Going to larger pump. Other considerations?

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
Well, after fighting this thing for three years I had a pool service come out to give me an estimate on monthly service. The company owner came out and his first comment was that my pump isn't big enough and I don't have enough circulation (something I'd suspected all along). He didnt' try to sell me a pump and when he saw that I'd just replaced the 1HP recently, said I could probably buy it online cheaper than he could sell it to me. He said a 2HP would probably be the right size for my pool but not knowing the quality of work that went into the fittings recommended I go to a 1.5HP. Would most of you agree with this assessment?

Anything else I need to consider? Saving energy (or at least offsetting the usage of the bigger motor) would be nice.
 
G

Guest

Unlike a BBC in place of a SBC engine for your car (you thought I missed your avatar, didn't you :cool: ), bigger is not better for a swimming pool pump! Pipe diameters, length of run, various items that add head to the pool (solar, heater, etc.) all impact pump performance. If your plumbing is too small, the pump cannot operate efficiently. If the flow rate on your filter (for example) will not handle the flow of a pump, then you have another problem.

How many gallons (approx) is your pool? I would take the gallons and divide by 360 (the number of minutes in 6 hours) to get a gpm rating required to turn your pool over in a 6 hour run time. Slower moving water cleans better, and forcing water through the filter (we like to do that with our Reverse Osmosis membranes, but that's different!) too fast is inefficient.

What is the size of your pipes? There are flow rates associated with pipe diameters also, so that may have an impact on pump size.

A 2 HP pump is awfully big, and expensive to run :shock: I would check your gpm requirement and then decide what size pump you need. I would also consider a 2 speed or multi speed pump as opposed to a single speed pump. I would also consider where your pool guy got his info from, and if he is just trying to sell you something instead of trying to take care of you.

Oh, one last thing; I'd go for the SBC. That should keep the fuel bill down :lol:
 

Davegvg

LifeTime Supporter
Nov 30, 2008
337
I agree with Sim.. (with the exception that my SBC puts out 500HP http://www.youtube.com/watch?v=RYE_gwoQcZ8)

Curious - What discoveries have led the both of you to the conclusion you don't have enough pump?

Have you tried upping the run time to 24x7

A 1.5 HP pump is 1500 watts of continuous energy consumption...

Ive come to the conclusion that I can keep my pool surfaced skimmed pretty clean and keep the chlorinator happy with flow at about 200 watts of power consumption at 15-17 hours of run time.

I need to bump this substantially for solar to be effective and bump it to around 350-400 to run a cleaner or skimmer accessories , but for standard filtration that's enough.

You have a large pool for sure, but not enormous.

Talk to us....


Uncle Dave
 

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
Hello,  fellow motorheads!  That Buick Grand National avatar and my Screen Name should tell you that I don’t always believe bigger is better (my last GN made just over 500hp from 231 c.i.d.  Gotta love turbos and intercoolers!)  My ’36 Chevy street rod started out being built around a GN motor but I’ve since switched to an LS1 (hoping to turbocharge it later).
 
That being said, my pool has too many “dead zones” that just don’t get enough circulation.  They become obvious when the algae starts.  I’m all for using only as much as is needed but I’ve got to rectify this problem.  I really don’t  think this was an “upsale” situation because the guy didn’t even try to sell me one from his store.  My pool is 8’ deep if that matters.  I currently run the pump 12hrs/day.  Haven’t tried 24/7.  My thinking is that it’s mainly an issue of water pressure rather than volume of turnover. 
By the calculations from poolcalculator.com my pool is approximately 30,000 gallons.  That would give me an 83 GPH turnover requirement. 
The pipes are 1.25” at the equipment, I assume they are that size throughout the run.  There are 4 returns, two skimmers and two main drains.  There is an electric pool heater inline as well.  From the equipment to the farthest return is probably about 75’.
 
Thanks,
Richard
 
 
Richard T. Gautier
Chevron Operations
Blending and Shipping
"D" Crew
 
Pascagoula Refinery
Chevron Products Company
250 Industrial Road
Pascagoula, Ms 39581
Tel  228-938-4502
Fax 228-938-4504
 
 

Davegvg

LifeTime Supporter
Nov 30, 2008
337
Love the v6 turbo mills. Love turbos, love cubes, love it all! Those buick turbos can be leaned on to make sick power.
show us a pict or 2 of your project ......please.....

Those pipes are small, and considering you are pushing two skimmers and 4 returns through holes that small id tend to agree you likely need more pump. Youve also got a pretty long run dragging you down as well.

Problem is you may not be able to move much more water than you are now due to pipe sizing.

Have you aimed your eyeballs to give a circular flow to the skimmer? Sounds simple but many people don't get this right.

Id try moving to a 24x7 pump run before upping the pump size, you may find that this does the trick with carefull aiming of the returns.

If you do up the size Id go to a 2 speed, or preferably variable speed. The variable flow pentair is trick as well.
With a variable you are covered and can find the optimum spot for performance and economy.
With a 2 speed you can get close, run it on high during the day and low at night to keep the top free of floating Crud.

Tell me what you have for a filter- this could be slowing the flow tremendously if not right.


U.D.
 
G

Guest

4.1 Buick with TBI in my '68 Jeepster. Not cheap motors to work on, but I love 'em! Got a 225 Oddfire that I'm gonna put in Mama's '66 Half Cab one day.

You have a big pool (30,000 gallons is not typical, as you probably know!), and you could technically use a bigger pump, although your pipe diameters are fighting you. You just can't move that much water properly through that small of pipe.

Like Dave said, I think I'd go with a multi speed pump and increase the run time as opposed to a bigger pump. You'll be happier in the end, and probably spend less on electricity as well (leaving you more money for more GN goodies!).
 

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
It appears that the pool company that built it undersized the pump and piping in the original construction. I don't want to overstress the pipes but an increase in water velocity is what I think I need. I'll go to a 24/7 run time for now and see how it does. I'll post a pic or two of the car later. I'll try from my iPhone but don't know is it'll work
 

PoolGuyNJ

TFP Expert
May 20, 2007
3,192
South Central NJ
1-1/4" is an unusual size for pool plumbing. An S244T filter takes 1-1/2" plumbing. This is pretty well maxed out at 75 GPM. A 1-1/2 HP pump is as large as this plumbing and filter can handle. A 2 HP will be starved.

What size are the actual eyeballs in the return fittings? They should be no less than 3/4" openings. I tend to point the eyes slightly down and to one side so as to promote circular motion of the current(s).

How are you feeding your pool's chlorine demand?

How are you testing your water?

What are your current levels?

I really don't think a larger pump is called for.

I do suspect that that at least one of the following is causing the fight:

1) Misdirected returns
2) High CYA levels and or incorrect chlorine levels
3) Not testing accurately

All three are correctable, especially now that you have help, and I don't mean the service, but rather us.

Scott
 

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
PoolGuyNJ said:
1-1/4" is an unusual size for pool plumbing. An S244T filter takes 1-1/2" plumbing. This is pretty well maxed out at 75 GPM. A 1-1/2 HP pump is as large as this plumbing and filter can handle. A 2 HP will be starved.

What size are the actual eyeballs in the return fittings? They should be no less than 3/4" openings. I tend to point the eyes slightly down and to one side so as to promote circular motion of the current(s).

How are you feeding your pool's chlorine demand?

How are you testing your water?

What are your current levels?

I really don't think a larger pump is called for.

I do suspect that that at least one of the following is causing the fight:

1) Misdirected returns
2) High CYA levels and or incorrect chlorine levels
3) Not testing accurately

All three are correctable, especially now that you have help, and I don't mean the service, but rather us.

Scott
I shouldn't have tried to work from memory. All of the piping is 1.5"

The eyeballs are pointed in a fashion similar to what you suggest. They appear to have approximately 3/4" diameter holes.

Pool Pilot SWG is what's supposed to feed the Chlorine demand. It has NEVER done so adequately and adding shock weekly has been the only way I've maintained a decent FC level.

TF-100 test kit

1- Eyeballs are correctly oriented (I've tried several configurations, btw)
2 - CYA is currently 70
3 - My testing is fine

I don't think my problem is a lack of water "turnover" as much as it is a lack of sufficient return nozzle velocity to eliminate the "dead zones".
 

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
Cell is an SC48 (they originally installed an SC36, after suffering with that for a year they replaced it and said "oops, sorry." :grrrr: Cell is now about 1.5 years old. Salinity is 3000ppm.
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
Sinistr....what's your FC level and target? Nice project by the way! If circulation is an issue you can try maintaining fc 1-2ppm above the recommended levels.
 

guamguy

LifeTime Supporter
Feb 26, 2010
388
Guam, USA
Nice ride :-D I'm still a Chevy guy, but how does a '03 Toyota Tundra 4.7L V8 turbo strike 'ya? :cool:

Off topic, but I'll post pics of the motor in another thread
 

PoolGuyNJ

TFP Expert
May 20, 2007
3,192
South Central NJ
Dealing with what is:

Deep return #1(next to skimmer) should point down a bit and towards the wall, just shy of the dead zone.
Deep retrun #2 (opposite the deep skimmer) pointed towards the floor below the skimmer.
This will set up a counter-clockwise flow rotation.

Shallow return #1 (next to deep skimmer) should point to the wall about 1/2 way towards the shallow skimmer.
Shallow return #2 (next to the shallow skimmer) should point to the wall between the two dead zones.
This will create a clockwise rotation of the flow.

The two circulations will work together at the slope. This should prevent dueling circulation patterns. I would use 3/4" eyes in the returns.

Aim for an FC of at least 4 and ideal at 5 ppm.

The returns and skimmer locations could have been better placed when it was built.

Scott
 

Davegvg

LifeTime Supporter
Nov 30, 2008
337
Cool project, and thats an awesome pool there boss - my personal fav a dedicated shallow and deep area.

I should never do math while sitting home sick a 1.5 HP pump is actually 1119 watts- still a lot.

With poolguy NJ's directional advice and a 24/7 pump run you may find that to be enough- if not i think you are spot on about the 1.5 HP pump.
The stuff that gathers on the top because of poor circulation will whack your free chlorine for sure and getting the top clean will improve your ability to hold the chlorine.

I myself would get a jandy epump 1.5 hp version to do this. I like the pentair pump a bit better, with the exception of the pump pot size, but they are all wickedly powerful and if you have any kind of a logic issue or somehow the pump gets up to full speed without a throttle the full 3 HP could be dangerous to your plumbing. You can run it at full speed during the day and cut it back to 1 HP or less at night.

The epump has the same rare earth magnet tech and will give you cost efficient run times and with a 1.5 HP max even if the pump somehow defaults to full speed you wont risk bursting anything.

(curious - is there a 2 speed pump with 1.5 max and rare earth tech? if so that would be enough rather than a full variable setup)

I think your chlorination "problem" would be ameliorated with better circulation.

Im really surprised you can run any kind of pressure cleaner off a return line in this setup- I wouldnt think it has enough oomph unless you block the other eyes and even then....

As much as I hesitate to ever add "more pump" I think you have this nailed.


Uncle Dave
 

SinistrV6

Well-known member
Sep 6, 2008
111
Mississippi Gulf Coast
PoolGuyNJ said:
Dealing with what is:

Deep return #1(next to skimmer) should point down a bit and towards the wall, just shy of the dead zone.
Deep retrun #2 (opposite the deep skimmer) pointed towards the floor below the skimmer.
This will set up a counter-clockwise flow rotation.

Shallow return #1 (next to deep skimmer) should point to the wall about 1/2 way towards the shallow skimmer.
Shallow return #2 (next to the shallow skimmer) should point to the wall between the two dead zones.
This will create a clockwise rotation of the flow.

The two circulations will work together at the slope. This should prevent dueling circulation patterns. I would use 3/4" eyes in the returns.

Aim for an FC of at least 4 and ideal at 5 ppm.

The returns and skimmer locations could have been better placed when it was built.

Scott
Thanks, Scott. I'll try that setup. It's similar to what I have set up now with the exception of your #1. Instead of two circulation patterns, I have attempted one large one (not really feasible in an "L" shaped pool.). I agree with you on the returns and skimmer locations not being optimal.
 

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