Banging pipes when well pump kicks on

Discussion in 'Pumps and Wells' started by wingnut225, Jul 28, 2012.

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  1. Jul 28, 2012 #1

    wingnut225

    wingnut225

    wingnut225

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    Hi,
    I have a well pump and whenever the pump kicks on, the water supply line (PVC) in the basement that leads from outside to the tank will make a loud bang noise. This occurs at a 90 in the line. I thought it might be air in the line as if the foot valve at the well pump is bad but I don't get any air come out when I turn on the faucets. I have researched "water hammer" but that mostly refers to when a faucet is turned off. How do I remedy this? Most annoying plus I don't want my PVC water line break.

    Thanks!
    Chuck
     
  2. Jul 28, 2012 #2

    spyshot

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    check valve?
     
    Last edited: Jul 28, 2012
  3. Jul 29, 2012 #3

    orlandosterilizer

    orlandosterilizer

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    I have encountered this before (im a state certified florida master plumber of ten years) and the remedy is usually to place the bladder or hydro-pneumatic tank directly adjacent to the supply well pump with as little turns in the the pipe as possible. Doing this will give lots of expansion for in incoming rush of water wich exerts many pounds of force in the pipe fittings leading to failure.
     
    Last edited by a moderator: Jul 29, 2012
  4. Jul 29, 2012 #4

    speedbump

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    Wells & pumps; not a... Professional

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    What kind of pump do you have? A submersible or a jet?
     
  5. Jul 29, 2012 #5

    Valveman

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    Remove any check valves above ground. The “foot valve” is the only check valve you need in the system. Then if as you suspect the foot valve is bad, the pressure will drop and the pump will start up even though you are not using any water in the house or yard. The above ground check valve is masking the problem at the moment, but it is also causing the water hammer on pump start. Replacing the foot valve is usually the only way to solve this problem.
     
  6. Jul 30, 2012 #6

    speedbump

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    Wells & pumps; not a... Professional

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    This made me wonder just what the heck was going on, so I'm trying to figure out if you have a sub or a jet. Foot Valves are not at the pump. They are in the well. Some people think submersible pumps have Foot Valves.
     
  7. Oct 25, 2012 #7

    teganiqbal

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    We have a well, not public water. Several seconds when the regulator tells the well pump to kick on, our water pipes bang. What are the causes for this banging and how can it be stopped?
     
  8. Oct 25, 2012 #8

    speedbump

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    Wells & pumps; not a... Professional

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    Like mentioned above. Remove any above ground check valves.
     
  9. Apr 30, 2014 #9

    wingnut225

    wingnut225

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    It's been a while but I wanted to post the fix in case anyone in the future has the same issue.

    I had a plumber check the well and indeed, the check valve or foot valve was bad. Strangely enough, I wasn't getting any air come out when I would turn on the faucets. Since he had the 17 year old pump out of the well, I had him replace the well pump along with the check valve. It's been almost two years now and all is good. No more banging of the pipes!

    I appreciate all of your thoughts and comments!

    Chuck
     
  10. May 1, 2014 #10

    Valveman

    Valveman

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    Thanks for the update. The check valve at the bottom of the well must be fixed or replaced to stop this kind of water hammer. Sometimes just removing the above ground check valve makes the bottom check work and solve the problem. In many states an above ground check valve is illegal, as it can potentially draw contamination into the well. Other states have not figured that out.

    In Texas they say you must have a check valve above ground, but you cannot cause a negative pressure on the underground line. This just shows how little our government officials understand about their jobs. An above ground check valve CAUSES negative pressure on the underground line. So you can’t have it both ways.

    Most people just put a second check valve as a “safety” for when the bottom check fails. What they should be doing is eliminating the pump cycling, which is what causes check valves to fail. Glad you got it fixed, but if you still have an above ground check valve and your pump is still cycling on/off repeatedly, you will soon have the problem again.
     

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