Check valve between pump and tank

Discussion in 'Pumps and Tanks Well Forum & Blog' started by Dave Meers, Sep 9, 2007.

  1. Dave Meers

    Dave Meers New Member

    Messages:
    12
    I'm sure this topic has been covered before but I did't find the thread when searching.

    Should a check valve be installed between the submersible well pump and the pressure (bladder) tank? I know that all (oe most) submersible pumps have built in check valves but there seems to be some conflicting information as to whether a second check valve helps or could cause problems.

    So what do the Pros on this site think? Thanks!
    Last edited: Sep 9, 2007
  2. patrick88

    patrick88 Plumber

    Messages:
    836
    Location:
    Webster Ma.
    i have always installed a valve before the well-troll tank. I have always done it and everybody i have asked says you need it.
  3. Rancher

    Rancher Guest

    You don't need a second check valve and it can cause problems.

    Rancher
  4. patrick88

    patrick88 Plumber

    Messages:
    836
    Location:
    Webster Ma.
    this is the Tech file as a pdf for the only brand i install and would use in my own house never had any problems with them. The info you are looking for is on page 43 of this pdf>>http://www.goulds.com/pdf/TTECHWP.pdf <<

    it is very clear and even has a drawing.

    hope it helps
  5. I always install a check valve on the suction side of a shallow well pump to hold prime, but I've never seen one between a pump and pressure tank. Don't know why you'd need one on a deep well. Just MHO.
    Mike
  6. abikerboy

    abikerboy DIY Senior Member

    Messages:
    202
    Location:
    VA
    I learned this from both helping out a friend, and from a personal experience as well. First of all, around here they will fail inspection of any check valves that are outside of the well casing. Even with a jet, you have a foot valve, and they wont allow a check valve outside of the well except with a non bladder type tank. My personal experience, submersible pump, with burried tank plus check valve at the tank tee....got a lot of mud in my water in spurts. Tank had failed and was leaking, PLUS a clamp had rusted away in the poly pipe between the well and tank. The leaking tank would make a pocket of water around it in the ground, and when the pump stopped, the drop pipe in the well would drain, creating a vaccuum on the joint beside the tank in the pipe with the rusted clamp, and it would draw the dirty water back into the pipe, and down the well. What I have always been told was that the check valve would cause water hammer, and that if a drop pipe should start to fail, you'd never know it with an external check until your pump dropped off and fell down your well...BUT...the inspector here said that the mud and contamination that I had at my faucets from the failed tank and line was the one single reason that they will fail any check valves outside of the well casing unless you have a galvanized tank and snifter type set up! The old style tanks rely on the line draining, and that spurt of air to refresh the air charge on the tank. Ive read some pump manuals that say to install a check every so many hundred feet in the drop pipe of a sub pump, but with helping out a buddy and learning a lot from this pro, he always relies on the check in the submersible pump alone, and Ive seen many pumps set at 1000+ feet, and have helped him pull many set at that depth with no checks anywhere other that on or in the pump.
    Last edited: Sep 10, 2007
  7. speedbump

    speedbump Previous member

    Messages:
    4,540
    Location:
    Riverview, Fl.
    abikerboy is absolutely correct on all points.

    Go Figure: The moron Plumbing inspector who is in charge of the Well Drillers (this week, they keep putting us under different organizations, last time it was the Building Dept) took it upon himself to make it mandatory to install a Union and Check Valve at the well head of every new installed well. This is the County, not the State. I tried to explain exactly what abikerboy stated in his quote, but it went right over this idiots head. So how safe do you feel about your well inspections in Hillsborough County now???

    bob...
  8. Dave Meers

    Dave Meers New Member

    Messages:
    12
    Layman's Summary

    Thanks for the input. It sounds like there is less than total agreement on installing a second check valve before the pressure tank. The pump manufactures seem to require it while a few of the Pros think that it will cover up a problem with a defective check valve at the pump and possibly cause a pressure spike each time the pump turns on. The pressure spike could cause the pump to separate from the down pipe resulting in a major problem with removing the pump.

    Have I missed anything with this brief layman's summary? I certainly appreciate the feedback. The only part I'm still not clear on is why do the manufacture's think it protect the pump and will void your warranty if one is not installed.
  9. speedbump

    speedbump Previous member

    Messages:
    4,540
    Location:
    Riverview, Fl.
    I have never heard of any Manufacturer requiring another valve to maintain warranty. If so, they wouldn't put one on the pump.

    When you get a hole in your droppipe or in the horizontal line to the home without the above ground check valve, your pump will cycle occasionally to keep the tank pressured up and to alert you of a problem. The pipes will always be under pressure, so water can only leave the pipe. With the above ground valve, the pressure pushes water out of the pipe, then when the pump turns off, the valve up top contains the pressure in the tank and the hole in the pipe is now under vacuum pulling that water and whatever else into the system. Yuck!
  10. Dave Meers

    Dave Meers New Member

    Messages:
    12
    Apparently, Goulds requires additional check valves every 200 feet above the pump per the technical data publication that Patrick provided a link to - so you could end up with more than two valves with a deep well. It also says that water hammer is caused by the water column reversing directions when the pump shuts down, developing a large amount of pressure downwards on the down pipe. They do refer to Flomatic valves as a type of check valve designed to control these high pressures. Is a Flomatic valve really different than a typical check valve? Just trying to understand the logic behind using or not using these valves.........Thanks again for all of the input.
  11. speedbump

    speedbump Previous member

    Messages:
    4,540
    Location:
    Riverview, Fl.
    You can put ten check valves in the droppipe if you want. You won't have any less water hammer than you do with one valve, the one on/in the pump. If you add a valve at 200 feet above the pump and the one in the pump goes bad, you will then have water hammer each time the pump restarts. You can listen to Goulds Engineering Dept, or you can listen to around a half dozen experienced pump people here tell you different.

    bob...
  12. valveman

    valveman Moderator Staff Member

    Messages:
    4,549
    Location:
    Lubbock, Texas
    I concur with Speedbump. To many cooks spoil the meal. To many check valves spoil the system. Most information published by pump and motor manufacturers was written many decades ago, when extra check valves were needed to help air charge the old style galv pressure tanks. The people who wrote this stuff are long since retired and gone. The new engineers for the pump companies are usually fresh out of college and have absolutely no experience with pump systems. They only know what is in the old tech manuals and have no idea why certain things work or don't work. Also, it may seem unbelievable but, most pump companies are not forthcoming with the best info on how to install a pump system or how to make pumps last longer. They will usually give you the info that will at least make your pump system last through the warranty period. Other than that, they like to sell pumps so, they don't tell you everything. Experienced pump installers know more about how to set up a pump system than the manufacturers. Pump installers are also not encumbered with the restraints of trying to promote "planned obsolescence" as engineers for pump companies are. Knowing how to install a pump system correctly, can double or triple the life of a pump that was designed and manufactured to last an average of only 7 years.
  13. Wet_Boots

    Wet_Boots Sprinkler Guy

    Messages:
    798
    Location:
    Metro NYC
    Do note that the check valve advice from Goulds is being applied to a wide range of pipe sizes, with 10 and 12 inch check valves being mentioned. There would have to be a point in larger systems where you'd want to subdivide the mass of water in the drop pipe. With poly drop pipes of 250 psi ratings available, I'd wonder how much protection your generic home well-water system would need.
  14. valveman

    valveman Moderator Staff Member

    Messages:
    4,549
    Location:
    Lubbock, Texas
    At the bottom of a well, the pressure on a check valve with 12" pipe is the same as the with 1" pipe. Actually, the larger the pipe and check valve, the worse the symptoms are from multiple check valves. The water hammer that is caused by multiple check valves can knock a thrust bearing out of a motor and many other problems. Multiple check valves may sound like a good idea but, in real life they can cause lots of problems.
  15. Dave Meers

    Dave Meers New Member

    Messages:
    12
    Thanks for all of the input from the Pros on this forum and to Terry for making this site available. It sounds like one check valve is all that's needed.
  16. Raucina

    Raucina Previous member

    Messages:
    515
    Goulds wants to sell pumps and our moderator-censor wants to sell his valves. Basically we are screwed by slanted info.

    So we got a half dozen unknown internet pump people up against Goulds engineering department [20 - 50 -80- gentleman?] But our moderator says they must be liars trying to put out information designed to break their own pumps.

    Sad place this is.

    If we really had some pro's here they would discuss velocity flow, design of the check valve and speed of closing.
  17. abikerboy

    abikerboy DIY Senior Member

    Messages:
    202
    Location:
    VA
    I will state upfront that I am not a pro. Just an average joe working with a buddy who has been in the business since the 1060's, trying to earn a few extra bucks doing his "gopher" work. I know the problems I had with my own well caused by an "illegally" installed check valve outside of the well case. Dont know whether to say "install a valve every 200 feet" or not...just know that here they will fail you if you have one OUTSIDE of the well case! Helped my buddy pull a flint and walling pump, set at 375 feet, and original from the 1970's...only check was one on the pump, BUT a snifter at the pitless and a check at the tank was removed in 1977 when the steel tank was replace with a wellxtrol bladder tank in 1977...still the same wellxtroll tank in there too! That well has served two full houses all of these years. Also getting ready to help another friend pull a pumps...served two houses and a mobile home, was installed in 1979 and is original. Only check is on the pump, 420 foot deep, and tests confirmed that the check is in the well. Ive learned that what the guys who have been in the trade for 20-30 years know is much more valuable than what some corporate guru earning 150k a year will ever be. Take the simple automobile for example...buy a car in the mountains of colorado, drive it to the beach and spent a summer. Owners manual says that any tampering with the fuel maps (mixture) voids the warranty and is illegal, but your new car that got 30 mpg in colorado will get about 20 at sea level, and that engine will die an early death from fuel washdown of the cylinders without some "tweaking", warranty approved or not! My point is that some things are learned from experience, not from a manual...if it were as simple as a manual, hell, any of us could be pump men, or doctors, or lawyers, etc! Most goulds manuals (ask any goulds rep) were written in the very beginning, and have been requoted over the years. After months of drinking mud, no checks above ground for me. I will agree with the county inspector on that detail from now on...not with goulds. Oh...velocity...one goulds manual says not to exceed 6 fps...another says up to 13 fps is safe...both printed by goulds. Which one is correct?
  18. Wet_Boots

    Wet_Boots Sprinkler Guy

    Messages:
    798
    Location:
    Metro NYC
    So there is no limit to the depth and size of drop pipe you are comfortable in having in a well in your care? The mass of water must have some place in Goulds' calculations.

    Goulds doesn't even sell the Flomatic check valves mentioned in their manual, so I don't think that greed enters into it.

    It would be illuminating to read more discussion over why the information about check valves is in their manual in the first place.
  19. valveman

    valveman Moderator Staff Member

    Messages:
    4,549
    Location:
    Lubbock, Texas
    Raucina, I never said anything about a Cycle Stop Valve in this thread. However, now that you mentioned it, I will say that a CSV will make your pump start and stop while only pumping 1 GPM instead of full pump capacity. Starting and stopping at 1 GPM is much easier on everything in the system, especially the check valve.

    Several people on this thread are pump owners that are thoughtful enough to share their real life experience on this matter. Every pump person on this thread has posted their name, web page, and or contact info. You could easily pick up the phone and call any of us for advice. They are not hiding behind their anonymity, what about you?

    If you believe that manufactures are making products to last and not just to make money, then I have some land in Louisiana I would like to sell you.

    I have studied in great detail, velocity, check valve designs, operating speeds, and other things. That is WHY I know that none of this matters if you have multiple check valves working against each other.

    I only censor false or misleading information about pump systems, to try and lessen the confusion for readers. This subject is already confusing, without any misinformation. Maybe we would get a few more pros here to discuss such things, if their every reply was not being constantly refuted as having purely self serving commercial motives. Comments from people who have a pump or two of their own is greatly appreciated. However, those who have sold, and then had to stand behind, many different brands of pumps and equipment, have knowledge that cannot be learned from any school or books. As with any subject, information from people with actual experience with the products and methods available should be highly regarded.
  20. valveman

    valveman Moderator Staff Member

    Messages:
    4,549
    Location:
    Lubbock, Texas
    The mass of the water is another reason WHY you do not want multiple check valves in a system. Multiple check valves separate the column of water into more than one mass. When the pump starts, these masses collide with each other and causes water hammer. One check valve, one mass of water, nothing to collide into. As long as you start and stop this mass of water smoothly, no water hammer.

    Goulds probably doesn't even know that they still refer to Flomatic check valves in their old manuals. This is further proof that their manuals are out of date. Also Goulds is one of several pump companies who has done extensive testing of Cycle Stop Valves. I know this because I supplied them with the valves and answered their technical questions several years ago. I could never get the results from their test. However, you will not find any directives in their literature warning against the CSV. They also do not disallow warranties on their pumps when used with a CSV. This is all the proof you will get from them that the CSV is a good thing. What you won't find written officially from them, is the fact that they found that the CSV makes pumps last longer and uses smaller tanks. If greed has nothing to do with it, then they should be recommending products and methods that make pumps last longer. When pig's fly!!
Similar Threads: Check valve
Forum Title Date
Pumps and Tanks Well Forum & Blog Adding a New Check Valve at the Tank Level Jul 27, 2014
Pumps and Tanks Well Forum & Blog Bad Check Valve? Pressure tank drains during power outage. Apr 18, 2014
Pumps and Tanks Well Forum & Blog Where would the leak happen related to the check valve? Mar 26, 2014
Pumps and Tanks Well Forum & Blog check valve on submersible and pside kick? Mar 14, 2014
Pumps and Tanks Well Forum & Blog check valves for water storage tank Jan 14, 2014

Share This Page