Redoing my equipment: Help me select a (2 speed?) pump

[Flot]

Quick background: S. Florida in-ground pool, 13k-15k gallons. I have a skimmer and a vac line, and two returns, each plumbed 1.5" PVC.

Current equipment is a Sta-Rite P2RA5D-180L 3/4 HP wired 220v. My pool store mentioned this was "really more than 3/4". No idea on that. Also have a Hayward C800 cartridge filter.

I use a GW9500 Great White cleaner and run the pool 6-8 hours a day through the cleaner, (rarely the skimmer) - I have more than enough suction and never had water issues using 3" tabs.

I'm adding a Hayward AQR Salt System (T15) this weekend, and went ahead and ordered a new C900 filter to go with it. While I'm in there and doing a bunch of PVC work, I figure I have a good opportunity to change out the pump as well. From reading on here, it seems like a 2 speed may make the most sense for me - what would be a good replacement, size-wise, for my current pump?

I want something that will keep the flow high enough on low that the SWG keeps up - however I am a little concerned about anything providing MORE suction than my current setup - I get plenty of water movement with the current pump and frankly don't want to jinx the 30 year old plumbing. (although I did replace as much as possible when I remodeled a while back)

 

[Bama Rambler]

Welcome to TFP.

If you want to stick with the same style pump Pentair makes a PEAXYE-181L which is a 1 - 1/6 HP pump. That would probably do what you need.

 

[mas985]

Your current pump is up rated so it is the equivalent of a 1/2 HP full rated pump so I am not sure what the pool store is talking about. But not surprised either.

Since your current pump is about as small as you can get, have you thought about just changing out the motor for a two speed? You would only need a new motor and seal which would cost less than a new pump plus you would not have to touch the plumbing. A Century B2980 should work.

 

[bobodaclown]

Hello,
I've got a similar pump. Mine was wired for 110V. I just swapped out the motor, a single speed for a 2 speed. I picked up a toggle switch and wired it inline with the mechanical T101 timer. It will prime on low, just takes a bit longer.

You can take off the motor off the back section of the pump easy enough. I brought the motor to a local Pinch a Penny and they mounted the motor with new seal for about $30. Then I wired it up myself.

I picked up a re-manufactured 2 speed motor for less than $200 so far so good. I was looking at the 2EZ motors they have a timer built in for a reasonable price. Others have reported good luck with them.
Here's the link 1HP: http://www.americanbestpoolsupply.com/detail/129176.htm
Here's the link 3/4HP: https://www.americanbestpoolsupply.com/detail/13495.htm

(personally I'd get the 3/4 HP) Save $15

Not sure if you have the 1hp or 3/4 impeller. Looked it up:
P2RA5D-180L 3/4 115/230/60/1 A100DLL C105-92PS C1-216P

You've got the same impeller/diffuser I have. Here's the owners manual: http://www.pentairpool.com/pdfs/DuraGlasOM.pdf

I'm using a 3/4 115V 2-speed motor. I get approx 53 GPM on high and 21GPM on low.

 

[Flot]

I'm not really a fan of the current pump - it has been fine mechanically but getting the lid to seal is an adventure every time, even after new o-rings and goop.

I'm shocked to hear this is an 'uprated' setup as I've got an average size older pool and seems everyone else I know has 1+ HP pumps in theirs.

I'm already ripping apart the plumbing - something with a newer better basket would make me happy. Would a 1 HP two speed make a dramatic difference in my power consumption? My labor is free to do the swap and not a big deal, although also needing a new timer may complicate things.

I'll try to measure my actual GPM rates, (time to empty a 5 gal bucket?) I frankly can't imagine needing anything bigger.

 

[mas985]

A 1 HP may be a larger pump than you have now and will not only draw more power (on high speed) but also have higher suction which seemed to be a concern of yours.

Measuring flow rate with a 5 gallon bucket is not very accurate. I can get closer with just a description of your suction side plumbing (pipe sizes, number pool to pump runs, and distance pool to pump) along with the filter pressure and the pump height relative to the water level. But it really isn't necessary.

A two speed pump that has about the same head curve as your current pump is the Hayward MaxFlo SP2307X102. A couple other choices are:

Pentair Superflo SF-N2-3/4A - A little smaller than your current pump
Pentair Superflo SF-N2-1A - A little larger than your current pump

 

[bobodaclown]

Pool pump is one of those cases where bigger isn't better. Going with a two speed motor you use approx. 1/3 of the power but get 1/2 the flow. It's a good energy savings.

Some reading about pumps: pool-school/pool_pump_basics

Can you provide a picture of your setup?

MAS is the goto expert on pumps, a 2-speed will always save money over a single speed, and if your electric cost more then $.40 KWH then a variable speed becomes more economical.

 

[linen]

The pump bama mentioned above would work...but I am having a hard time finding those online, so they may be out of production?

Pentair Superflo SF-N2-3/4A - A little smaller than your current pump

I agree with mas, this would be a good pump, though keep in mind it is 115V which should be fine for you if you have a neutral line available (or one you can easily pull to) where you connect the pumps electrical. Also, this pump can be a bit more difficult to find.

 

[mas985]

The MaxFlo is a little easier to find and it is a good match to what the OP has now (flow rate and voltage):

http://www.amazon.com/Hayward-SP2307X10 ... B00CG4GGE2

BTW, that comes in a VS if you are interested in that:

http://www.amazon.com/Hayward-SP2300VSP ... Max+Flo+VS

 

[Flot]

Hmm. That VSP Hayward above looks very tempting, especially with the programming features - looks like I could set it to run at 1 hour on "high" to run my cleaner, and then let it revert to my preset "low" for 8-12 hours to run the salt system. From quick reading I'd keep my existing timer to stop/start the above which helps offset some of the additional cost.

Any other comments on this pump in particular? Anything significant I might like/dislike about it before I drop $600?

 

[linen]

looks like I could set it to run at 1 hour on "high" to run my cleaner, and then let it revert to my preset "low" for 8-12 hours to run the salt system.

Wow, that seems like a long time needed for the swg (and in general to run the pump). What size pool do you have?

 

[Flot]

looks like I could set it to run at 1 hour on "high" to run my cleaner, and then let it revert to my preset "low" for 8-12 hours to run the salt system.

Wow, that seems like a long time needed for the swg (and in general to run the pump). What size pool do you have?

This is a fair criticism - I think today I'm running my pump approx 6-7 hours a day in the summer and 5-6 hours in the winter. My recollection is that I had worked it out to be somewhere around 14k gallons. The pool has stayed crystal clear for 2.5 years with almost no maintenance so I was taking the don't fix it if it ain't broke approach.

Today my water is well balanced, I'm out of tabs, and I got a good deal on the SWG, so figured I may as well make the switch this winter when conditions are more forgiving.

 

[mas985]

Quick background: S. Florida in-ground pool, 13k-15k gallons. I have a skimmer and a vac line, and two returns, each plumbed 1.5" PVC.

I agree with Linen, you shouldn't need that much run time. The T15 will add ~0.5 ppm per hour at 100%. If you need to add 1 ppm per day, that is 4 hours of run time at 50%. Even for 2 ppm per day, you can set the SWG to 100% and still run 4 hours per day.

But you might want to read this: pool-school/pump_run_time

Turnover is not all that important for run time. I have a larger pool than you and run my pump 4 hours in the summer and only 2 in the winter. About half is on low speed.

 

[Flot]

Understood on run time - some of it is purely asthetic - my concerns with efficiency etc aren't so much about cost, just that if I'm going to redo the plumbing I might as well do it the more efficient way.

My take was that with a variable speed pump and the SWG, I may as well run it very long with a low SWG cycle. I can experiment with runtime, but based on your comments I would probably do a morning and evening cycle with an hour of "cleaning" on high and then 2-3 hours of low speed operation. Looking at the amperage charts it seems like that would still cut my electric usage easily in half.

 

[linen]

My take was that with a variable speed pump and the SWG, I may as well run it very long with a low SWG cycle.

Swgs have a minimum flow rate which they will work at so ideally you would run with a flow rate just above that and only long enough to get enough chlorine in your pool, assuming your pool like most do not need as long a run time for filtering as it needs for the swg to produce enough chlorine to keep the pool sanitized. This would suggest running closer to the upper percentage on the swg would in the end allow you run the pump for the least amount of time. In your case, since the cell is quite over-sized for you pool (usually a good thing), you might be very close between filtering or chlorinating being the driving factor.

 

[Flot]

I follow you - however after stepping down my pump speed I don't see any harm in overextending my "required" runtime for the pool by an hour or two, (especially looking at some of the power ratings at low rpm) unless there's some evidence that running the SWG at a lower duty cycle would result in decreased longevity etc?

 

[linen]

No harm other than more electricity, though as you point out, not too much on low. As for the swg, the life is determined by total active run time, so lowering the percentage but running longer to get the same chlorine output does not shorten it's life in anyway.

 

[Flot]

Ok. Yesterday's project was replacing everything BUT the pump as I'll have to order that, but cleaned up some piping and got the salt system hooked up.

[attachment=0:15r3qpn0]poolpumpsnip.JPG[/attachment:15r3qpn0]

So installed a new C900 filter and salt cell, and redid the plumbing between the pump and filter while I was in there. New pump will use unions but I think I ought to be able to make that work out without too much hassle.

So I've got two 1.5" suction lines up top - one from the skimmer, one from the cleaner.

Then pump -> Filter -> T Cell - > flow switch -> reducer then a 1.5" Tee back to the returns.

I always thought the pressure gauge on my old filter was bad. However, even with this new one - the highest the pressure indicates is about 3 psi with a brand new filter. I assume this is good? Cleaner is flying across the floor and getting what I consider "normal" flow at the returns.

Although I just got everything wrapped up - anyone see anything they'd prefer to have done differently? I'll be back in it in a couple of weeks for the pump replace.

 

[mas985]

I always thought the pressure gauge on my old filter was bad. However, even with this new one - the highest the pressure indicates is about 3 psi with a brand new filter. I assume this is good? Cleaner is flying across the floor and getting what I consider "normal" flow at the returns.

Seems a little low for a single speed pump or is that with the cleaner engaged? What is the pressure with just the skimmer? Do you see any air in the pump basket?

 

[Flot]

3psi (ok, maybe 4) is as high as the pressure gets, that's with the selector valve set halfway between the skimmer and the cleaner. If I go to either full skimmer or full cleaner the pressure drops to ~2 psi.

Curiosity got the better of me and I spent 10 minutes trying to empty out a bucket. With just the cleaner hose turned on, a 5 gallon bucket emptied in somewhere between 5-6 seconds. Clearly there's a huge margin of error there, but I wanted to make sure I was getting reasonable flow. 50-60 gpm at least seems to be in the ballpark of where it should be.