Another reason that variables or even two speed pumps may not realize the cost savings that is often advertised is that sometimes you just need higher flow rates and sometimes fairly often. It would be nice if you could operate a pool at 20-30 GPM all the time but in many cases, that is just not practical.

Pools with elevated solar installations, vacuum/pressure cleaners, and even skimmers do not operate very well and sometimes not at all when the flow rate gets too low. Not to mention water features and/or a spa. So you can design a pool to be ultra-efficient but in the end it may not matter that much if you are running the pump at higher speeds most of the time.

I'm not sure what your saying is true because you are mixing up a number of variables.

The savings in a pump like the Intelliflo come from at least two places.

1) Since it is variable speed you can set the flow to exactly what you need it to be. That is difficult to do otherwise. Even if you need a higher flow rate the ability to pump only as much as you need is going to save energy.

2) The intelliflo uses an ECM motor. This motor is more efficient that the motor used in single and two speed pumps. How much more efficient is a difficult question to answer because I've yet to see other manufacturers publish or be willing to provide pump curves with power consumption data. Since whole system energy consumption is a function not only of the motor but the pump design one can't just look up the motor information and go from that.

That said are you sure solar needs much more than 30-40 gpm? That kind of surprises me. I've got the specs of the Polaris pressure cleaners and they don't require much flow at all. In fact their top of the line 380 needs about 15 gpm. As for skimmers, there is no reason to run them at all really when a cover is closed because the surface friction essentially renders them inoperable so anyone with one of those can run quite slow all night and whenever else the pool isn't in use.

So I'd say it is quite practical to run these kind of flows. I'm not sure the components you refer to require very high rates and even if they do they don't run all night (no sun, way more cleaning that is required of a robot, no water feature) and even at 40 gpm an ECM motor equipped pump will consume less power than a one or two speed.

The downside is they cost more, but you can save the cost of a boost pump (plus the energy consumption of running two pumps during cleaning) so the payback is quite quick, IF you set the system up right.

But I agree if you just swap out a single speed pump running at say 60 gpm for an Intelliflo and set it to run at 60 gpm the savings aren't going to be very big.

Roughly 60 GPM @ 20 feet of head is about 500 watts and 40 feet is 750 with and Intelliflow. A 3/4 HP is about 1200 watts. Still quite a savings.

Scott

For solar, it isn't always about flow rate although sometimes it is. Most manufactures suggest at least 1 GPM per sq-ft of panel. In my case, that is about 48 GPM.

Also, sometimes it is about pressure. With a solar installation 25 ft. in the air, the pressure drops from the filter to the vacuum release is about 11 PSI for elevation alone and another couple PSI for dynamic head loss. So if there is a vacuum release valve at the top of the panels, then you need to have enough pressure to keep it closed. Low flow rates generally will not do this unless you restrict the returns which is counter productive. In fact, in my case, I need about 50 GPM to keep the filter pressure at 16 PSI so there is positive pressure at the VR (+2 PSI). Which works out well for the solar efficiency.

Could you design a solar setup to make it work? Yes, but in ny case it wouldn't matter much since I want the flow rate close to 50 GPM for solar efficiency anyway. But one could lower the VR such that it doesn't require as much pressure to remain closed.

Also, 30 GPM may be enough to run a cleaner OR a skimmer alone but probably not both at least not effectively. Low speed on my pump is about 30 GPM and I find I would need to isolate the cleaner to get to work properly and shut off most of the skimmer. Also, I find that skimming does not work as well at 30 GPM even without the cleaner running. Instead, I prefer to run at high speed to get some fast effective cleaning while having the skimmers work better as well. Generally, I reserve low speed for just filtering.

I wasn't suggesting that the Intelliflo doesn't save money or energy, it does and at nearly all speeds. I was only suggesting that sometimes you won't get the savings that they advertise which assumes running at the most efficient RPM ALL the time. If you have to run the pump at higher speeds for a good percentage of the time, the savings will be less but still better than the single speed pump.

I have read several posts on different forums of users that expected a lot more out of their Intelliflo. After installation, they found that the lower flow rates didn't work so well for a variety of reasons which is why they ended up using higher speeds for at least part of the run cycle. I just think that people should be aware that could be a possibility.

I just noticed a typo above, I meant 1 GPM per 10 sq-ft panel.

Quote: "I'm really interested if you only use the cleaning and filtering modes. If you are running a IntelliFlo (especially the VF model), please post whether you really experienced payback within 2 years."

Mostly on this forum we get people who are putting in new pools, so you may not get a specific answer to that here. You might try www.troublefreepool.com/ , they get a lot more remodel discussions over there than we get here.

As for my personal experience with the IntelliFlo, we were surprised at how little our electric bill was affected by our pool. Our pump runs on low speed for filtering (for 10 hours a day), then ramps up to a moderate speed for cleaning (in conjunction with a booster pump, runs for 45 minutes a day). It's only on high speed when we're swimming and running the grotto and slide. We checked our electric bills before and after, and it appears we're spending 30 to 35 bucks extra a month for running the pool. I don't know how that would compare to a single speed pump, but it does seem pretty efficient in our application.

Since my installation doesn't include solar I can't really respond to the issues you raise except to ask if an installation was designed from scratch with minimum energy consumption in mind could things have been engineered differently? If you look at the Intelliflo pump curves you will see that they flatten out substantially at low head. There probably isn't a lot you can do about the elevation change (except to try and minimize if there is an option) but what about everything else?

My experience has been that most pools aren't even engineered, let alone well engineered. Head losses are at best estimated, rarely is there a real system design with each component accounted for let alone a cost/benefit analysis. Pumps are chosen for worst case maximum flow and then its plug in and let 'er rip.

But I digress.

As for losses, I assume you aren't running the solar at night so even during the summer there must be 8-12 hours when the head loss is substantially less than you quote.

Also while you might not have venturi skimmers, a new installation could and those only require 8 gpm each. Add the 15 gpm for the cleaner and its still only 30-35 gpm with both cleaner and skimmer running and 16 gpm for skimmers alone.

Assuming you can keep the back pressure way down though appropriate piping, a properly sized filter and low head MPV (all of which are cheap to do in a new installation) the system should be able to perform well.

As for overall energy consumption I don't doubt it is still a small percentage of your entire residence. If its hot and you're using substantial air conditioning that energy use is going to dominate and if its cooler heating the pool will. That doesn't mean it isn't worth making the effort. As I've noted previously the right way to approach the problem is as a whole. Look at every part of the house and ask if you had $1 (or think of it as $1000) to spend what saves the most energy? Do that first, then whatever is next on the list and so on. Its a very simple algorihm but its rarely done, probably because neither the customer nor the contractor knows how.

sbedelman,

Again, I don't disagree with anything you have been saying. As you clearly point out, a pool can certainly be designed with all of these things in mind and do much better. But for the pool owners that have an older pool with smaller plumbing or maybe solar or only one return or something else that limits the time they can run at low speed, they probably won't get the same savings as someone who just had their pool built and optimized for an Intelliflo. In fact, most new pools built today still aren't designed this way.

The OP asked if the results were as expected. This depends on one's expectations. If you think you will save as much money as what Pentair or anyone else tells you, you could be disappointed. Each pool will have different savings depending on what pump they are using now and how they will be using the new pump in the future. There are a lot variables and each owners results will be different.

However, I see many pool owners expecting to be able to run their new pump at the most efficient setting all the time to get maximum savings. For most pools, I believe that this is an unrealistic expectation.

I don't think we disagree. I did not interpret the OP as asking only how users of existing pools fared.

From least to most here how I think it would pan out if

1) Poorly designed pool with lots of head loss. Existing pump is replaced by Intelliflow with no other action taken.

2) As above but flow is significantly reduced wherever possible

3) Well designed pool, low head loss, traditional skimmers. Existing pump is replaced with no other action taken.

4) As above but flow reduced wherever possible.

5) Exceptionally low head loss pool with reduced flow and careful attention to minimum flows.

6) As above but with minimum use of power hungry option such as water features etc

7) As above but with the addition of venturi skimmers

If you make it all the way to #7 there should be no problem running the pump at a very efficient setting most of the time. The run time for the cleaner and heater should be relatively short and in any event should only require around 40 gpm.

In summary a well design pool system will result in the most savings while a poorly designed one will see the least. Pool owners should get the saving they expect IF they perform a calculation for how they intend to run the pump before they purchase it. This is equally true for a new pool as a retrofit.

Of course if a vendor makes a broad brush promise of savings without the specifics of the installation its is likely the answer will be wrong.

Do we agree or am I still off base?

For the most part I agree, but from my experience, most pool owners do not do the calculations and tend to just go to the Pentair web site for the simplistic answer and/or listen to their PB that probably doesn't do the calculations either. So they end up with fairly high expectations on power savings and often times see posts were they had expected to run their pump at the lowest speeds all the time but found they needed to run at higher speeds for a variety of reasons.

Good discussion guys....

Pipe velocity is the key....the lower the better.

2 ways to achieve this: 1) big plumbing (3" minimum) or 2) small pumps (1/3 HP typical)

Big plumbing for a new pool will pay dividends everytime the pump is turned on. This is by far the best ROI (return on investment) due to low PVC pipe cost and life span of the pipe.

For those homeowners with smaller pipe on existing pools, the only option is to go with small HP pumps to reduce flow. 2 speed pumps deliver about 1/3 HP at low speed which results in significant reduction in pipe velocity and friction loss with significant power savings.

Variable speeds can go lower than 1/3 HP and also have the advantage of being an additional 200-400 watts more efficient at the lower speeds. This 200-400 watt gain (2-4 100w light bulbs) comes at the heavy expense of technology cost which decreases the ROI for the variable speed equipment when compared to 2 speed.

Higher speeds are always necessary..some pools more than others. Variable speed pumps typically use more power than 2 speed pumps at these higher speeds. Although it appears Jandy and Hayward variable speeds have the same efficiency as their 1 speed counterparts at higher speed. This may be due to their design philosophy of having different size variable speed pumps and not having a "one size fits all" pump like the Pentair.

Bottom line...pipe velocity is the single biggest contributor to reducing power consumption to save energy. Plumbing power robbers such as sharp 90's, tees, valves, fittings, etc. are insignificant when the pipe velocity is small. The bigger the pipe, the lower the pipe velocity and you get the added benefit of having larger tees, 90's, fitting, etc which have lower losses inherently. For those with existing pools, go with a smaller pump to do a majority of your circulating and filtering needs with low pipe velocities on existing plumbing. A 2 speed or variable speed will get you into the small HP pump size that you need to save energy.

Piping also lasts the lifetime of the pool making the decision to upsize a no-brainer. Pumps will need replaced so replacement costs should be considered heavily when making a decision on type of pump. For this reason, I'm a big fan of 2 speed pumps which can be serviced for a relativley small cost when compared with their variable speed counterparts.

Hope this helps!

I agree with trhought that larger pipes have a good roi. I don't believe they are the single biggest contributor to power consumption (although it isn't clear he meant to say that) unless they were substantially undersized to begin with. To be more specific, filter losses, especially MPV losses are often a significant portion of total loss. But this isn't really the point. As I said the correct methodology is to spend the money where it gets you the most bang for the buck.

Using that as a guide then piping of 2.5" for short runs, 3" for longer ones is about right, but not a minimum as suggested, unless one is planning on flows significantly greater than 50 gpm for most of the operating time which really shouldn't be necessary in a residential pool unless one had significant water features.

The next big bang for your buck is a low heat filter and mpv. Depending on your system topology this might have an even greater effect on energy consumption than upsizing the piping.

Trhought and I disagree regarding the energy consumption of more tradition pumps including 2 stage vs the Intelliflo only because I know what the latter uses because Pentair publishes power graphs and I have yet to see them for any of the former. In the absence of this information I think he is reaching in stating the known performance because the numbers just aren't out there.

As soon as they are available, then we will know. He might be right, but until I see engineering data I don't think it is correct to assume.

Ok, so I have a question now. If I am building a new pool (40k gal), and have specified a Jandy variable speed pump, what size pipe should the pb be installing?

You need to take a couple of minute with Google and educate yourself on how to do a calculation for piping head loss. Either than our you should have your PB do it for you.

You start with how long the runs are, add it the turns, then using the flow rate you expect (which you also need to calculate), determine how fast the water will flow in the pipe for each pipe diameter. Alternately I can give you a number, but it has the risk of being either oversized or undersized because the only way to get it right is to know the characteristics of your system.

With that in caveat in mind, here is your answer. 3" or the equivalent in double run pipes (two or more in parallel) is generally sufficient.

But again, be warned, this is the wrong way to do it. Just have someone do the loss calculations. It can't take more than 30 minutes tops to do the whole system. Then you will get the right answer.

A comparison of pump energy consumption can be found at the California Energy Commision's web site:

http://www.appliances.energy.ca.gov/AdvancedSearch.aspx

The data contains two curves A & B and soon curve C which represents different types of plumbing. B is the worst, A is better and C will be more typical of a well designed plumbing system.

Also, I took that data and put it into a simple spreadsheet which allows someone to compare the operational costs between pumps:

http://www.troublefreepool.com/pool-pump-energy-cost-comparison-t18378.html

Curve C is extrapolated from A and B until the CEC publishes the data. If you use the spreadsheet, make sure you read through the post as there are some errors in the CEC data.

angiedfw....I would ask the PB to do minimum 3" piping for the filter pump. You will likely get some pushback from the PB with some comment like "we've been doing pools for over 30 years and have always done it this way". I know that's what my PB said.

Keep pushing them though. Another option is to specify Jandy's versa-plumb system. I mention this only because it sounds like your PB sells Jandy equipment. This is a nice system they put together recently that is pre-engineered to provide low loss piping, valves, fittings, etc. for your circulation system to save lots of energy.

I wish they would have had this system when we built our pool a few years ago. It would have saved a lot of headaches along the way...both with the PB and all the homework that went into designing our piping.

The Jandy VS pump also has 3" couplings so you will not have to reduce the 3" plumbing down to 2.5" like you have to do with the Intelliflo.

Hope this helps!

mas985...thanks for providing the pump comparison data again. I had lost the link but had the excel spreadsheet saved on my computer from last fall when you posted the data.

sb...this is the data I was referring to.

Hope this helps!

Maybe I'm just being thick but I don't see any pump curves. This is what I think of when I think of pump curve. See page 47.

http://www.pentairpool.com/pdfs/IntelliFloOm.pdf

Unless I'm missing something there is nothing here that will let me determine power consumption for any given flow and head. Without that its all just talk.

This is not a complicated issue. The only reason we don't have a definitive answer is that the pump manufacturers don't publish the data. California has run tests at a few discrete points, put until one has fully characterized a pump and published a set of curves there is no way to know what the pump is doing under all relevant conditions.

I know you like to tout two speed pumps as being better and I'm happy to buy it as soon as I can put the data side by side. Until then it remains nothing more than speculation.

That said, if you believe I'm wrong can you tell me what the power consumption is for your favorite pump at a few test points where we know the power consumption of the Intelliflo?

How about the following two...

28' head, 60 gpm, 700 watts
90' head, 60 gpm, 2100 watts

Both of these are flows much higher than I'd design a pool to run on a daily basis and the latter is all the way at the upper range of the pump so I would expect that if there is anywhere that a non ECM pump should compare favorably it would be here.

Alternately here is where I'd thing the Intelliflo should be at an strong advantage

33' head, 40 gpm, 550 watts
5' head, 30 gpm, 100 watts

Obviously what is missing are some additional curves between what is published. I ran some numbers when the van visited to fill in the gaps and will see if I can find them, but in the meantime if you can tell me how these stack up against the best of breed of the pumps you favor it would be a good start.

Again, its not that I have anything against one or two speed pumps. Quite the reverse if one can design to a pump without having to run harder than is required and if that pump uses the same power its great. The problem is I don't see that its all that likely things will match up so you will probably have to upsize which would mean using more power. And it has yet to be shown that these pumps use the same power and any given flow and back pressure as you assert.

One more thought. Since the pumps you are talking about only have one or two curves if they don't happen to line up with what Intelliflo has published it would be quite easy to rerun the curve for their pump using the same flow rate and head that you have already characterized. I have no idea when they will next roll through my neck of the wood but when they do I'd love to run that test.

All I need is published curves on the pump you want me to compare to. So far those don't exist however and frankly I don't think that is an accident. But if you can find them or create them it would be wonderful.

But we need a real curve.

What I think you are looking for is a set of 305 pump curves, one for each possible speed of a VS-3050.

Scott

sb...having pump curves from each manufacturer would make for an interesting academic exercise but I'm skeptical of the outcome since the curves are published by the manufacturer's with no oversight (I think you will agree on this). In my opinion, this exercise is old school now that the California Energy Commission has published comparison data using a standardized test. I'm curious why you dismiss the data published by the CEC so easily. Granted, it does not support your conclusions regarding pump performance comparisons but it is real data from a third party.

For me, it was enlightening to see data comparing different pump manufactures and technologies used by each. When I started to research pump performance a few years ago when building our pool, it was frustrating to find the pool industry had no standards by which to compare technologies or measure performance. I was relegated to comparing pump curves from various manufacturer's and all the assumptions and good faith associated with that exercise.

What the CEC has done to create a standardized test for the comparisons and publish a common metric for easy comparison seems logical to me. Having the standardized test completed by a third party validates the test results without bias one would think. As an engineer and consumer, the CEC published data seems the most reliable source so far for comparing pump performace in real-world conditions . Hopefully this body of work also marks the first step towards standards that will be embraced and updated from experts in the pool industry as time goes on.

Regarding pump efficiency, there's no doubt VS technology is marginally more efficient at the lower power levels as I indicated above and in previous posts; 2 - 4 100w light bulbs difference compared to 2 speed. There is however differences at higher speeds and some VS technology does better than other VS technologies. Knowing a little about VS technology over my career, this is likely due to different design philosophies by the manufacturer's. One seems to have taken a "one size fits all" philosophy, while others chose to have unique drive/motor/wet end combinations to deliver better efficiency over a broader range.

I'm still a big fan of 2 speeds due to price, simplicity, serviceability and quiet, efficient operation, but to each his own.

Just my opinion though.

i have a question about the "curves" in the piping to get reduce friction/get maximum efficiency. We are installing a new pool with the IntelliFlo pump; there are clear right angle turns in many places - in the pool and outside. Should these be "curves" instead? If so, does someone have a drawing of what this should look like?

The CEC measurements are done for specific plumbing curves. When they do the tests, they set the pump flow rate and head so that it intersects the plumbing curves. So each measurement represents an single operating point on both the pump head curve and the plumbing curve with a GPM, Head and Watt value. So the way to use the CEC data is to directly compare the Gallons/Watt-hr column for the same plumbing curve. This is listed in column k or column n depending on which plumbing curve you want to look at.

Using standard plumbing curves is a better way to compare pumps than by comparing head curves because it represents pump performance on exactly the same plumbing system. More of an apples to apples comparison. Plus most people don't know what their own plumbing curves are so the CEC felt if they just gave a couple of representative values, that people could make a more informed choice. However, the CEC recognized that their plumbing curves were somewhat pessimistic so they are generation a third curve (C) to represent more efficient plumbing. Each plumbing curve is defined as:

Plumbing Curve A Head = 0.167 * GPM ^ 2
Plumbing Curve B Head = 0.05 * GPM ^ 2
Plumbing Curve C Head = 0.0082 * GPM ^ 2

Each of these plumbing curves interesects each of the pump's head curves at a single point.

The CEC data is perhaps the only and certainly the most comprehensive energy consumption data available for residential pools pumps.

So what I have done is to use this data in a economic analysis that I posted in the TFP site. You have a choice of three plumbing curves A, B & C which is extrapolated from A & B using theoretical pump equations. So the spreadsheet allows you to choose a plumbing system and compare the energy consumption of multiple pump on the same plumbing.

Currently, I have set up two default scenarios. #1 is using the average US energy cost of $0.12/kwh, #2 doubles that cost.

The other inputs are listed on the TFP post but if you have any questions about how to use the spreadsheet, let me know.

So if you look at the default scenario 1 in my spreadsheet;

Single Speed WFE-28, 82.5 GPM @ 55.8' head & 1939 watts
Two Speed WFDS-24, high speed, 76.8 GPM @ 48.4' of head & 1602 watts.
Two Speed WFDS-24, low speed, 44.4 GPM @ 16.2' of head & 363 watts.
Intelliflo, 2794 RPM, 76.8 GPM @ 48.4' of head & 1433 watts
Intelliflo, 1000 RPM, 30.39 GPM @ 7.6' of head & 139 watts

For each of these, I assume 0.25 turnovers per day at higher speeds and 0.75 turnovers per day at lower speeds.

In scenario #1 case, the two speed has a better NPV because the cost of the pump is less and the $/kwh is low. So even though the Intelliflo uses less energy, the savings is not as great because the initial costs are more.

However, if you look over scenario #2, the opposite is true because the $/kwh is higher so the savings makes up for the intial cost.

But the outcome of the analyis varies quite a bit depending on the assumptions.

Here is a link that might be useful: Pump Energy Cost Comparison Link

Allen we.below is a link to pictures showing what sweep 90 degree fittings look like in an engineered plumbing design. This is the ideal way to plumb 90 degree turns to maximize hydraulic efficiency. As I stated a few posts above, if your plumbing is large diameter, the sharp 90Âs will not have a large impact on hydraulic efficiency at low flow rates due to low pipe velocities. When running the Intelliflo at higher speeds the sharp 90Âs will reduce efficiency of your system. Bottom line, only run at higher speeds when absolutely necessary. The Intelliflo and your plumbing with sharp 90Âs will offer respectable system performance at low speeds but not at high speeds.

Mas985Âgreat spreadsheet and a handy tool for those who want to run some numbers to help with their decision on pump selection for their needs. YouÂre correctÂthe outcome of the analysis does vary greatly depending on assumptions. From your example above, running the Intelliflo at 30 gpm is marginal in my opinion to satisfy low flow requirements for other devices in the circulation system. A flow closer to 40 gpm is probably more practical. At the 40 gpm flow rate, the Intelliflo is not much better than the 2 speed at 44 gpm . This will have a significant impact on NPV calculations, both at $.12/kwh and $.24/kwh rates....correct?

I used 1000 RPM for the Intelliflo specifically because it is usually the most energy efficient RPM setting. This was a bit unfair to the two speed pump but then again the two speed doesn't have the flexibility of the Intelliflo so it is disadvantaged. I assumed the same flow rate at high speed as that might be used for a specific purpose.

So yes, if you use 40 GPM (1333 RPM), the energy efficiency will drop some and energy use goes up by about 100 watts but NPV would change by only 8%/13%. You can change the relative speed of the low speed to 133% to see the difference.

mas895 answered the question of why I think pump curves are the important. They are the only way to evaluate how much energy the pump will use under a given set of conditions.

The tests you like are similar to the stickers the government mandates for windows and appliances. As mas985 says they are a simplified set of data for a general public to compare based on. The advantage is its simple, the disadvantage is that the data often lead to wrong conclusions because of the assumptions they make (the window or appliance isn't used under the conditions they tested under).

Same with pumps. As I've stated it depends on the design. If I had a pump curve on a single speed pump and it was possible to design a system that ran right at that pumps most efficient point, then the proper engineering method would be to compare the pump right there to the alternative. I'm happy to do that as soon as I get the pump curves and then we will all know how it stacks up (in this case it would be best case for the single speed).

We've been over this ground before and frankly its getting old. The only pump performance that matters is how it acts in the system. Not in some different get up that the State uses. This should be obvious, not just to engineers. Comparing the pump performance under any conditions other than the one it is actually used at is not only bad engineering, its just dumb.

So as my final comment before signing off and for those who truly care about getting the right answer I suggest the following. Start with a good design. Once you know what the flow rates and head are for your pool, look at the pump curves (demand them from any potential supplier).

Compare the energy consumption of a one speed, two speed and multispeed. It is likely that your design won't exactly match with the first two, but get as close as you can (which shouldn't be hard to do). Compare the energy consumption and do a payback analysis. Based on this you know the answer.

Its just that simple. Anyone who is trys to make it harder than this is just trying to do so in order to distract from getting the hard data you need to get the right answer.

This is the way engineering works. The alternative is called marketing.

I can't help it, I have to make one more comment. You said...

having pump curves from each manufacturer would make for an interesting academic exercise but I'm skeptical of the outcome since the curves are published by the manufacturer's with no oversight

This is like saying that Boeing doesn't need the pump curves for the hydraulic systems they design into their airplanes because the the vendors are going to lie. What nonsense. Its the reverse, you design a system and its pump to work together and pump curves are integral to getting that right. If you have x feet of head and need y gpm of flow you choose a pump that can supply that.

Either you don't get this, which astounds me as you hold yourself out as knowing something about the field, or you do but choose to bs people. Either way its shame.

I think if you review my posts on this (or any other forum) you will see I try to be polite and understanding but frankly you are just too much. Its assumed that we are trying to help each other here and so it just gets me to see you spouting such nonsense. If you don't know what you are talking about stay out of the conversation and if you do don't try to feed people a lot of disinformation.

So there you have it. I've called you out. Engineering is very dear to me and to see someone like you basically lying in order either make a point you can't otherwise substantiate or in order to cover up your own lack of understanding of how to design something really gets me. I've politely asked you to stop misleading people and you continue to lay on the bs.

No way to help people in my opinion.

sb...wow, we've really digressed, but I'll go down this rathole with you....first you discount the CEC data, now you're discounting and minimizing window efficiency publications and appliance efficiency publications.

How bold of you....these published metrics are industry accepted metrics based on tests and standards that are adopted by those industries. These standards and tests are developed by subject matter experts in the field of engineering for that industry. They meet regularly to review standards to make sure they are current and accurately represent the product being sold to consumers.

Appliance efficiency happens to be the business I've been in for 20 years and our appliances are systems made of components that all play a role in the overall system efficiency. We trust our suppliers when using their performance curves for our system simulations but we also verify their performance with actual test data in our system...being an engineer you've probably heard the phrase many times...trust but verify. No system manufacturer would knowingly release a product to their industry without verifying system performance with actual test data, not theoretical test data.

What the CEC has done is verified pump performance using a standard that was developed with input from pool industry professionals. Don't be naive and think this CEC test standard was developed in a vacuum and the results are misleading.

My guess is this body of work is just the starting point and will continue to bring the pool industry experts together to review these standards to make sure they are representing the purposed intent for the benefit of the consumer.

For now, the CEC data is the only source of information out there to my knowledge that provides comparative pump efficiency data using a standard. The results they publish represent actual pump performance in a system with different plumbing configurations representing typical setups in backyards. Are their assumptions perfect....probably not, but it's a great start and in my opinion the only true measure out there representing actual pump efficiency in a typical system.

You seem to be missing the fact that published curves are only good for academic comparisons and that actual test data from that pump in a system is the only true measure of actual pump performance...not curves published by the manufacturer.

The CEC data is actual data measured from pumps in a system and not academically derived from a curve. That's also why your examples of window efficiency and appliance efficiency are important measures that keep those industries working towards a common standard that will benefit the consumers...don't discount these standards and try to minimize them because they don't agree with your theoretical evaluations. If you want to continue to go back to individual pump curves for your comparison, remember those curves are just one component in the overall system efficiency equation and the results you derive are purely academic. It's real test data like that provided by the CEC that matters in the end.

mas985...Thanks for the feedback and running the numbers on NPV with 40 gpm for the Intelliflo vs 2 speed....Good stuff. I will certainly use your spreadsheet to help make a decision when it comes time to replace my 2 speed pumps....Hopefully, either the CEC or the pool industry continues to keep these published results up to date when that time comes.

Thanks!

trhought it is clear you know next to nothing about how these numbers are derived and what they are for.

Since you claim to be an expert, lets see what you know and what you don't, in particular, windows and pumps.

Windows. I'd ask that you describe exactly what the numbers one sees on a window mean? Are they a measure of the insulating value of the glass, the insulator between the panes, the frame or some combination of the three? Certainly if you are an expert you must know?

Also when you see a number on the window what exactly does that tell you about the performance of the window? Is the U value quoted the same you can expect for the window you actually buy or will it differ?

Finally will the number you see vary with the size or shape of the window or remain the same?

I'll bet dollars to doughnuts you haven't got a clue. You see a number on a window and think its everything there is to know about the performance and of course nothing could be further from the truth.

So its time to see what you know and what and what is bs. Tell us about windows. You can even use Google to get a quick education beforehand so you can get it right.

You so don't understand why these tests exist. They are to give a simple, but crude comparison between products so that consumers have something, however imperfect to go on. They are not a replacement for nor were they ever intended to replace real engineering data. You are so clueless about how systems are designed that you can't grasp this.

The test standard tests the pumps under a set of conditions and so only tells you about how the pump will perform under those conditions. It tells you nothing about how the pump will perform if the conditions are different. This is not a large leap of intellectual gymnastics to grasp this point. Its a crude, imperfect guide nothing more, same as the windows numbers you place so much faith in.

I'm flabbergasted you hold yourself out as an expect and can't grasp this. If you want to know how a pump (or a window) will really perform you can't rely on this information unless the pump is being used under that same conditions as the test setup. Is that so hard to understand?

So let's try this one more time. When an engineer designs a system and he is deciding, for example, what kind of pump to use he determines the operating parameter the pump need to fulfill (head and flow). He then specifies the appropriate pump using the manufacturers data (no they don't lie or at least they don't lie to other engineers). He would then compare various pumps by manufacturer and characteristics (cost, build quality, MTBF, efficiency etc) and choose a pump that fits the bill.

In comparing efficiency he would do that at the rated load (or loads). He isn't going to choose a pump based on its efficiency at a point where he isn't going to operate it. That isn't going to give him the correct answer.

The information you are so enamored with is useful at telling you performance only under certain conditions. Therefore it is useful under those conditions (I'm not going to start on how to interpolate between known curves).

It should be obvious that you need to know how much energy a pump will use for the load (head and flow) it will actually run at to know the energy it will use. Clearly you are finding this difficult so let me try one last time in the hope you will learn something from this exchange (or at least so that others will not be duped by your misinformation). If the sticker on a car tells you the car gets 30 mpg city does that mean you are going to get 30 mpg when you drive in the city regardless of whether you drive 20 mph or 50 mph? Regardless of how fast you start off the line, how hard you break, how much you spend sitting in traffic?

No the sticker tells you that the car was run through an industry standard running at certain speeds for certain times at a certain temperature etc the car got a certain mpg. Its a guide, a crude rough guide.

The pump test is much the same thing. It tells you how the pump will act under their test. Its not useless, but it can be wildly misleading or somewhat indicative of relative efficiency depending on a whole host of factors. This is why no one designing a pool should depend on them. They're a nice reality check but no replacement for a proper design. Particularly since it is so easy to do it properly.

CA came up with this so that consumers would see a good/better/best label and hopefully there would be a movement towards higher efficiency. That's it, nothing more. Just like a 55 mpg car is probably going to get better mileage than one marked 20 mpg its a broad brush measure.

But for heavens sake educate yourself before you start telling people a lot of stuff that isn't true. The idea of matching a single or double speed pump, properly sized to the plumbing is not a bad idea. But the only way one can tell how it stacks up is to have the real performance data for each pump and see how they compare. There is no other way and that you fail to understand this and yet continue maintain the contrary is not only wrong but a disservice to any who heed your advice.

But don't take my word for it. Call up an engineer or any engineering student and show him this thread. If you can find someone skilled in the art who says your going to get the right energy consumption by using numbers for one load when you are running at a different one, I'll eat my hat.

We all get it wrong once in a while, that is what makes us human. The test is how you react when you do. You're wrong on this one and its time you take the effort to figure that out.

You wrote...

You seem to be missing the fact that published curves are only good for academic comparisons and that actual test data from that pump in a system is the only true measure of actual pump performance...not curves published by the manufacturer

Are you insane? Do you even know what a pump curve is? The whole purpose of a pump curve is to tell you how a pump will perform ins a system. If that weren't true how would we build airplanes, front loads and whatever else uses pumps?

Pumps are characterized by putting them on a test bench and subjecting them to a certain resistance (head) and the flow and power consumption measured. This is actual data. How can you make such a statement?

I give up. For anyone else reading this since our poster clearly knows nothing about how the things he says he is an expert on works here is how it goes.

The pump is tested for performance. Actually many pumps are tested since there are manufacturing variations. The manufacturer guarantees the performance (there are a number of ways this can be stated but we won't go into that) so that bottom line you will get the flows you are promised and and the power consumption stated. I'm not going to get into an argument over the fringes of pumps that might not perform to spec. That isn't what we are talking about.

Engineers build and test pumps. Engineers specify them based on the manufacturer data, design them in and perform QC to confirm compliance. In a pool application you can skip the last step. Really.

I have no idea what this guy is talking about when he says pump curves are only for academic comparisons and frankly neither does he. The world of pumps would come to a screaming halt if buyers couldn't call suppliers and specify a pump based on the manufacturers curves with reasonable faith it will perform as represented.

Clearly this guy has never had the slightest experience with real systems. If he had then the first time someone asked him to go source a pump for a new project he'd be unable to proceed.

For those of you who do care about getting this right, its really quite simple. Just calculate your head loss (how much resistance in the system) and flow then look for a pump that will meets what you need.

So much talk, so much nonsense. How can you live with yourself? Do you just enjoy telling people stuff that is just plain wrong?

sb...most of what you said is so far off topic, I won't respond.

Regarding pump efficiency, if you read my other posts on this forum over the years, you will see that I did use pump curves from manufacturer's and had to make assumptions because most manufacturer's did not publish power vs. head so published pump amps was used instead to calculate power for the gpm vs head curves that are available. I knew this was not entirely accurate but was all that was available at the time. It was also then that I realized the Intelliflo (the only VS pump available at the time) could actually use more power at high speed than some of the 1 speed and 2 speeds for the same operating condition. Pentair later confirmed that in one of the posts. I can point you to any of these posts if needed.

In the absence of not having efficiency curves with power included, one has to make assumptions when calculating gpm/watt*hr efficiency and those assumptions can lead to incorrect decisions. That's why actual test data like that provided from the CEC is so valuable.

I've not been able to find pump efficiency curves for most pumps, you have not been able to find efficiency curves either, so one is relegated to making assumptions based on published data that is incomplete when noodling over theoretical efficiency calculations.

Why do you discount the CEC published data? Others on this forum and the TFP forum, are using this data to help make pump selection decisions and calculate NPV. Why are you opposed to doing this. If the answer is you want complete pump curves from the pump manufacturer's.....good luck on that one. In the absence of having complete pump curves from each manufacturer, the CEC data is the only reliable source of pump efficiency (gpm/watt*hr) to my knowledge.

Do you understand the CEC published data and realize the results are published in gpm/watt*hr units (true measured efficiency)....it is not some arbitrary grading system they came up with.

Hope this helps.

About 4 years ago, one of my clients installed an IntelliFlo VF on his pool in Sarasota, FL. He kept track of his electrical costs during the first year:

8/29/05 to 7/29/06 ------------- KWH = 24,583; total cost = $2,753.71

8/27/06 to 7/31/07 ------------- KWH = 17,334; total cost = $2,021.25

KWH savings = 7,249; cost savings = $732.46

This information is straight from his Flordia Power & Light monthly statements.

Make assumptions=you can get any answer you want.

Using CEC data for design rather than general guidance=bad design.

Lack of pump curves=lack of real answer. Yet you insist you know what the pump efficiency of these pumps are in real use.

I give up.

The rest of the post wasn't off topic. You just don't understand the topic and so fail to see how it relates. Simplified numbers developed to give a general indication of efficiency are inappropriate to use for whole system design. Its just as true for windows as pumps.

Run a pump at a different part of its curve from where you have efficiency data=different energy consumption. Assume the efficiency for where a different part of the curve=wrong answer.

No curves=no answer.

Done.

landa_mac, Great answer! I kept looking for tried and true response to this question. Thanks for sharing! :)

sbedelman,

I am really sorry you have chosen to dismiss this data so easily. The test methodology was developed with the help of the pool industry as well as the energy industry and uses sound engineering principles. So while you might not like it, the rest of the industry has adopted it. I would encourage you to take the time to understand how the measurements were done, what the results mean and how you can use them. But I think that you have missed the point of the data.

First, the data was not meant for designing a plumbing system, although there are ways to do that as well. It was developed so the consumer can compare the energy use of pumps. The CECs objective as part of Title20 is to reduce energy consumption so they wanted to give the consumer a tool that they can use to compare pumps. Before this data, there was nothing a consumer could use to compare pumps. This data can now give the consumer an "expectation" of energy use which is very pertinent to the theme of this thread.

I took the data one step further to allow the user to compare lifetime costs and savings of different pumps so they can make an informed decision as to which pump is more cost effective for their particular situation. The spreadsheet allows the user to customize the assumptions for their unique situation. But again, the intent is to allow the user to compare energy cost not different plumbing systems although to some extent, you can compare three (soon four) different classes of plumbing systems.

So anyone in the pool industry should take the time to learn the Title 20 requirements and the test methodologies used by the CEC because even if you are not in California, these regulations are likely to soon spread to other states. If you are in California, then it is extremely important that you understand the regulations.

mas985...Amen. We are seeing Title 20 influence on HVAC national standards also. California efficiency trends typically become adopted nationwide. I think this is because of the available power in California vs demand. Instead of building additional power plants to keep up with demand, the focus is more on reducing demand...especially during peak loads in the afternoon when it's hot outside and brown-out conditions start to occur. Other parts of the country are not faced with this problem so much, but going green is still the right thing to do and California is normally leading the way.

landa_mac....good information but this can be misleading because of all the other factors that affect annual power consumption. The way the data was presented makes it sound like all the power savings was due to simply changing to VS pump technology.

For this particular residence, it would be helpful to know some more about this residence before any power savings can be assigned to the VS pump. Information like original pump technology, gas heat or electric heat, size of A/C unit or units, efficiency rating of the A/C unit or units, Are the A/C units also HP units. What was the mean outdoor temperature each year for summer and for winter, mean indoor set temperature for summer and for winter. Does the pool have a heat pump, if so, what was the mean water setpoint for each year. Is this customer on a tiered power plan and if so did they try to minimize power usage during peak loads to get a better rate (it looks like the power company was charging different rates between the 2 years based on your data).

As you can see, there are many factors involved in answering the question the original poster asked. Claiming all annual power savings was due to the VS pump replacement is misleading.

It may sound like I'm being too analytical on this, but didn't want someone to read this and think they will also save $700 per year simply by changing to a more efficient pool pump.

Hahaha - this got totally out of control. The engineers and efficiency experts took this way out there. I guess I just accept that if someone reports they spent X during -2 year and Y during -1 year with no other comments, that all other factors are equal between the two years. But you do make a good point that some summers/winters are very different from the norm and could impact how many hours the AC or forced air unit was run.

Using Mark's spreadsheet, all the variable speed pumps are close in terms of cost of running them. I guess sbedelman wanted something that was totally customizable but for modeling cost of running a pump for X hours at Y rpm for the pool this was modeled after, it works great. The fact that he didn't bother to run the model was just closed minded on his part because the model backs up everything he says about efficiency of design being a big factor in savings (something I didn't believe until I ran the model).

As mas985 points out, there are 3 different curves. A is a decent design and similar to what I have. B is a old design using 1.5 inch pipe and some other factors like pipe length (which you can read about in his post/link) and C is more optimized than A so a "modern" design. The cost of running a pump for a month under the 3 scenarios turning over 24,000 gallons 1 time with 30% of runtime at high speed for vac and skimming and 70% runtime at slow speed filtering - oh, I am in CA so I used 27 cents/kwh so if you are only being charged 10 cents, your numbers will be very different:
Curve A= $49.54 with total runtime of 14.29 hours
Curve B= $71.33 running 24 hours
Curve C= $40.91 running 10.38 hours

For comparison, a 1.5 HP single speed pump using Curve A costs $101.60 for the month running 6.25 hours/day (so a projected savings of $51/month just by switching to a variable speed pump). What surprised me most was the difference in runtime between the different curves. Using the same pump, you run 13 hours less with a high efficiency design versus a poor design. The dollar impact of having a high efficiency design over the curve B design is as great as changing from a single speed to a variable speed pump.

BTW, under curve B, running 30% of the time at high speed cost $41.69 while low speed for 70% of the time cost $29.64.

Will this pan out in the real world with my specific pool? I don't know but I think it will be very close.

What's also useful about the model is if you have a variable speed pump versus a variable flow, it helps you model based on the rpm settings how long to run your pump to get X turnover.

I am still exploring which of the several variable speeds available to get. There seem to be pros and cons for all of them with the IntelliFlo and ePump having the highest efficiency but the Tristar energy solution being having the lowest cost.

Price the replacement motor the Hayward. Add in a service call. It is still and unsealed induction motor. It's still subject to many of the same failure conditions todays single/dual speed motors suffer.

The Pentair and Jandy are sealed, permanent magnet motors and significantly more reliable and better engineered. No dirt can get in. They run cooler too.

At this price point for a pump, parts aren't cheap. I want reliability. A few more dollars today to save myself from down time and expensive service costs 5 years from now is a wise investment, IMHO.

Scott

Don't forget that the replacement cost for the drive on the Intelliflo is nearly the cost of the entire pump and some have already failed after only a few years. Fact is that all of the varibles have a lot of expensive parts.

Also, from what I have heard, PM motors actually run hotter than induction motors since the rotor acts like a big heat sink and stores the heat but doesn't have as much surface area to radiate the heat. This is one of the reasons Hybrid pumps chose to go with the induction instead of the PM even though the efficiency may be less.

Good discussion guys....agree with everything poolguy, ttmatsu and mas985 said regarding pump efficiency, technologies and comparisons.

ttmatsu...you mentioned cost being an influencing factor in your decision. You may want to run some of the 2 speed offerings also for your comparison. I think you'll find the 2 speeds are also significantly more efficient than the 1 speeds and are not too far behind VS technologies. In addition to lower initial cost, the service costs of 2 speed pumps are significantly less than those of VS due to the reasons mas985 mentioned.

Hope this helps!

trhought - I agree with what you are saying. I recall talking to this elderly customer several years ago when he presented me with this data. I asked many of the questions you asked. His comment was that he had been paying roughly the same $2750 per year for his home's electricity for the last several years and was thrilled to see his bill drop to $2000. I know he has a propane tank in the yard. No heat pumps. The guy and his wife are in their 70's and there is not much variability in their electricity usage.

For what it's worth.

landa_mac....Thanks for the additional information. I think we're getting closer. At $.10-11/KWH, an expected $700 annual savings is high even if the original pump was a large HP 1 speed used in combination with average or sub-par plumbing.

If the original pump was a smaller HP 1 speed pump (.75 HP), a $700 savings is not right, even on sub-par plumbing. If the original pump was a 2 speed, $700 annual savings is not even close unless the 2 speed was ran at high speed most of the time and the lower HP option (.25 - .33 HP) was not used very much.

Also, outdoor temp has a large impact on annual power consumption...especially in warmer states such as Florida where almost every home has air to air HVAC systems. We track cooling degree days in HVAC closely and a swing as little as 2 degrees in the cooling season can affect power consumption 30% on an average home with same indoor temperature setpoint using an air to air system. Point being...HVAC equipment and outdoor/indoor temps have a significant impact on home power consumption...more so than any other system in a typical house.

One of the driving factors for me is that I don't have an automation system and I don't want one. Adding a controller to a 2 speed really brings it up into the range of a VF. A Hybrid pump requires a controller although 2 simple time clocks apparently can be used to switch between high and low speed. The advantage of the VF is that I don't need a controller - I can use the built-in timer to control when it is in each mode. Also, VF gives me a simpler way to play with the settings since I will always know the flow but Hybrid gives RPM like VS.

Scott, my pool guy is in agreement with you - stay away from the Hayward pump so it is down to the Hybrid and VF. Big company versus tiny company. Hybrid uses Invertek drive which is used in industry and a customized program is loaded by Hybrid. So the drive itself is available from other sources but the custom settings are only available from Hybrid. Pentair uses a custom made driver along with their custom code.

Pretty good doc by Pentair, almost zero doc available from Hybrid. Only about $150 difference between the 2. Without data, it's hard to make a decision in favor of Hybrid. It uses a conventional induction motor and what sets it apart is the Invertek driver and custom impeller. Heat is a known problem with low rpm use of induction motors according to invertek so Hybrid has a fan on the motor. Don't know if the claim about the IntelliFlo or PM motor having heat issues is true because Pentair claims the housing never gets hot to the touch and the fan is for the driver, not the motor.

I wonder if power surges or fluctuation is causing the driver in IntelliFlo to go bad. While it may not be bad enough to fry it, enough fluctuations can definitely shorten the life of electrical devices.

ttmatsu,

Have you talked with the guy at Hybrid? He seems to be fairly knowledgeable about the competition so you might get some insights into the Intelliflo that Pentair would never tell you.

In fact, I just finished talking to him. I mainly just asked him about the Hybrid pump with just a couple of questions about the VF versus X2.

John stated that there is no pump on the market that can move close to the same amount of water for the same energy consumed. For 2 inch pipe with a Sta-rite system3 DE filter, he estimates that at their default 1500 rpm filtering speed, the Hybrid pump would move 60 to 80 GPM using 1.8 amps. This equates to 230V X 1.8 amps = 414 watts. I searched TFP and found chemgeek listed a slew of speeds and wattage readings from his VF (60 GPM, 2710 rpm = 1305 watts). That's a little below what John estimated the VF would consume with my setup. If I drop the rpm to 1000 on the Hybrid, the amps would drop to 0.5 = 115 watts. Unfortunately, I forgot to ask him the GPM estimate. But it's obvious that he believes the hybrid to be the most efficient variable on the market.

Using the 1.8 amps for 1500 rpm moving 60 GPM (low end of his estimate for GPM), to turnover 32K gallons 1 time would consume 3.68kwh in 8.9 hours. According to your spreadsheet using Curve A, the VF at 1000 rpm would take 3.15 kwh running for 24.24 hours. Getting the VF to turnover in 8.98 hours requires 10.4kwh (using chem geek's numbers, it would be 11.6 kwh). Unfortunately, no CEC data to perform apples to apples comparison via the spreadsheet. But given that another X2 user on the forum reports using 2.2 amps using solar and running his waterfall, the efficiency could be close to what John states.

Replacement cost is another consideration I asked John about. Since the drive is the most expensive aspect of the VF with its custom application, the availability of an off the shelf driver for the Hybrid that they customize the programming on makes the cost much more reasonable - in the $300 range. The pump motor is custom made to their specs and they have not had a single failure in 3 years. John stated that the drive's job is to keep the motor safe so it won't allow it to run outside of pre-set parameters or it will shut it down.

I also found out that I won't need an automation system to run the X2. The drive has an internal timer which will allow me to run X time at vacuum speed and the rest at filter speed. My intermatic clock would control on/off like it currently does for the single speed.

Hybrid also has a 2 year warranty on everything. The only question left is longevity of the company itself. Can they sell enough and get PBs to start using their product to stay in business?

I'm really impressed after running the numbers.

ttmatsu, I have been following this forum with much interest as I am considering changing my pump to VF or 2 speed. Can you PM me at vat-19@juno.com? I would like to hear more thoughts on the Hybird X-2
Thanks in advance

ttmatsu,

I think some of your concerns are warranted. They are a new company and have yet to fully prove the reliability of their pump.

Also, I would look at the performance somewhat suspiciously. A pump cannot be 100% or more efficient. Pentair claims that the Intelliflo motor is 92% efficient but the total pump efficiency (WHP/EHP) at best is only about 50%. The Hybrid might be able to improve on that with a high specific speed impeller but I doubt that could be better than about 25% and most likely less.

For a fair comparison, the complete operating point of the Hybrid must be known. So if you can ask them what the head loss is at 60 GPM, then you can have a better comparison. Also, for every pump on the market, the energy consumption is dependent upon flow rate so the pump should have higher amps or watts for 80 gpm vs. 60 gpm.

Hi All,

I would appreciate if some one help explain whats going on with my Intelliflo VF pump.

I have a VF that was running for about 22 Hrs turning a 20K pool once a day. It was running at around 16 GPM and it ran fine for over a month. 16GPM x 22hrs ~ 20K gallons.. Perfect.

Then I introduced solar heating and programmed feature 3 on the pump to 30 GPM for 5 Hrs a day. The rest of the time the pump is scheduled to run at 16 GPM.

It starts at 6.00 AM and runs at 16 GPM till feature 3 kicks on at 11.00 AM. So thats 5 Hrs which equals 16x60x5 = 4800 gallons

From 11.00 am to 4.00 pm feature 3 runs at 30 GPM. So thats 30x60x5 = 9000 gallons.

At the end of feature 3 total gallons filtered = 4800 + 9000 = 13800

The pump then goes into power save/sleep mode which it is supposed to do when it thinks its finished the cycle sooner than necessary. But there is still about 6200 gallons to filter which means the pump should have ramped down to 16 GPM and run for at least 6 hrs.

Am I calculating something wrong ? Can some one explain to me whats going on ?

Pentair's "So called" Technical support had no clue and they rudely hung up the phone saying that no one can say what the computer calculates. This is exactly what they said. Pentair has the worst technical support team ever.

Please help..

Please start a new thread.
Yes, it's weird. Something isn't right. We'll help you find it.

Scott

Being a new user I apologize for posting in the wrong thread. I have started a new thread "Intelliflo VF incorrectly calculating timing and GPM. Please Help"

Would appreciate some help.

thanks