximum allowable flow rates for the suction plumbing. (Technically, for legal compliance, the velocity should not exceed 6 feet per second. From a physical standpoint, a short run of 2 inch pipe will not cause too much loss. Short sections of 2 or 2.5 inch pipe may be unavoidable).

Diameter.............GPM

2-inch....................63 gpm.

2.5-inch................90 gpm.

3-inch...................138 gpm

Once you get the piping upgraded, you should try the system with your current pump to see what the performance is. You should use a flow-meter to determine the flow rate. You should use a vacuum gauge to determine the vacuum pressure and you can use the pressure gauge to determine the pressure or head loss for the return. You can evaluate the jet pressure to see if it will be sufficient.

The information will help you determine your system curve. You will use your system curve to determine which pump to get.

You don't necessarily need to get a new pump. Your current problem is that there is some sort of problem with your spa suction line.

The main reason I recommended a new pump is that 2 HP is highly inefficient for a 20,000 gallon pool. For normal circulation, you could drop the flow rate down to about 35 gpm. That would save a lot of electricity. The variable speed pumps also use a permanent magnet motor (like those used in hybrid cars) instead of a traditional induction motor. Permanent magnet motors are fundamentally more energy efficient.

You should do the following:

01) Disassemble the diverter valve to make sure that it is not clogged and that it is not sucking in air.

02) Replace the main drain covers with the new approved covers.

03) Check inside the main drains for any obstruction.

04) Replumb the suction and returns to the spa. Size to be based on the flow rate you want.

05) Test system for performance to develop a system curve and determine the correct pump size.

06) Check the system carefully for air leaks. Check the valves, pump lid, pump drain plugs etc. Check where the fitting screws into the front of the pump.

You will have to investigate the integration of the pump with your automation.

Do your jets look like these?

Flowmeter.

[Hobie]

Hello,

Hello,

I checked the pressure on ny system and this is what I found.

1 Everything open(all supply, heater selector, and returns) and the pump is now a Hayward NS 1.0 hp.(I switched the 2 and 1 hp around).

Pressure on Hayward de72 is 15psi. When I returned all the flow to only the spa jets pressure increased to 20psi and jet performance was marginal at best.

2. When I went to spa mode and the valve was almost at the closed position the pump began to lose prime and when closed to spa side, the basket was about half full with lots of water coming in and pressure was now 14psi. Jet performance even worse.

The jets are the ones you show. The adjustable and pulsator is what I have. Are they Waterway brand?

All your recomendations look good.

1. I will replace the drain covers

2. Looking at my RS-8 it lookl like I have only 1 channel left. I know with the Epump I need the Aqualink firmware upgrade but I am getting conflicting info about if I also need the upgrade with the Pentair Intelliflo. If I go with the Jandy Epump it should interface OK. But if I go with the Pentair Intelliflo VS and the Intellicom 2, I believe that I need a channel for each speed I want. That would be only 2 speed as I understand the Jandy Aqualink/Pentair Intelliflo interaction. Still not clear on the interaction of Jandy Aqualink and Pentair Intelliflo. What would your choice be?

3. SVRS is something that sounds nice. Definately a pro in Pentair's corner but concerns of integration issues. Vac-Alert definately an option.

4. I have checked all drains( ran a snake through), looked for leaks and have found no problems.

5. I plan to replumb. Since the spa is the worst this is what I plan. Spa drain to be plumbed together with a T. 2"x2"x3". Run 3"pvc with sweep 90's as far as possible to pump. Plumb Aquacal H155 and Hayward h400 inline for effeciency. Plumb return to jets with 2.5" with sweep 90's and tie into spa jet return line at spa. Run will be bout 90 feet for both.

6. Put either Jandy Epump 2.0hp and firmware upgrade to P. Or Pentair Intelliflo VS or VF w/or w/o SVRS and Intellicom 2 to communicate to Aqualink RS-8. Still wonder what interfaces better.

7. Put Blue-White flow meter after pump(unless I get Intelliflo VF)

[Hobie]

I have 2 pumps. a Hayward NS 2hp for pool/spa and a Hayward NS 1 hp for the waterfall. A local pool professional said the 2hp was way too big and that all I needed was a 1hp. He also told me about how much I was spending on electric.

I decided to swap the pumps around to see the effect(the same things happen with the 2hp btw). Everything I have been posting is since the 1hp is on the system. I just played with it again and notice that when I use the Hayward Navigator pool vac from a vac port, I am unable to draw only from the vacuum(I still need to utilise a small bit of skimmer) or I lose prime.

If I pull from the skimmers the system works fine. From the main drains a small bit of air. From the skimmer only, it begins to cavitate, and spa is a total loss.

So in addition to changing the spa suction(I will use 2" flexi pvc from each spa drain and bring together in 2x2x3 Y Wye joint) using 3"pvc and flexi pvc I can shorten run to 85'. The spa return will be similar but with 2.5 " The main drain and skimmer will always be used in combination so I can live with the main drain limitation. And increase the size of the vacuum line to 2.5" with a run o 59".

If I use the Epump the unions are 2.5" so I also plan on changing the supply 3 way valve to a Jandy Large Neverlube. Everything on the outlet size is 2" so I will leave it 2" pipe untill after the salt cell . After the 3 way valve I will increase size to 2.5" to the spa return using 2.5" pvc and 2.5"flexi pvc for turns. Should I use Cpvc after the heater because of temperature issues?

Looking back at the plans for the pool it even states that for 6fps flow max and 86' run I need 3" pipe. 118' run I need 4" pipe. I wish I had looked at the plans and watched him closer!

[quantumchromodynamics]

Yes, the jets are Waterway.

For automation, the best thing to do is to e-mail Jandy and Pentair with the questions to get the best, most up-to-date information.

Due to the long pipe runs, I think that using 3-inch for the suction and returns would be best. Use hard pipe instead of flex.

The 2-inch valves will take a 2.5-inch slip fitting on the outside. This makes the valve a 2.5-inch valve. You should avoid 2-inch wherever possible. You should be able to avoid 2-inch almost entirely.

The pump is losing prime under high suction probably due to a very small air leak that only leaks under strong vacuum. The high vacuum is being caused by the inadequate and possibly obstructed plumbing. Replumbing the entire suction should take care of the air leak. The plumbing should be pressure tested to check for leaks.

Can you get under the spa to where the two drains T together? If you can, you should use a 3-inch T with 2.5-inch reducers where the two 2.5-inch lines will connect. You should use 2.5-inch instead of 2-inch, if possible. You should use all hard pipe instead of flex. Use CPVC at the heaters.

I think that the heaters should be run in parallel, not in series. In parallel, you can run both at the same time if you want. In series, you can only run one, because the heat from the first heater would reduce the efficiency of the second heater and it would interfere with the second heater's thermostat.

The heaters should have a flow switch installed to make sure that there is adequate flow through the heaters before they start. The pressure switch that comes with the heaters is not adequate for heaters plumbed in parallel.

The salt cell should have a check valve bypass to allow excess flow to bypass the cell.

Once the plumbing is redone, you should run the system in spa mode in several configurations to determine the system curve characteristics. You should get a vacuum gauge and a flow-meter for 2.5 or 3-inch plumbing.

The Blue-White F-300 requires 14 X the pipe diameter of straight horizontal pipe for correct operation. The 2.5-inch flowmeter requires 35 inches of straight horizontal pipe. The 3-inch flowmeter requires 42 inches of straight horizontal pipe. The flow-meter should be put after the filter to avoid debris getting stuck in the flowmeter and causing it to malfunction. Putting it after the filter will insure that the water going through the meter is clean.

Test configurations:

1) 1 H.P pump, jets in.

2) 1 H.P pump, jets out.

3) 2 H.P pump, jets in.

4) 2 H.P pump, jets out.

Record vacuum reading, pressure reading and flow-rate for each configuration. We will need this information to determine which new pump to get.

Can you get new jets for the spa? It sounds like they are easily replaceable. That will help eliminate defective jets as a contributing cause of the poor performance.

Once you get the test data, we can determine which pump size to get. Information from Jandy and Pentair should help us decide which pump will work best with your automation. I think that we should use the Jandy, if possible, but we may want the Pentair for its higher power.

Important note:

There are new laws and regulations pertaining to suction safety. It is important that you make sure that all work complies with all applicable state and federal laws including the Virginia Graeme Baker Pool and Spa Safety Act. The work should be certified by a pool professional as complying with all applicable laws and regulations.

For drain safety, it is important that the drain covers are properly secured and intact. If the drain covers are ever loose, broken or missing, then the spa should not be used until the covers can be fixed.

People should be instructed that the drains are not to be interfered with in any way. They need to be instructed not to block or even touch the drains. People with long hair need to be instructed to keep their hair away from the fittings. Everyone should be shown how to turn the pumps off in an emergency.

I recommend an extra layer of safety due to the large amount of suction that will be pulled exclusively from the mains drains when in spa mode. SVRS is expensive. You will have to decide if it is worth the extra cost.

[quantumchromodynamics]

I think that the Jandy ePump should integrate better with your Jandy Automation.

In addition, if there is any type of problem on a mixed system, Jandy can blame Pentair and Pentair can blame Jandy. With both being Jandy, then Jandy would have to solve the problem.

As I previously noted, the Jandy ePump has less power, so we need to avoid head loss everywhere we can. 5 feet of head here and 5 feet there adds up quickly. For spa use, the only components that we have to go through are:

01) Spa main drain grates.

02) Spa suction lines

03) 40-50 gpm through the gas heater. (Min. = 25. Max. = 125)

04) Spa return lines.

05) Spa jets.

Here are some ideas to reduce or avoid head loss:

01) Use 3-inch hard PVC for the spa suction and return.

02) Put a 2.5-inch bypass on the filter, heater(s) and chlorinator cell to bypass flow over 40 gpm.

03) Many 2-inch fittings will take 2.5-inch slip fittings on the outside. Use the 2.5-inch side for better flow. (2-inch Jandy valves take 2.5-inch on the outside.

For spa use, the water does not even have to go through the filter or the chlorinator. By the time you try to push 100 gpm + through the multiport, filter, heater and chlorinator, the head loss will be pretty high and it will put unnecessary stress on the components.

I don't think that it's necessary to automate everything, however, that is up to you. It will cost more and it's more complicated, but if that's what you want, then it's definitely doable.

[Hobie]

I have checked for air leaks around valves, fittings and the pump. No luck. Looking at the original plans I see there is a dual suction inlet system and atmospheric vent system. Due to the strong suction(long length and small pipe size), when in spa mode as the valve closes to 100% spa suction I immediately lose prime and basket is 1/2 full. That might be the problem(suction so great that it pulls from vent), I will check when I get home. Even if I have a stone or something in the line I now see the plans(and everything I have learned from all of you) that the pipe size is way too small for that long of a run(max flow rate, pump and spa jet requirements) enlarging the plumbing should take care of everything.

I will not use flex pvc as I didn't want problems in the future. Using flex pvc on the corners allowed a shorter run, and using solid pvc will be closer to 95". Should I use 4" on suction side(for the majority of the run) and 3" on the return to the spa? A few extra dollars is worth it to me.

I plan to change the 5 spa jets. Any recommendation of a good quality? A mix of spinning and others.

Your recommendation of the Jandy Epump makes very good sense. I don't want compatability issues and hopefully with all the plumbing changes, it will be adequate for my system. Since I have a Jandy Aqualink rs-8(2 channels left) and all the actuators this is the cheapest for me. I will run the tests you recommend.

Regarding the bypass valves for the heaters and salt cell. Are there automatic ones that work on flow(your idea of 40 gpm), or do I just use a ball valve to adjust it manually?

Your idea of bypassing the filter and salt cell is interesting. Our house is the go to house for the neighborhood. Lots of kids and they love the spa. If the system can I would like to keep both due to the load water.

With the original plans having the vent system, I might retain that. Otherwise the Vac-Alert would be nice.

[quantumchromodynamics]

The atmospheric vent system is probably an SVRS. I think that is important to have with all of the kids that use the tub. It is important to also instruct the kids about drain safety and to make sure the kids are properly supervised.

Your SVRS should be set to trip somewhere between 10-15 inches of mercury (4.9-7.37 psi) (11.3-17.0 feet of head). Your SVRS should begin to trip at 60-75 gpm. (Assumes about 190 feet of 2-inch pipe. 100 feet of pipe + (15) 90s = about 190 feet total). So, it makes sense that your SVRS would be tripping.

Using 100 feet of pipe at 100 gpm, you will have 2.3 feet of head loss using 3-inch pipe and 0.6 feet of head loss using 4-inch pipe. You can see a chart of Friction head loss per 100 feet of PVC pipe here.

You can also use the calculator here using a design coefficient of 145.

I think that using 3-inch pipe should be adequate for the suction for 100-110 gallons per minute at 100-120 feet. It wouldn't hurt to use 4-inch on the long runs, but it won't give you a lot of benefit.

I think that using a 2.5-inch Jandy NeverLube valve manually would be the easiest for the bypass. The bypass would keep about 35-40 gpm going through the filter, heater and chlorinator. There would be about 60 gpm going through the bypass.

____________________________________________

Note: 100 feet of 2-inch pipe with (15) 90 degree fittings would not even allow 100 gpm of flow, no matter how big the pump was. Each 90 is equivalent to about 5.7 feet of straight pipe. See the chart here.

The head loss would be about 34 feet. It is physically impossible for suction to exceed 33.9 feet of head.

[quantumchromodynamics]

I checked the head loss data for the main drain covers. Assuming 110 gpm, that would be 55 gpm per drain. The head loss for 55 gpm is about 0.906 feet of head.

[Mark]

Ok third time I edited this post. The numbers that are being used were confusing. There is no way you would get 100 GPM on this plumbing set up even with a 2 HP pump.

If I run the setup through my model, I get:

1 HP NS Pump - 75 GPM @ 64' of head but the suction would be about 16" Hg.

2 HP NS Pump - 82 GPM at 78' of head and the suction would be about 19" Hg.

So it would easily release the SVRS.

[Mark]

Next if I model 3.0/2.5" plumbing with the Jandy JEP 2.0:

111 GPM @ 62' of head

With 4.0/3.0" plumbing

122 GPM @ 57' of head

These are estimates only.

[quantumchromodynamics]

Note: This was in reference to the suction head only.

I had rounded off the length to 190 feet and used 2.00 inches for the inside diameter, which gives 34.5 feet of head loss for the suction, which would be technically impossible.

Using the more accurate 100 + 15(5.7) = 185.5 feet and 2.067 ID, gives 28.701 feet of suction head.

Water will begin to boil when the suction reaches about 33.1 feet of head at 20 degree C (68 degrees F).

Water will begin to boil when the suction reaches about 31.72 feet of head at 100 degrees F (as in a hot tub).

I don't think that a 1 or 2 H.P pump is going to be able to pull a vacuum of 28.7 feet. It would begin to cavitate before that.

_____________________________________________

I think that it is also important to note that due to the high velocity and high number of 90-degree fittings, the water would significantly depart from laminar flow.

The calculations are dependant on laminar flow. Once the flow becomes turbulent, the resistance to flow can increase significantly.

[Mark]

That's why I changed my response. I realized you were talking about the suction. Anyway, I don't think the suction is that high but high enough to open the vent he may have that is acting like a SVRS.

[Hobie]

It appears that it is beginning to come together. I plan to start digging this week and upgrade pipe and pump.

Things I plan to change:

1. Spa plumbing suction to 4" and return to 3". Large Jandy 3way never lube and 3" to pump.

2. 2.5" on pool vac line and skimmer line.

3. 2.5" from pump to filter, heaters, Aquapure

4. Bypass on both heaters.

5. New drain covers on pool and spa

6. New Waterway spa mini-jets

7. See if I can tie in existing SVRS system to spa suction, otherwise check on Vac-Alert

8. Install Blue-White F300 on 2.5" pipe after filter and before heater. I will have dia x 10" before meter and dia x 4 after meter.

9. See how system runs with 2hp and 1 hp pump. Check pressures and determine which pump I get(I am leaning to the Jandy epump and firmware upgrade because of compatability issues and Mark's figures). I really do appreciate that.

10. What do you think of having spa return to a manifold and then to individual jets for even flow? Overkill or good idea?

11. Does it matter where spa blower joins the spa returns(near equipment or near spa)? Laminar flow issues?

This is what I have put together from all your advice. Does this sound like a reasonable plan of action now or do you have any more advice or changes I should think of? I sure don't want to go through all of this and miss something just to save a couple of bucks.

Just wanted to say thankyou again for everyones guidance and expertise.

When plumbing the system is there any guidlines you might have? ie. elbow butted up to Jandy 3 way valve or sould there be a set amount of distance between joints? I plan to run 3" pipe to pump supply(suction) in the length of 5 x diameter(15").

[quantumchromodynamics]

4. Bypass on both heaters.

I think that you should have the bypass so that it will bypass the filter, heater and salt cell so that you can limit the flow through those to about 35 to 40 gpm and about 60 to 65 gpm can go directly to the spa without going through the equipment.

10. What do you think of having spa return to a manifold and then to individual jets for even flow? Overkill or good idea?

The spa jets should be symmetrically plumbed for equal pressure. You would run 3-inch to near the tub then into a manifold and then to each individual jet.

11. Does it matter where spa blower joins the spa returns(near equipment or near spa)? Laminar flow issues?

The blower typically goes into an air-line that connects to a venturi fitting that is connected to the top of the inlet of the jet body. Does your blower just pump into the spa jet line?

When plumbing the system is there any guidlines you might have? ie. elbow butted up to Jandy 3 way valve or sould there be a set amount of distance between joints? I plan to run 3" pipe to pump supply(suction) in the length of 5 x diameter(15").

For plumbing, you want to make sure that the water has as smooth of a path as possible. Try not to have the water making too many turns right next to each other. Having two 90s right next to each other causes a lot of turbulence.

[Hobie]

Bypassing the heaters are ok but if I bypass the filter and salt cell when I leave spa mode, what is the best way to route water back through the filter and salt cell when the pump returns to a low flow(Jandy epump)?

Currently I think they are plumbed together. When I dig then I will see how to plumb to a manifold.

I don't recall how the blower is plumbed. It never really worked either. I guess I shall see how he plumbed it when I dig it up.

I will put as much space between the elbows as possible. If I can find decent pricing on sweep elbows that is what I will use as much as possible. That should help with turbulance issues as much as possible.

Looking at the Waterway catalog I think I have teh Mini Gunite jets. With that system it shows the body accepts 2"pvc and reduces it to 1.5" to the jet. I have been unable to find a manifold that accepts 3" in and 2" out.