RPM for Intelliflo VS #011018

[apoptosis]

Yesterday my pool pump broke. It was tripping the breaker and smoke was coming out when I forced it on. It was a Pentair Wisperflo #011775 2.5HP 230V.

Today I bought a Pentair Intelliflo VS #011018 3HP 230V. It took me all day to install it and with help of this forum and YouTube videos I was finally able to get it connected to my Aqualink 2.0 control panel.

However, now I am having problems figuring out how fast and long I should run it for daily filtration. I used to run my Wisperflo for 9 hours during the summer, I figured that would filter the water 2x and was about 50 GPM.

After reading seems like I should just be running it through 1x per day. So I want to turn over 20,000 gal 1x per day. From what I have read the energy sweet spot is at 1000 RPM for 12 hours. So right now I have it running 12hrs a day at 1100 RPM. I then run my Polaris Pool Cleaner for 2 hours during that time with 2750 RPM.

So here are my problems:

1) I can't really figure out what my new GPM is with these "Pump Performance Curves". In particular I am not sure how to get my "Total Dynamic Head in FT of Water", because I didn't build the pool.

2) My spa normally would run over "Waterfall" feature, into the pool when the pump was running. At 1100 RPM, it just drips over the edge. I don't know if this is a problem, or just an aesthetic? My worry is that calcium is going to build up there if it just drips over.

Any help would be appreciated. I feel like I am just guessing here.

 

[jblizzle]

Welcome to TFP!!!

1) Turnovers are meaningless. There is no need to worry about them, or your total head, or your GPM. A pool only needs 2-3 hours of pump run time to mix the chemistry. You may need more than that for skimming, cleaning, or chlorine generation purposes. Just run your pump long enough to keep it cleared of debris to your liking.

2) Sound like all aesthetics. Either turn up the pump output or divert more of the flow to the spa.

 

[apoptosis]

jblizzle, thanks for the quick reply. I have never heard anyone say turnover isn't necessary. Do you run the pump full blast for 2-3 hours?

Also, I am from Tucson! Went to U of A. Hear its hot right now.

 

[jblizzle]

You would not need to run the pump full blast for the 2-3 hours. The advantage of the Intelliflo is that you can run it at low speeds for very little electrical cost. Many members like to just run 24/7 at 1000rpm ... or have a few hours bumped up to a higher speed for cleaning/skimmer. But, any more than a few hours is not required for the chemistry side.

... A little warm, not as bad as Phoenix

 

[apoptosis]

So this is killing me. I get that without a GPM Gauge, I will never be able to figure out the exact turnover I want. However, waiting around for my pool to get cloudy kind of sucks too. So I tried using the Intelliflo spreadsheet that is floating around and entering in my RPM and Watts readings. I get numbers but how do I know the curve numbers are correct. Also the Head Estimate jumps around the faster the RPMs. Another thing that kills me is that I have been looking up what my filter says it needs, and they best I can tell my DE filter needs 90-120 GPM to be effective! If that is true, what is the point of running at a lower RPM at all? Why would people run at 1000 RPM 24/7? Isn't the point to filter the water? Also from reading posts it looks like maybe my backflow valves are preventing me from getting good flow at lower RPMs?

I am attaching a picture of my GPM spreadsheet.

http://imgur.com/zQtj8rC

 

[mas985]

Spreadsheet looks right to me. But then again, I wrote it so I am a little biased.

I get numbers but how do I know the curve numbers are correct.

Because they are based upon actual measurements.

Also the Head Estimate jumps around the faster the RPMs.

Head is related to RPM/GPM through the pump affinity laws. Head changes with the square of RPM. GPM is linear with RPM. Double the RPM, GPM doubles but head loss goes up by 4x.

Another thing that kills me is that I have been looking up what my filter says it needs, and they best I can tell my DE filter needs 90-120 GPM to be effective!

Not true. Specs for filters are for the maximum flow rate, not the best flow. Filters work better the lower the flow rate.

If that is true, what is the point of running at a lower RPM at all?

It's not true but the reason to lower RPM is to save on energy costs.

Why would people run at 1000 RPM 24/7?

Good question. Usually there is no need to run 24/7 unless you MUST have a spotless pool 24/7. That is the only reason to run 24/7 and not much of a reason in my mind but people still do it because with a VS it doesn't cost much.

Isn't the point to filter the water?

The primary reason to run the pump is to chlorinate the water and distribute. Once that is done, any additional run time is for aesthetics, removing surface and floor debris, or to heat the pool.

Also from reading posts it looks like maybe my backflow valves are preventing me from getting good flow at lower RPMs?

Check valves can reduce flow rate at both high and low speeds. But you can just set the RPM so that skimmers work properly were the water travels over the top of the weir door instead of around the weir doors. Then the skimmers can do their job and remove surface debris before it sinks.

 

[apoptosis]

Mark, Thank you very much. This helps a lot. And thank you for the spreadsheet, it has been my only clue as to what my GPM is.