Open loop pump short cycling

Discussion in 'Open Loop' started by LT1Pat, Dec 25, 2010.

  1. LT1Pat

    LT1Pat New Member

    I have two geothermal setups and here are the facts I'd like to keep in mind with with the question I am about to ask:

    -One 4.5 ton (6.75 gpm on stage 2)
    -One 2.25 ton (3.375 gpm)
    -Pump feeds house as well
    -73' deep well
    -26' of drop pipe (so pump might sit 40' deep?)
    -pump is a 10sq05-160 (10gpm)
    -pressure switch is 40/60
    -pump appears to more than 10gpm (14+ verified by flow gauge)
    -I am happy with the pumps ability to keep up with house+open loops

    My pump is being short cycled with the addition of the second unit and instead of buying pressure tanks I was considering possibly switching to a SQE pump and controller. The pump runs a long time when the systems are running but once it reaches the shut off point it will turn back on shortly once the bladder tank draws down. At the current rates I don't think my pump will last long but that's why I am trying to find a solution.

    I'm having a hard time researching if a CSV is a real solution since "Valveman" ends up overpowering every thread with biased information no matter what site is posted on making google searches about his product frustrating. I am legitimately interested in using one of these valves with the knowledge that a lot of his math appears to be flawed. The question I have is if my pump is already sized to almost the maximum of its ability of a CSV is a good solution or not.

    Given the following information which would likely be the best solution giving a good balance between longevity, monthly bills, and initial install price.

    1.) Adding pressure tanks to extend the time between the pump shutting off and starting back up

    2.) Adding a SQE pump/controller to reduce cycling and increase longevity

    3.) Adding CSV

    4.) Any combination of the above 3 and dropping the pressure down to 20psi or so with a pressure booster to supply the rest of the house
  2. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Hi and welcome,

    There is a opus on this forum that I will call "ode to the csv". It was closed and locked by the administrator. When valveman called my office and talked with me personaly, I decided to decline his offer of a free unit, but did go back and edit all posts in that thread that filled with emotion and not data, everyone deserves to make a living.

    Your problem is the age old question "how to solve the riddle, robbing peter to pay paul".

    1. Adding tanks will extend the run time but is costly in material costs, consumes space, and water will warm to ambient temps when times of low usage occur, stale tasteing.

    2. Adding variable speed equiptment is costly, minimum of 1k to get in the game. It is the only way to truly address your issue from a standpoint of engineering up front for a given condition. It is not a fix or work around.

    3. A csv is a work around for bad upfront engineering. It is a fix to a problem, not a solution. I do not sell or install any type of csv, period.

    4. This is the worst choice as it will not address pump capacity at all. The lower the pressure the higher the flow from a given pump. It will consume space for the storage vessel and get overly complicated while not really addressing the problem.

    The real problem is needing a variable flow rate from a given pump. A pump that is designed for variable operation is the logical choice. Grundfos is my least favorite of available products.

    Geothermal systems do not require high pressures to operate. We install variable speed pumping equipment when doing installs and do not bother with pressure reduction unless water noise becomes and issue in the units.

    I want my cookie now for not saying "Ahhh the magic beans".

  3. LT1Pat

    LT1Pat New Member

    Thank you very much! My well guy said I needed a 3" pump but my steel casing looks at least 4". He also said a csv was way better than a vfd drive so now I don't know if he knows what he's talking about. Are there any other pumps that wouldn't require me to add underground wiring that doesn't already exist for my 230v grundfos pump? Is the sqe marginally worse or A complete failure of a design? I ask because I can get the whole system fairly cheap.

  4. Bergy

    Bergy Member Industry Professional Forum Leader


    Eric being calm about a CSV...One of the seven signs maybe?:D:D

  5. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    Do you guys throttle the outlets from the HPs? At house pressures way way more than 1.5 GPM per ton will flow through a geo heat exchanger.
  6. LT1Pat

    LT1Pat New Member

    I use a blue white flow meters and ball valves to regulate the water flow. When the pressure increases it's also a bit frustrating because the flow rate varies with the pressure. I set it so that at a minimum it always get 1.5gpm/ton but when the pressure shuts off at 60psi it's flowing closer to 2gpm/ton.

    I think a variable speed pump is what's right for me.

  7. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    Don't sweat the 1.5-2.0 GPM issue - the extra 1/2 GPM matters little.
  8. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Franklin electric makes a 2 wire vfd controller for retro-fitting existing equipment to vfd, but it is 1k retail. My opinions about the grundfos unit is two fold.
    1. the units have 2 electronics packages. one in the pump and one in the box. the most frequent fault we saw was no communication between the two. way to complicated for a water pump.
    2. horrendous dealer tech support from corporate. we thought that having got behind their product early and having allready purchased 100+ sque packages from them that we could get some support. they did not care, they left us hanging and swinging in the wind. They went so far as to tell a commercial client of ours that we did not know how to install their product.
    That prompted a "haitian divorce".

    As far as the csv and your pump guy is concerned, many people believe what they are told. Ask him how long he will warrant your pumping equipment after the csv is installed. If he will give you a 5 year parts and warranty on the csv and your pump, I would sign up in a minute. If he will not warranty that pump for 5 years post csv than that would tell me alot.

    A work around that will save your current pump set up would be to wire your solenoids to all come on if the small unit calls for water. This will get the pump up and running non-stop to extend pump life, but be extremely wastefull in regard to the water and the electric consumption, there is no easy solution.

    Are you comfortable changing your own pumping equipment? That 10gpm 1/2 hp pump is the 1/2 ton pick up of water pumps. If you get away from grundfos and buy another brand to keep on hand the investment will be around 300.00 wholesale and about 30 minutes of your time.

    Hope any of this helps?
  9. LT1Pat

    LT1Pat New Member

    Very helpful! I think since my pumping needs are already so close to the max that a VFD would be best. The first stage of my geothermal for the main house runs non-stop in the winter months so with a VFD I doubt that the pump would shut off once from November-February so cycling would be non existent. It would also be very nice to have constant pressure for showers.

    I'll probably install the VFD system and then keep the grundfos around as a spare. It was originally installed in 2002 so at this point I would consider it a great pump.

  10. Valveman

    Valveman Guest

    It would tell me a lot, if a pump man doesn’t already know that a VFD decreases, and a CSV increases the life of pumps and motors. The CSV is the “solution” to your problem. And people who admit to having NO experience with them should refrain from making false statements.

    Since the CSV has proven to increase the life of thousands of pump systems, any pump man with experience with CSV’s will have no problem warranting everything for 5 years. I have always stood behind CSV installers by personally offering to warranty any pump or motor that was damaged in anyway by the proper use of a CSV. However, in 18 years and hundreds of thousands of installations, there has yet to be a single pump/motor damaged by a properly installed CSV.

    I know why some installers and all manufacturers do not like CSV’s. CSV’s make pumps last longer, use smaller pressure tanks, and replaces VFD’s, which dramatically cuts into their repeat business. And if my math were “flawed” one or more of these manufacturers would have sued me by now. I am continually astonished by end users who discover the CSV can solve their problems, are offered a money back guarantee on the CSV, and a personal warranty from CSV on their pump and motor, and still have reservations. I guess it proves the old saying that “you can lead a horse to water, but you can’t make him drink”.

    Anyway, if the fine folks on this forum will allow it, following are several quotes from people who have experience with CSV’s. #1 is from an engineer. #3 is from a well-respected driller and installer. #4 is from a NASA engineer. I am not posting full names, phone numbers, email addresses, or pictures, but they are available if anyone wants to contact them directly.

    Thanks for the compliments and especially your helpful advice to "fine tune" my system. Please feel free to use any info that I have sent you as I would want others not to suffer the costs & hassles of the VFD experience. The Grundfos VFD does look impressive initially, and it might have worked better with a separate signal wire from CU301 to pump. The voltage variations kept disrupting the frequency info it was trying to send to the pump receiver. But, it would still cost more than the CSV solution!!

    I must say that I have been a fan of Gould and Grundfos pumps for over 30 years, but I am really disappointed with the VFD design as they have implemented it. Older pumps lasted for decades! I hope to get a few years out of my SQ(E) pump. I will contact you when it goes for a private suggestion for a replacement.

    As an old engineer type, I really enjoyed and appreciated all the info on your site. Now that I have the CSV installed, it really is nice not having to check the VFD LED lights for proper system function every day!

    After reviewing your site's info, it was easy to do the numbers to kill the VFD. Your CSVZ1 plus a pressure switch ran > $200. To diagnose and change operating parameters to the VFD, I would need to buy the Grunfos R100 at $200+. Then if that did not work, I would have to replace the CU301 (~$400) and then possibly the pump (~$800) plus labor!! Way too much money!!

    I will keep you updated with my progress after implementing your suggestions. I will include any new pix as warranted.

    As a note, almost 2 years ago I picked up the "discussion" on VFD versus CSV on Terry Love's forum. That was a quite an extended and "lively" debate with a number of experienced and seemingly knowledgeable folks in the field. Everyone was sighting facts,
    figures and experiences to support their individual camp. I had originally gone to that forum to research Standing Column Wells. Lots of arguments and opinions on that and GWHP systems as well!!

    As you can see, I sided, at my expense, with the VFD argument. Experience is a great teacher!

    So far, I am delighted with this CSV solution! Your communication and interest in solutions for folks such as I is exemplary!

    I have attached an updated diagram of my system with the yard hydrant erased, so as not to confuse anyone. I will take your suggestion to tap it off and I will move it to another location after the CSV.

    Also, for your interest, I have attached another diagram that I drew of my GWHP Standing Column Well system. I used these diagrams to explain my system to my local county building departments.

    Thanks again for the CSV solution and your tips to fine-tune my system!


    “Hi Cary.
    Well, the CU301 was running well when you and I last talked, but last week and again this morning the water pressure felt low to me. This morning I ran downstairs and sure enough, just under 40 psi with just one shower running. Same symptoms as before the CU301 was replaced for the 4th time. Not looking forward to going for #5.

    I have to think that I’m not the only one having this problem.

    Richfield, WI”

    We are faced with a huge vfd push here in our area unfortunately we have been caught up in it as well and now we are realizing that it is just not a good product as far as life of the components are concerned or energy wise. We have used your products in the past and now realize how much of a mistake the vfd can be for repeat business. We would like to help promote your product as well as installing them for our customers.

    Jeff Coppo
    Contoocook Artesian Well Co. Inc.
    Since 1936 - N.H. License #1”

    Thanks much for all your support. Your product is performing great. Attached are pictures of the installed unit and pics of the Ares test rocket that's parked right outside the building where the pump is located. You can also see in the background one of the retrieval ships that tows the spent rocket boosters back to this facility. Thanks again for all your help in making this a successful project.

    Randal B. Mick
    USA SRB Facilities Systems Engineer
  11. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    So will the pump man offer 5 years warranty parts and labor post csv??? That is the only question. I ask the same question of anyone selling me anything. No matter how passionate the pitch, the truth lies in the gaurantee if the money comes out of the sellers pocket not the consumers.

    It is a quantum assumption you make about my skill set and knowledge via the internet. Now I will cease to speak so Phil does not ask me into the principles office again.
  12. Valveman

    Valveman Guest

    Me too! Sorry! The money does come out of the sellers pocket! I hear from sellers everyday, that they should have tested things more carefully before they went the other way.:)
  13. LT1Pat

    LT1Pat New Member

    This horse isn't drinking the water. As a mechanical engineer who has taken fluidynamics I saw your math in another thread (on this forum) and it was very flawed or you only show the math that think benefits your argument. As a geothermal forum we are all concerned with energy usage and there is no denying that building pressure consumes energy and that's all you valve does. It converts the flow of water to artificial head slowing the pump down while building a ton of pressure before the valve. It's possible that the amps decrease but that doesn't also mean that there is a lot of energy being wasted. Your valve is very simple and just like you always say about VFDs "The technology has been around for decades!" which applies to your valve as well.

    Numerous third party tests have been done on your valve and they show dramatic increases in electrical usage and on a geothermal forum that would be bad news. It also seems like you have that terrylove forum strictly moderated to only benefit your product. It also seems like you tell people to ditch their VFD systems for a CSV system disguised as an average user which bugs me because they don't realize you plan to benefit financially from your own advise posted on a public forum.

    Don't you find it ironic that almost all the negative posts towards VFD's and just about every forum originate from your usernames? The fact is that building back pressure consumes energy. This isn't even taking into account the issues that can results from excessive back pressure before the valve on the piping and pump, lack of cooling across the pump, pressure put on the bearings (which may or may not be an issue). I have a feeling that installers of your valve don't understand the amount of pressure being built before the CSV.

    The fact is that you would be a great lawyer. You seem to be able to skew any conversation and take no for an answer even though you have tons of facts opposing what you say. You are a great salesman but it bugs me when you conceal facts, trash the competitors, trash VFD technology and litter public forums with biased information.
    Last edited: Dec 28, 2010
  14. Valveman

    Valveman Guest

    Thanks! But I can’t take the credit. My “math and cleverly worded responses” come from information right off a pump curve. And my “biased reviews” are direct quotes from pump installers and engineers who have actual experience on this subject.

    I would have said, “enlighten” the uneducated, and engineers who know all about (and I think it is spelled) “fluid dynamics”. Since you know more than the NASA engineer or the NH Driller with license #1 that I quoted, I will acquiesce. I wish you all the luck with the VFD.
  15. Valveman

    Valveman Guest

    A lot was added while my last post was being “moderated”. Please let me address these other points.

    I don’t find it ironic that I am the most vocal in my negative attitude towards VFD’s. Nobody else wants to be subjected to the vile and venom such as this from people who don’t want to hear the truth. I always feel like I am one of the few willing to stand up and say, “The Emperor is not wearing any cloths”. But you know what, the Emperor is really not wearing any cloths.

    I spend time explaining the problems with VFD’s because I believe it is the right thing to do. Believe me, a few small inexpensive valves on Geo systems do not pay for the time I spend explaining things like this. Somebody has to stand up for the general public, because they are not educated enough on this subject to argue the points.

    Manufacturers, suppliers, installers are raking in the dollars on the false pretense that VFD’s save energy. Engineers want the VFD to be the panacea that solves ALL their control problems, and keeps them from having to actually know how to size a pump to the exact requirements. Even government agencies give rebates and tax incentives for installing VFD’s, as they want to show people they are trying to help reduce energy consumption and keep the planet green to justify their jobs.

    A VFD is a Harmonic Generating Energy Hog. But you won’t hear anyone in the VFD industry admit that. Enthusiast will also tell you that a VFD saves energy by the cube of the speed, but they always fail to mention (or don’t know) that a VFD also causes a lose in head by the square of the speed, which greatly limits any possible reduction in RPM. Any line or load filters added to reduce troublesome harmonics and voltage spikes from VFD’s waste even more energy. The square wave generated by the VFD also decreases motor efficiency by several percent. The VFD controller also uses power (parasitic losses) in addition to what the motor needs, and it continues to use power even when the pump is turned off. The Affinity Law only applies when two points on the curve have the same efficiency, and very few people know what that really means. The room where the VFD is installed is usually air conditioned, which uses even more energy. Plus harmonics generated by VFD’s dirty up the power supply and make everything in the entire electrical grid less efficient.

    Then there are the destructive problems caused by VFD’s. Harmonics and voltage spikes add heat and stress to the motor, shortening its useful life. Bearing currents destroy ball bearings. Resonance Frequency Vibration is always a problem when the RPM varies. And this is just the short list.

    I am not the one concealing facts. I was building and installing VFD’s myself until 1993, when I realized most jobs could be better accomplished using a simple valve. I should also say that I am a big fan of electronic technology. I built a computer from scratch in 1977 and am still a gadget nut. I think VFD’s are marvelous machines when used in proper applications for things like treadmills. However, I know for a fact that VFD’s waste energy when used with systems designed to produce constant head. Many people promote VFD’s for that use just because the market is so large, and right or wrong they want a piece of it.

    Yes increasing pressure on the pump does use more energy per gallon the same as slowing a pump/motor with VFD causes it to use more energy per gallon. Many of those in the VFD camp will say, “reduce the RPM of the motor, the amps decrease, so you are saving energy”. They won’t tell you that even though it is reducing the energy needed to spin the pump/motor, the VFD system is using 4 to 5 times as much in energy per gallon produced.

    The issue of backpressure was addressed almost 20 years ago, and never held water. Backpressure does not overload bearings, and actually causes a submersible motor to require less cooling flow. Many savvy installers and engineers understand that extra backpressure is not harmful and just makes the pump think it is in a deeper well. They also know how to specify pipe and fittings accordingly.

    I am not disguising or hiding anything. My screen name is well known as well as my real name, address, and phone number, unlike (others). It would be very easy to find me and sue me if you can prove anything I have said is false. Get in line though, because there are lots of big manufacturers who would love to shut me up. Proving I said something wrong is the problem, because my statements are accurate. And VFD manufacturers do not want to go down the road of which one of us is not telling the truth. Most of the angry I see is from those who just found out they do not understand everything there is to know about “fluid dynamics”.

    Thanks for the compliment, but I would not make a good lawyer. I am rarely able and never willing to skew a conversation unless the facts are on my side. Over the years I have given many classes on this subject. In auditoriums with a couple hundred engineers, pump installers, and manufacturers, I have said these same things. Most don’t like what I say, but they have never been able to prove me wrong. They refuse to give a class at the same event, or go up against me at a round table discussion, as it makes them look foolish. I will be giving another class at the Texas Ground Water Association meeting on January the 26th. I would love for you to come heckle, as I would appreciate the opportunity to argue these points face to face.

    There is no more efficient means of moving water than properly sizing a pump to run at BEP, controlled by an Across The Line starter, with a little power factor correction. Then if flow needs to vary while the head remains constant, a valve can be just as efficient as a VFD. As a geothermal forum we are all concerned with energy usage, so we should get the facts straight and not be led by emotion or myth.

    I will attach a few links to articles that were written by others, so you can see I am not the only one brave enough to tell the truth about VFD’s.
  16. Looby

    Looby Member Forum Leader

    Anecdotal evidence ...ain't.

  17. Forum Admin

    Forum Admin Administrator Staff Member Forum Leader


    Your posts have been moderated since your inflammatory post a few months ago to prevent your posting of more inflammatory comments. You have been absent from the forum until recently but your new posts indicate you are still committed to putting forth the same old info using a style that is more argumentative and narcissistic than it is contributory and useful.

    A few observations:

    Your participation on this forum is first and foremost to promote a technology that when deployed benefits your company directly but may or may not benefit consumers which happen to be the primary audience of the forum.

    You have stated your position countless times and posted numerous links to support your beliefs and opinions. Said posts and links are available to the forum readers by searching "cycle stop valves"should they have an interest in CSVs.

    You repeat the same old theme over and over without offering new info or displaying an interest in technically substantive discussions.

    My conclusion:
    New threads on the CSV topic will not be approved unless they are in the Industry Professionals Forum
    Existing CSV threads will remain open for members to resurrect if they feel the need.
    Your user account will be set to "Banned".

    I don't like taking such strong actions but the interests and needs of "Forum Community" trump yours.
    Last edited: Dec 29, 2010
  18. LT1Pat

    LT1Pat New Member

    I just wanted to summarize a CSV for the people who are looking for a straight to the point answer when they search this topic in the future.

    - CSV will dramatically increase your electrical usage in almost all applications. Valveman tries to cover this up trying to say it's negligible or it's not typical.

    - Piping before the CSV needs to withstand much more pressure than originally due to the way the CSV works. It is nothing more than a pressure reducing valve with a relief allowing water to bypass when it is closed.

    - Even though amps decrease due to less work being done, it is not proportional with the amount of water pumped. The amps might decrease 20% but the amount of water being pumped will decrease 80+% (efficiency goes out the window).

    - Almost all negative VFD posts on different forums can be traced back to people involved with this company or people who falsely believe information posted by his company.

    Valveman most likely uses search engine "key word finders" to search the internet every day to find new posts relating to his product. When he finds the posts he will bash any other products that may interfere with the sales of his CSV.
  19. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Valveman most likely uses search engine "key word finders" to search the internet every day to find new posts relating to his product. When he finds the posts he will bash any other products that may interfere with the sales of his CSV.[/QUOTE]

    This would be evidanced by his lack of involvement here, except when someone uses the three magic letters VFD.:D
  20. LT1Pat

    LT1Pat New Member

    I think you meant CSV :)

    He loves it when people bash VFD's but unfortunately he seems to be the only one doing it. I have been using VFD's for many years to run equipment and they are a great invention. I've dropped them, got them wet, machine dust has got in them, power outages and surges, metal shavings and coolant splattered over them, had them running 24/7 and they still run strong.

    This would be evidanced by his lack of involvement here, except when someone uses the three magic letters VFD.:D

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