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TheGoose
07-21-2011, 09:44 AM
Pool Info-IG Gunite approx. 18,000 gallons. Recently installed Hayward Swimpure SWCG (up to 40,000 gal)
1-HP Pentair Whisper Flo and Tagelus 60D Sand Filter.

I have been battling water cloudiness for awhile now. Setting aside all the chemistry aspects of the pool for the temporary time being, do you think my filter/pump combo is right or wrong? I bought and installed both myself about 2006, and then this year replaced the bearings in my motor.

It seems that even when my pool chemistry is good, and the water has a good color, there is always a cloudiness or blur in the water. I changed my sand earlier this summer, and it helped some. I'm on the verge of going back to a DE Filter now that my skimmers are operational (long story). The filter shows delta-P over time, as you would expect, and when I backwash I do get the typical dirty looking backwash water. I am almost certain than when I backwash I am losing sand, and I noticed that when I changed the sand that the level was a little low. I am trying to keep my backwashes down to a minimum.

Open to suggestions and comments.

BigDave
08-02-2011, 12:52 PM
Is your pump 1 or 2 speed? Is it an Up rated or Full rated model?

PoolDoc
08-02-2011, 03:24 PM
The maximum LISTED flow rate for a TA60 is 60GPM; the maximum flow rate for GOOD effluent water quality is 35 - 40 GPM. When you run the filter at the LISTED flow rate or higher, you will force fine debris THROUGH the filter and back into the pool. But, at 30 GPM, a sand filter with proper filter sand will produce water clarity close to what a DE filter can achieve.

A 1HP Whisperflo will generate somewhere between 60 & 80 GPM on a typical layout with 2" pipe. If you replace the pump internals with the parts from the 1/2 or 3/4 HP models, you will lower your flow, lower your electrical use per hour of operation, and improve the quality of water leaving the pump.

On an 18,000 gallon pool, operating at 35 GPM, you'd need to run your pump at least 8 hours.

BigDave
08-02-2011, 03:56 PM
What parts would need to be changed? Impeller, Volute, Motor? Just Curious.

PoolDoc
08-02-2011, 04:13 PM
See https://www.pentairpartners.com/productcatalog/pdf/PumpParts_US.pdf , page 458 and 459

It appears that you might be able to change only the seal (#16) and impeller #(28). It looks like the diffuser (#13) is the same in all of the pumps below 3HP.

TheGoose
08-06-2011, 01:32 PM
Hey guys thanks for the great replys. I definitely think that I am under-filtering my water. My original pump was a 1.5 HP with a swim-quip DE filter of approx. the same size (physical size). When I had the DE filter it was a real pain because my skimmers were non-functional at the time and I could only use the main drain. I had to load the filter by popping the basket lid off the pump, washing the DE into the suction piping with a water hose, and then re-starting (and priming) the pump. I had to do this 5-6 times to get all the DE in. The whole reason for switching to the sand filter was to avoid this problem (plus the original pump/tank were 20+ years old).

My original skimmer piping was the white flexible PVC, which collapsed and was unusable. I think that putting chlorine tablets in the skimmer baskets had some type of effect on the skimmer piping. The material was just ate up from the inside. I had them fixed last summer, they had to dig under the deck to do the job. At first I thought we would have to cut the deck around the skimmers out but they were able to dig under the deck. That made a huge difference in the way the pool operated. Imagine having to hand-skim all the leaves etc. out of the pool and only using the main drain. Could've kicked myself in the butt for waiting so long to get them fixed but I had so many other things wrong with the pool that it just got pushed back.

My pump is a straight up 1-HP, no dual speed. Since installing my SWCG a few weeks ago my water is looking much, much better, but I can still tell that the clarity is not where it should be. I don't know why I had such a hard time keeping chlorine in the pool but since installing the SWCG my water stays blue and I no longer have those little algae clingers in the corners etc. That seemed like the battle that would never end.

I'm thinking about switching back to DE. I don't mind the occassional cleaning or loading the filter every 2-3 weeks if it means my water will look better with less effort.

Thanks for all your helpful input, I appreciate the responses.

Watermom
08-06-2011, 01:39 PM
Have you tried adding a little DE to your sand filter? That helps with filtration and may just do the trick for you.

Adding DE to a Sand Filter (http://www.poolforum.com/pf2/showthread.php?t=3742)

TheGoose
08-06-2011, 02:29 PM
Yeah, that is my next experiment.

TheGoose
03-23-2012, 02:04 AM
Update to my thread:

My 1-HP Pentair (motor) bit the dust this spring. I was running the pump intermittently, getting ready to do some pre-spring maintenance. I did not use the pump over the winter. It ran for a few days before crapping out.

I'm trying to decide whether to replace the motor only and keep the same pump, or change the pump/motor and filter back to DE.

Pool season doesn't start until late April/Early May so I have time to think.

What would you do?

PoolDoc
03-23-2012, 06:16 AM
What would you do?

Depends.

1. Does the cost of a new pump & filter fit your budget? Or, do you need to minimize costs?
2. Does your piping need to be corrected, at the pump? (Send pictures of your current layout to poolforum@gmail.com)
3. Do you have a lot of debris land in your pool, so that your skimmer really needs to be running much of the time?
4. Does it matter to you (or your family) whether your pool is REALLY clear, or just clear. (Sand filters are lower maintenance, but lower clarity as well.)

Watermom
03-23-2012, 04:56 PM
Sand filters may be slightly lower clarity, but for most people, I doubt that would be able to tell the difference. I have always had a sand filter and my water always appears extremely clear. Simple maintenance is hard to beat. Just my nickel's worth.

TheGoose
03-23-2012, 11:21 PM
Budget is not a huge concern.

I don't think my piping has to be corrected much, if any. Small changes of course to re-route the plumbing but I'm plenty capable.

I do have lots of trees etc (from neighbors yard) hanging over my pool, but I kinda like the shade so it's a catch-22.

I had a DE filter once before. Changing out the DE about once a month is no big deal. Pulling apart the filter and cleaning once or twice a season also doesn't seem like a lot of work for the return. I wouldn't mind going back DE, I just want to make sure that I don't do all the work but still have murky water.

What size pump/DE filter would be appropriate for a 18,00-20,000 gallon pool?

I really like my water clear. It doesn't have to be crystal, but it seems that there is very little in-between. It either seems to be crystal clear, or murky. Not much in between.

CarlD
03-23-2012, 11:35 PM
Isn't this a 325# sand filter? If so, there is NO WAY it's not sufficient for an 18,000 gallon pool. You just may have the wrong pump.

I think it's really time to explore your pool chemistry.

TheGoose
03-23-2012, 11:55 PM
What pump do I need then?

CarlD
03-24-2012, 12:05 AM
I can't think this late at night, but I find it hard to believe that ANY 1hp pump made is straining THIS filter! I'm thinking it's a chemistry or plumbing problem, not a filter/pump sizing problem. Fellow mods and senior contributors?

PoolDoc
03-24-2012, 08:18 AM
Carl, the Whisperflo is a more efficient pump than average, so a 1HP WhisperFlo moves more water than a 1HP SuperPump. Plus, the Whisperflo is often sold full-rate, so you are comparing a 1HP full rate Whisperflo with 1HP uprate (=3/4HP full rate) SuperPump.

The give-away that this is almost certainly the problem is early in the thread, when Goose comments that he's

almost certain than when I backwash I am losing sand, and I noticed that when I changed the sand that the level was a little low.
Flow is high enough to push dirt through sand BEFORE it gets high enough to blow sand out of the filter during backwash.

Goose, since budget isn't a big issue, I'd recommend the following changes:

1. Replace the TA60 with a TA100 filter. That will allow flows up to 70 GPM without overloading your filter. However, better clarity and longer filter runs will come with LOWER flows.
2. Replace your motor with a 2 speed 1HP motor . . . and run on low almost all the time.

If you want a timer, Intermatic has one that will switch speeds. But, using a toggle switch may be all you need. With a 1HP Whisperflo and a TA100 you'll be running 20 - 30 GPM on low speed! You'll probably need high only to backwash and vacuum.

Alternatively, if you want optimize things to the max, you can go with a Pentair Intelliflo, which is a 2HP Whisperflo with special motor and variable speed drive. I believe it comes with a built-in timer.

HOWEVER, please send photos of your piping at the the pump and filter before you start, and let me or Mark (mas985) look at it before you do. There are a number of piping practices that many pool builders follow that are HORRENDOUSLY bad, hydraulically. Correcting these can greatly improve your efficiency.

Here are links:
2 speed motor (A1 Pool Parts) (http://www.a1poolparts.com/-strse-Motors--dsh--Replacement-cln-Multi-dsh-Speed/Categories.bok)
WhisperFlo pump (http://www.pentairpool.com/pool-pro/products/pumps-inground-whisperflo-high-performance-pump-193.htm)
Intelliflo (Whisperflo w/ VFD) (http://www.pentairpool.com/pool-pro/products/pumps-inground-intelliflo-variable-speed-pump-430.htm)
Tagelus filters (http://www.pentairpool.com/pool-pro/products/filters-sand-tagelus-top-mount-filter-176.htm)

TheGoose
03-28-2012, 11:14 AM
Thank you very much for the info. My pump/tank set-up is pretty straight forward. Two lines coming up from the pool, into a jandy 3-way valve. One from the skimmers, one from the bottom drain. Discharge from pump straight to tank, then tank discharged back to pool with a 1" line coming off for the booster polaris pump. The piping is all 2" on the inlet, but I believe it goes down to 1.5" on the discharge to the tank. Tank discharge I think goes back to 2" at the ground level where it goes directly to the return jets.

I installed the complete pump/tank combo a few years ago myself along with the electrical components so I'm pretty competent in that area.

Thanks for all your advice. I'm definitely thinking about the dual speed. What is your opinion on going back to DE as opposed to sand? I don't mind the extra work if it means my water stays clearer.

PoolDoc
03-28-2012, 07:40 PM
DE will give you clearer water, and will reduce your pools tendency to get algae. BUT, if you do get algae, cleaning up is MUCH easier with a sand filter -- one algae episode can result in as much DE use as you'd otherwise use in a year. So, I don't recommend DE for folks who tend to neglect their pool every so often.

TheGoose
03-29-2012, 08:40 PM
All great advice. I think I'm gonna leave my pump/tank alone and go with the 2-speed motor on my existing pump.

TheGoose
04-13-2012, 10:58 AM
FYI I installed the 2-speed motor a few days ago. Now I'm circulating the pool, which turned into a swamp while the motor was out.

I added about 25 gallons of bleach and am backwashing almost daily. I haven't yet tried the low speed because I don't have a toggle switch yet.

The motor came with three connections : L1, L2, and A. The diagram was stated so that you could connect I believe L1 and A up it would be low speed, L1 and L2 would be full speed.

Am I correct in thinking that a jumper between L2 and A would allow me to switch the speeds? In other words, incoming power to L1 and A, with a jumper with toggle switch between A and L2 to switch between low/high.

PoolDoc
04-13-2012, 11:30 AM
Please send the exact motor make and model, so we can look up the manual and diagram -- I don't want to answer, and I don't want anyone else to answer, without seeing that diagram. You could lose a new motor that way!

TheGoose
04-13-2012, 01:46 PM
AO Smith

1 HP 230V B2982

http://www.aosmithmotors.com/products/distributionpoolandspa/default.aspx?id=569&terms=B2982

I am fairly competent when it comes to installing things like controls and motors so you don't have to think I'm gonna fry myself doing this.

I guess we can't easily post pictures but high is L1, then you have L2, and then you have A for low speed. I'm thinking that I should connect one incoming wire to A and one to L2. For full speed I install a switch between A and L1.

PoolDoc
04-13-2012, 02:17 PM
Sorry, if I offended you . . . but I've worked with too many electricians who couldn't wire a DPDT switch for a 2 speed pump, for me to take anything for granted. Here's the connection drawing:

https://lh5.googleusercontent.com/-jFrTY9QBnKQ/T4hth6_JduI/AAAAAAAACUQ/nvghfYL_ToA/s800/AO%2520Smith%2520B2982%25202-spd%2520wiring.jpg

Based on that drawing, yes, can toggle between high & low, and switch speeds. Remember, that you need a 15A MOTOR or INDUCTION rated switch. And, if you place the switch external to the motor, you need to attach a warning label indicating that the switch does NOT disconnect power to the motor. Intermatic has a DPDT time clock you can use, that's not much more than an SPDT clock.

TheGoose
04-13-2012, 02:30 PM
That's the picture I was going to post.

You didn't offend me, I was just trying to relay that you don't have to do the typical dummy comments like "shut off the breakers" and such. I work with pumps/motors everyday, some of which are thousands of horsepower.

Thanks for the warning about the 15 amp switch, it makes sense.

PoolDoc
04-13-2012, 02:35 PM
Actually, I typically include the "DPDT" acronym as a test ;) . If you'd reacted with a "Huh?", I would have launched the "Hire an electrician; you can't safely do this yourself" boiler plate.

However, I've learned the hard way knowledge in one area does not bleed over into a related area, for many people. I can't tell you how many graduate chemists I've dealt with who get confused by pool chemistry . . . or who find Chem_Geek just as hard to follow as I do! So, telling my you work with 1,000 HP motors doesn't tell me you know how to wire a 8A 230V motor, in a wet area, using the crappy conduit sold for residential and light commercial use! (Hint: always, ALWAYS use a wired ground!)

TheGoose
04-13-2012, 02:39 PM
OK, one last question for now:

Since I was using my regular 1-HP pump at about 12-15 hours per day, what should I run this new configuration on low speed?
I'm hearing that if it will pump ~60 GPM at full speed, it will still do ~20-30 GPM at low speed, but uses way less electricity to pump at the low speed. So I'm supposed to be able to run twice as long on low as I did on high and still save money. Is this a true statement or is it more marketing? Also I've read reports both ways that it increases the efficiency of your filter since the velocity of the water is so much slower that the filter will work better.

Thanks.

PoolDoc
04-13-2012, 03:19 PM
Sand filters work MUCH better at low flow, but you have to backwash at high flow.

To actually know what your flow will be, I'd need pump curves AND a detailed layout on your equipment. But 1/2 the flow for 1/5 the electricity is probably in the range.

TheGoose
04-18-2012, 10:45 PM
I've got some pictures I would like to send ya or post if there's a way. I know how to do it in other forums, but I noticed you have pics disabled in this one.

PoolDoc
04-18-2012, 10:50 PM
send them to poolforum@gmail.com, and I'll post them -- I'll look to see if there are problems with the permissions in this section at the same time.

TheGoose
04-19-2012, 10:25 PM
Sent the pics. Subject "The Goose Pool Pics" or something similar.