Shallow Driven Well and Air Leak

Discussion in 'Pumps and Tanks Well Forum & Blog' started by Wallysurfr, Apr 24, 2013.

  1. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    Type of pump?
    Jet Pump (above ground): Flotech 1/2 HP Shallow Well Jet
    One or two pipes down the well: 1
    Pump Model # FP 4012
    Date Pump Installed: 4/20/13

    Pumping from?
    Water Well
    Depth of well: 36" screen point at 18'
    Depth to water: ~10'
    Pipe Size 1.25 Galv Steel"

    Well Recovery Rate: 3 gpm
    Well Casing Diameter: 3” down 10' to make driving easier
    Sandy Soil
    Date Well Drilled: October 2012

    Well Casing Material
    3" PVC down 10' and 1.25" galv steel down 15' with 3' stainless screen

    Pressure Tank? NO

    Pressure Switch Setting? NA pump shuts off at 70 psi

    Pump Control Method?
    Manually turned on and off

    Pump Protection
    Other built in shut off at 70 psi

    Filters or Softeners NA

    Water Used For?
    Irrigation with hoses for now and would like in ground sprinklers

    Problems Experienced:
    Low flow
    Air in water

    Do you have, and know how to use
    an Ampmeter and Voltmeter: yes

    Describe Problem: see below:

    Let me first apologize that my first post is a new thread but I have noticed that when I ask google a question about my situation this site almost always gets the top hits.

    I just read the sticky by speedbump in the shallow well forum and already learned more than I had in the past 8 months.

    Let me make a long story well… long…

    I live 1.5 miles from the beach in NJ. My dad and older brother put a well in at his house about 30 years ago (driven galv pipe) it sat for about the past 20 years, they recently hired a sprinkler guy to tap their city water and he found the well primed it and it worked perfectly. He plumbed it to sprinkler system and free water! This prompted me to put my own well in.

    So, I found a website that recommended a water jetting method so I decided to give it a try. I want a nicer lawn and my water bill gets too high in the summer because of the sprinkler. I also wanted a source of free water on my property (small at 50’ x 100’). My soil ended up being too sandy for the jet method so the water w/ clippings wouldn't come back up it would just wash down.

    So I used a shop vac to get down to the water table @ 10' (I thought I was the genius who thought of this) and now I see others have been doing that for years.

    I dropped a 3" casing down the 10' vacuumed hole to keep it open.

    I got a 36" stainless mesh screen (water source brand), a 10' section of 1.25” galv pipe, 2 sections of 5' galv pipe, drive couplings, drive cap etc.
    I made the mistake of using the sledge hammer (as I read in the sticky) plus I'm not sure (can't remember) if I drove each coupling all the way home so I’m thinking the one coupling that is above the water table may be leaking air. I may have also loosened the couplings by using the sledge although I did give the pipe a couple turns in between hits and used a sacrificial nipple with drive cap. There was no damage to the threads at the top of the pipes. Right now the point is at 17' 6" with the water table at 10' so there's 4'6" of water above the top of the screen.

    Then I started plumbing to the pitcher pump for well development. I installed a vertical brass check valve, a T and valve for priming below the check valve and the pitcher pump. The problem is I hadn’t researched about reducing the number of connections so I had a total of 11-12 connections between the water table and the pitcher pump (I know)… this number goes to 17-18 once I attach the jet pump.

    So last fall, I pumped the pitcher for maybe 4 hours total trying to develop it. I would always get kick back on the handle and it seemed the water wasn’t recovering fast enough and there was vacuum created in the line which would make the handle hard to push down (pulling the plunger up and water out). I figured I had to “develop” it. So I pulled the plumbing off the top and used the “drill head” that I made for the washing method to attach my hose to and flush water down the well. I also bought an oatey clog buster and put that down to try to wash sediment away from the screen. I've done this 4-6 times now.

    A couple days ago I decided the water was clear enough to put the jet pump (1/2 hp) on and start pumping so I did and I got about 1.75 gpm with air bubbles in it. I shaving creamed all the above ground joints and saw the union and the connection at the pump were sucking air. I tightened them up, re-primed and got a little over 3 gpm still some bubble in it. As of right now I have pumped about 1000 gallons out.

    So that’s where I am at. Currently, I am planning on pulling the prime valve, and above ground plumbing and resetting all the joints tight with pro dope (and teflone tape?).

    The weird thing is the well (pre check valve) holds prime as far as I can tell. The pump (post check) holds water when turned off, no drips from where I know there were air leaks.

    If I still have bubbles, I am thinking of ordering a few internal 1” slip PVC couplings and transitioning over to PVC with the most limited number of connections I can have. That number is 8 including the slip half way down (2), the priming T and plug (3), check valve (2) and pump (1).

    I don’t think I would be able to pull the pipe out to reset the joints. I don’t have a “come along”.

    Here are my questions:

    1. Do you guys recommend Teflon tape and dope or just dope?
    2. Can I put 1” PVC w/ internal couplings (assuming it will fit) down the galv pip like a straw in order to eliminate the under ground air leak?
    3. Could the water just be oxygenated?
    4. Will 1” PVC inlet give me enough flow to power 2-3 sprinkler heads? (Pump is 1.25” inlet 1” outlet)
    5. Can I expect to get the same 3 gpm with the reduced pipe inlet size?
    6. How bad is an airleak on well production? If I eliminate it can I expect 4 gpm?
    7. Are 1.25” galv unions known to air leak?
    8. Would you say my leak is pre or post check valve? (really hoping its above ground)

    Wish I had posted here last fall when I started this project. Probably would have saved some money. Right now, I’m into it for about $400 includes the $150 pump. Not bad for a water well compared to $4,000 for a driller but I have a lot of time into it and it’s not where I want it yet.
    Any input is appreciated!
    Last edited: Apr 24, 2013
  2. valveman

    valveman Moderator Staff Member

    Messages:
    4,583
    Location:
    Lubbock, Texas
    I really don’t think you have a suction leak because you are not completely losing prime. My guess is the formation is just tight, and the 3’ screen will only let in about 3 GPM. So you might have to drive a couple more well screens and tee all three together before the pump to get 9 GPM.
  3. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    Thanks Valveman!

    would the air bubbles be a symptom of a tight formation?
    will the formation loosen over time w/ pumping?

    The way I have my zones setup, I don't need more than 3 gpm (yard is small), will the sprinklers work with the air in the line or will they spit?

    I think I could put another pipe down, now that I have a proven method but would rather not (maybe next year).

    Thanks again for the response. I have learned a lot doing this and hope to continue to learn and maybe even put some in for other people.
  4. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    Thought of a couple more questions:

    1. Would a pressure tank solve this problem?
    2. Will I destroy the pump with a small amount of air in the water? I have felt the pump after 3 hours of pumping and the wet side is not hot at all, water never gets hot either.
  5. valveman

    valveman Moderator Staff Member

    Messages:
    4,583
    Location:
    Lubbock, Texas
    Even if you do not have a suction leak, trying to draw more water than the well can produce causes cavitations. It is basically sucking so hard it pulls the air out of the water itself. These air bubbles implode inside the pump, and the damage makes worm-hole like patterns, and greatly shorten the pumps life.

    Now if you restrict the flow on the discharge side of the pump, like only having 3 GPM worth of sprinklers attached, cavitations do not happen. But you have to restrict the discharge flow to the same or less than the amount the well can produce.

    No a pressure tank won’t help anything, and you only need to be letting out about 1 GPM to keep the pump from getting hot.
  6. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    Sick! I will make more zones w less heads per zone so I'm never trying to flow more than 2-3 gpm. Maybe as the well pumps and continues to develop the air will go away.

    I'm going to design a test. Hook up the sprinkler head w/ 1.36 gpm and stick the head under water and see if I get air. Then add another head to see at what point I get air.

    The physics involved with this are much more than I ever thought. Atmospheres, cavitations etc. Pretty sweet!
  7. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    5 points for every answered question. So far, valveman is in the lead...

    1. Do you guys recommend Teflon tape and dope or just dope?
    2. Can I put 1” PVC w/ internal couplings (assuming it will fit) down the galv pip like a straw in order to eliminate the under ground air leak? A: Wallysurfr, yes
    3. Could the water just be oxygenated? A: Valveman, no it may be cavitating due to low supply
    4. Will 1” PVC inlet give me enough flow to power 2-3 sprinkler heads? (Pump is 1.25” inlet 1” outlet)
    5. Can I expect to get the same 3 gpm with the reduced pipe inlet size?
    6. How bad is an airleak on well production? If I eliminate it can I expect 4 gpm?
    7. Are 1.25” galv unions known to air leak?
    8. Would you say my leak is pre or post check valve? (really hoping it's above ground)
    9. Would the air bubbles be a symptom of a tight formation? A: Valveman, yes
    10. Will the formation loosen over time w/ pumping?
    11. Would a pressure tank solve this problem? A: Valveman, no
    12. Will I destroy the pump with a small amount of air in the water? A: Valveman, no as long as you have 1 gpm

    Now, who wants some points?
  8. valveman

    valveman Moderator Staff Member

    Messages:
    4,583
    Location:
    Lubbock, Texas
    I don’t know how I would spend the extra points. J But I will try to help anyway.


    1. Teflon first, then dope over that.
    2. Yes, but I do not think you have a suction leak.
    3. No
    4. Yes
    5. Don’t need very large pipe for just 3 GPM, so yes.
    6. I think an air leak would cause you to lose prime, not just have air in the water.
    7. Yes
    8. No leak, I know you want it to be a suction leak, but it is a low producing well.
    9. Again yes.
    10. No
    11. Again no.
    12. Not what I said. 1 GPM is all you need to keep the pump cool. But air bubbles at any flow rate will implode in the pump causing wear from cavitation.
  9. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    ok thanks! So I won't burn my pump out from heat but will cause the worm hole type damage on the impeller? I know it probably depends on the degree of cavitation but about how long do you think the pump will last? Hopefully the issue will be fixed once I get some restrictors (sprinker heads) on the end of the pump side.

    By the way, thanks a lot for paying attention to this thread. I know people like you probably give away $100's of thousands of dollars worth of information on forums and rarely get a genuine thank you. So, thank you! After all of my thinking, researching and wondering over the past 8 months I have learned more and gotten more questions answered here in the past few days.

    You win all available points (60).

    Regular Teflon tape (white stuff) or the heavy duty blue? Pro Dope alright?

    Is there a way to make sure i'm not losing prime? Just let it sit like 24 hours with check valve on it then open the priming port (below check) and see if it sucks down?

    Thanks again!
    Last edited: Apr 25, 2013
  10. valveman

    valveman Moderator Staff Member

    Messages:
    4,583
    Location:
    Lubbock, Texas
    Sprinkler head...ding, ding, ding! Put on a 2 GPM sprinkler and see how it works.

    Regular Teflon is OK, I like Rector Seal dope.

    If you were losing prime, the pump would just stop pumping instead of just producing air bubbles.

    Thanks for the thanks! As they say at the Rodeos here when the Cowboy gets bucked off, "thanks for your applause as that is all he gets to take home tonight".:)
  11. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
    Yeah I wish I lived in TX. Too bad I'm stuck in a nanny state (for now).

    Is there some kind of throttle valve I can install on the pump side to make sure it doesn't try to draw more than the well can give? I read a little about it in another thread.

    Would going deeper (I have another 5' threaded galv pipe) possibly fix this problem?
  12. valveman

    valveman Moderator Staff Member

    Messages:
    4,583
    Location:
    Lubbock, Texas
    Going deeper could make it better, but it could also make it worse. The idea is to get the screen in the water-bearing zone, no matter where that is. If the water-bearing zone is deeper, adding more casing will help. If the water-bearing zone is shallower, adding more casing will make it worse. Adding more screen would be better. 6’ of screen has a better chance of being in the right place than 3’ of screen. Sometimes the extra screen can be added in the same casing, sometimes several wells, each with its own 3’ of screen is better.

    Just use a brass ball valve for throttling. If you get the rate you need figured out, then you can order a Dole valve set for that amount.
  13. Wallysurfr

    Wallysurfr New Member

    Messages:
    11
    Location:
    Wall, NJ
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