Pump Speed and Run Time for Variable Speed Pump and Salt Chlorine Generator

[RyeRock23]

Hello! First time pool owner here so I apologize for my ignorance or assumptions up front. There are so many posts, data and opinions out there on this topic that as a first time pool owner I don't know what to believe or trust... or even how to make sense of it at this point. Equipment is in my signature. My goal of this post is to reduce electricity costs while maintaining enough run time/turnover for the salt chlorine generator. I've seen everything from run the pump 24/7 at lowest speed possible (salt chlorine generator requires minimum of 20 GPM) to running at variable speed during different times to running pump at one speed twice/day for set # of hours. Using Jandy's calculator for my pump 2000 RPM would give me 48 GPM. If I ran that twice/day in 5 hour increments for total daily run time of 10 hours it would turn pool water over twice and cost an estimated 0.34 cents/day. That seems reasonable. Although I'm uncertain how that will impact my salt cell and if that will need adjusted. Currently, the pool installer has me set at 2500 RPM 24/7 and the salt cell at 25. Pool is getting very limited to no use right now as we wait on warmer temps and these settings are keeping the chlorine around 5 at the moment.

Any insight to my situation or thoughts is greatly appreciated! Thanks in advance!

 

[Texas Splash]

Welcome to TFP! So basically know that whether you run at a a low SWG output 24/7, or at 100% output for only 4 hrs a day, it's the old say, "Six of one and half-dozen of another". Doesn't matter. Pick whichever way works best for you based on utility times, cost, prevailing winds to skim the water, etc. Just use the PoolMath APP to help you dial-in an expected FC output and you're good to go. You can adjust output and/or pump run time accordingly.

I will say that an rpm of 2,500 is a bit much. You could probably get away with an rpm of about 1,300 - 1,400. As long as the flow switch is happy, the SWG doesn't care how fast the water is going through. Hope that helps.

 

[Jimrahbe]

23,

You are just making this hard on yourself, because you have been told that you have to "turnover" your pool water X times a day. The idea that you have to turnover your water X times a day is a big myth and just not true. Chemicals (FC and CYA) keep your pool clear and sanitized, not the number of times your water passes through your filter. Your filter is there to capture all the junk that falls into your pool and floats. It is not there to capture algae. By the time your filter sees any algae, you have already lost the algae war.

We believe that you should run your pump for a reason, not some myth. The two main reasons are to generate the amount of chlorine your pool needs, if you have a chlorine tab feeder or a SWCG, and to skim the surface of your water.

Normally, if you run the pump long enough for the SWCG to generate the chlorine your pool needs, you will also have run it long enough to skim your pool.

You can run your pump anyway you want. We do not care if you have 100 turnovers a day, or .1 turnovers per day. Our goal is just to let you know that X turnovers a day is not a requirement to have a well-managed pool.

I personally run my IntelliFlo pump 24/7 at about 1200 RPM, most of the time. I do this because I like to make a little chlorine all the time and to skim all the time. I run my pump for a reason, and not to try a satisfy some myth. The cost for me to do this is less than $20 bucks a month.

Thanks,

Jim R.

 

[RyeRock23]

Decided to run at 1250 RPM 24/7 (started Wed. afternoon). By Thursday morning I noticed quite a few very large air bubbles through the pump basket lid. Set RPM to 3000 which cleared bubbles, bled them from the filter and resumed 1250. 6 hours later bubbles forming again. Removed pump basket lid and reseated to be sure no air leaks there. Out of curiosity ran at 2000 RPM for several hours. Still getting bubbles, but they are smaller. Pool installer stopped by this afternoon and says it's common to get air at such low RPM and I should keep it above 2000. Obviously, I'm brand new to all of this, but I don't think I agree with his assessment. My opinion is that there may have always been air getting in there, but it's less obvious at the higher RPM because it moves the air out of the basket much more effectively than the lower RPM. The lower flow (1250) keeps the water moving, but isn't strong enough to blow the air out of the basket. My pump is way oversized for my pool and still getting good flow at 1250RPM so I would say there is a suction side problem. His suggestion is to leave the RPM around 2700 24/7 and it will provide all around benefits. Unfortunately, his solution is $1.70 more per day than me wanting to run it at 1250 (per Jandy's calculator for my pump). Feeling stuck at the moment because I don't want to burn up the pump with air...

Am I correct that there should not be any air infiltration regardless of the RPM?

 

[1poolman1]

Thirty-four cents a day, +/- $10.00 a month, is a very small price to pay to have a clean pool. Compare that with what it would cost to get your water clear again, not counting your labor, and you would be willing to pay twice that, happily.

 

[Jimrahbe]

23,

Just set a schedule that ramps the pump speed up once or twice a day for half an hour, and run at a lower RPM the other 23 hours a day.

It does not matter if there are bubbles under the pump lid as long as they don't keep getting bigger and bigger. As long as the water stays above the basket, your pump will work just fine.

You can never go too big with a VS pump.

Thanks,

Jim R.

 

[proavia]

In addition to the great advise already provided - you may want to removed the pump basket lid, clean the o-ring and its mating surfaces and relube the o-ring with silicone pool lube. This should help keep the air bubbles to a minimum at lower rpms.

 

[Bvill16]

Decided to run at 1250 RPM 24/7 (started Wed. afternoon). By Thursday morning I noticed quite a few very large air bubbles through the pump basket lid. Set RPM to 3000 which cleared bubbles, bled them from the filter and resumed 1250. 6 hours later bubbles forming again. Removed pump basket lid and reseated to be sure no air leaks there. Out of curiosity ran at 2000 RPM for several hours. Still getting bubbles, but they are smaller. Pool installer stopped by this afternoon and says it's common to get air at such low RPM and I should keep it above 2000. Obviously, I'm brand new to all of this, but I don't think I agree with his assessment. My opinion is that there may have always been air getting in there, but it's less obvious at the higher RPM because it moves the air out of the basket much more effectively than the lower RPM. The lower flow (1250) keeps the water moving, but isn't strong enough to blow the air out of the basket. My pump is way oversized for my pool and still getting good flow at 1250RPM so I would say there is a suction side problem. His suggestion is to leave the RPM around 2700 24/7 and it will provide all around benefits. Unfortunately, his solution is $1.70 more per day than me wanting to run it at 1250 (per Jandy's calculator for my pump). Feeling stuck at the moment because I don't want to burn up the pump with air...

Am I correct that there should not be any air infiltration regardless of the RPM?

I am having this same exact problem. I bought a Vsp in hopes of running it at low rpms for most of the time but now I’m a bit deflated that it may be getting air inside and eventually seize my pump if I don’t check it every so often. I am at a loss here.

 

[Bvill16]

23,

Just set a schedule that ramps the pump speed up once or twice a day for half an hour, and run at a lower RPM the other 23 hours a day.

It does not matter if there are bubbles under the pump lid as long as they don't keep getting bigger and bigger. As long as the water stays above the basket, your pump will work just fine.

You can never go too big with a VS pump.

Thanks,

Jim R.

Wow I didn’t realize bubbles were ‘ok’. I was trying to get perfection (my ocd personality). I may take you up on this suggestion as a solution for my low rpm/bubble issue.

 

[RyeRock23]

23,

Just set a schedule that ramps the pump speed up once or twice a day for half an hour, and run at a lower RPM the other 23 hours a day.

It does not matter if there are bubbles under the pump lid as long as they don't keep getting bigger and bigger. As long as the water stays above the basket, your pump will work just fine.

You can never go too big with a VS pump.

Thanks,

Jim R.

This is a great idea. However, I tried this solution as my Jandy controller has the option to set two separate speeds/timers. Both schedules say enabled. One is to run 11a-1059a at 1250RPM and the second to run 3000RPM 10p-1030p. Manual says when two programs overlap the higher RPM takes priority and runs. Once the higher RPM program ends, if the original program schedule is still in effect it will resume. Neither schedule will run at all

 

[BMerrill]

Maintaining 5-7 ppm FC
Current schedule for VSP: ON @7:56am OFF @ 1:01PM running at 1518 RPM for a flow rate of 55 gal/min uses 230 watts. Primes at 3000 rpm for 2 minutes.
SWG 50% output ON at 8am off at 1pm

 

[RyeRock23]

What is the longest period of time that you should go between pump end time and pump start? After much thought I've decided to run at higher RPM for less hours of the day. I'm debating to either run 6 hours on (10a-4p), 6 hours off (4p-10p), 6 hours on (10p-4a) and 6 hours off (4a-10a) OR just run 12 hours on (10a-10p) and 12 hours off (10p-10a). My thoughts are, the less start/stops the better for the pump motor. However, I worry if 12 hours between run times is too long without some circulation/filtration? Thoughts?

 

[Darin]

If you are set on turning it off, check you electrical rates and turn it off during "Peak" cost hours. I just run mine slow 24/7.

 

[RyeRock23]

If you are set on turning it off, check you electrical rates and turn it off during "Peak" cost hours. I just run mine slow 24/7.

Thank you for your reply. Yeah it goes up 4 cents from 4p - 8p so I've thought about avoiding that. However, at just 16 cents/day, a swimming season of about 5 months and 4-8 being peak sun/heat/swimming/cover off time I'm not sure it makes much sense to shut it down for such little savings. I love saving money, 2500 RPM for 12 hours = $0.77 and 1250 RPM for 23.5 hours/2750 RPM for 0.5 hours (clear air from pump basket) = $0.30. About $70 for the season. The water movement at 1250 RPM is very underwhelming... Getting way off topic here, but I'm perplexed why my pool installer placed all 3 of our return jets in the shallow end over the sun deck. We've pointed all three to run the water counter clockwise in effort to move water effectively. I would have thought there would be at least one return jet in the deep end to help with complete pool circulation. Using a clock as an example, if the skimmer is 12 then the jets are at 3, 4 and 5. I've put a floating thermometer at 7 and it rarely makes a trip around the pool. Most of the time it sits between 6 and 9.

Sorry for getting so off topic there. Bottom line for me right now is trying to figure out if my assumption that less start/stops by the pump = longer pump life is correct and if so, is there any concern letting it go 12 hours without running. Schedule would be 10a-10p on and 10p-10a off.