Trying to determine GPM on my EcoStar SP3400VSP

[james_95]

I am trying to get my pool pump setup with the goal of balancing the run time, with energy savings, with water turn and in order to do this I need to know the GPM at any given RPM. It doesn’t have to be spot on accurate, just an estimate would be good to get me started.
Here is my setup:
Hayward SP3400VSP EcoStar pump
Hayward Pro-Grid DE Filter (48)
19,000 gal of water
AutoPilot Salt system
1.5” pipe everywhere
10 solar panels on my 1 story roof
Pump it about 20’ from the pool and about 45’ from the side of my house where to solar panels start
There is no spa, no water features, no heater…just a basic pump, filter, solar setup

I’d like to turn the pool 1-1.25 times in 12 hours. I’m in SoCal and want to take advantage of the sun/solar during the prime time of the day so I want to turn about 14K gal from 10:30am – 5:30pm and turn the remaining 5k-10k in the morning and the later evening.

Here are the stats I currently know: (the PSI is referring to a pressure gauge that sits on top of my DE filter) this is also running everything through my solar panels which is 80% of the year.

RPM – 1000 Watts – 69 PSI 0
RPM – 1725 Watts – 195 PSI 6
RPM – 2500 Watts – 580 PSI 14
RPM – 3250 Watts – 1260 PSI 25

Anything you can do to help me determine estimated GPM would be GREATLY appreciated.

Thanks,
James

 

[linen]

Flow rate is very plumbing specific, so it can be a involved process to predict. To get a rough idea, you could run your return water into 5 gallon buckets and time it...of course by just doing that you will be effecting the flow rate a little, so that approach is not really accurate.

Good news is, knowing the flow rate (gpm) isn't really necessary and doesn't really help when it comes to keeping a pool clear. More importantly is to run "long enough" which is ofter a much short time then 1 turnover. See this pool school article: http://www.troublefreepool.com/pool-school/pump_run_time

 

[james_95]

Thanks for the insight, that'll help me with my set for sure. I'd still like to know the GPM though if anyone has the answer...just to know :-D

Thanks,
James

 

[mas985]

I have a couple of spreadsheets you can use to estimate GPM (see signature) but your numbers do not make any sense. The wattage is much too low for the RPM values. If correct, your plumbing would have a huge amount of head loss. Typical numbers for 1.5" plumbing should be:

3450 RPM; 2005 Watts; 71 GPM
1000 RPM; 88 Watts; 22 GPM

 

[james_95]

Thanks Mark for looking into it. I figured if there's one guy that'd have the answer it'd be you.

I'm pretty sure about the numbers although I'll triple check tonight. Is it possible that the 10 solar panels are causing the head loss? although it's only a 1 story house the roof has a "step" in it and it's "T" shaped so there's more plumbing than just having them all laid out next to each other.

I will say that when the pump is running at 1725 RPM the water seems to be flowing very slow from the return jets compared to my old 1-speed pump that water was blasting from.

any help would be greatly appreciated.
James