New Pump Needed

[ryanadidas]

Greetings folks!
Long time lurker, first time poster.

I have a ~20,000 gallon in-ground pool. For years, I have been using a free-to-me 1.5HP Hayward Power Flow LX (SPX1580x15) pump and a small sand filter to circulate my water. I have decided to upgrade my filter and pump because my current set-up isn't moving enough water. The pump was previously used in a very small (maybe 10'x10'x4') pool, so it may have a smaller impeller installed. Either way, the pump is ~15 years old and I am tired of messing with it...

I was considering getting a new variable speed pump, but my electric rate for off-peak usage is only 4.7 cent per KWH. I don't think that I can justify spending the extra money since my power is dirt-cheap 20 hours out of the day.

I have already installed my new sand filter. It is a Hayward S224T.

SETUP: My floor drain goes into my strainer basket, which is a single 2" inlet to the pump (currently necked down to 1.5"). I have two 1.5" return lines to the pool. One splits to two jets and the other return is for my Polaris 360. No heaters, no SWG (at this time).

I am trying to decide between a two 1.5HP Hayward pumps, the Super Pump II and the Tri-star. I am open to buying a two-speed pump, but with my power being so cheap, I am tempted to go all Tim "the Tool Man" Taylor and throw a big-bad single speed pump that will move some serious water.

Any suggestions?

Thanks in advance,
Ryan

 

[zea3]

Hi, welcome to TFP! Water actually filters better when it moves slower. You don't want to buy something so powerful that it blasts the water through the filter and nothing gets caught in the sand! Look for a 2 speed pump if you want a little versatility. Run it on low for filtering and water circulation and move it to high for vacuuming.

How does your water look now?

 

[ryanadidas]

I don't have the numbers in front of me, but the chemistry is good. FC, pH, TA, CYA, CH are all within range.
I have quite a bit of sand and/or small debris in the bottom that I can't get out because my pump doesn't have enough power to propel my Polaris 360. I have been trying to manually keep it "stirred up" and let the sand filter do its job, but that is a slow process.

 

[JVTrain]

You can still get a big bad ARR ARR ARR ARR pump but in a 2 speed version it will have an Oooo Oooo Oooo mode that will filter better and save you cash when not vacuuming/cleaning. Just think of it as a beefy motor with a transmission upgrade! Not much cost increase vs. single speed either.

 

[ryanadidas]

I used gauges on my existing pump and measured 8inHg suction and 15psi at the pump discharge. I calculated a TDH of 45ft. These measurements were with all filters and strainers perfectly clean: and ideal situation.
My sand filter is rated for 63GPM.
If my pool is roughly 20,000 gallons, it would take 28GPM minimum to turn the pool volume over in 12hrs.

I am leaning towards a Hayward Super II 1.5HP single speed (model SP3010X15AZ). At 40' of head, it is rated at 90GPM and at 50' of head it is rated at 78'. This is more than my sand filter is rated at, but I want to allow for extra capacity in the event of a partially clogged strainer, etc.

The two-speed version of this pump is only rated for 14GPM at 20' of head, so I am assuming that at 45' of head, it would be ineffective. Am I understanding this correctly?

I found the single speed version for $420 here: http://www.poolsuppliessuperstore.c...e=&network=g&gclid=CMCy0Nm_88wCFQgxaQod3YYM5A.
Does anybody have any other recommendations for me?

 

[RobbieH]

Watch out, you don't want your pump pushing TOO hard when something is clogged. You can cause damage to the plumbing.