The Tapering Pressure Pump Mystery

Discussion in 'Pumps and Tanks Well Forum & Blog' started by realengr, Dec 30, 2009.

  1. realengr

    realengr New Member

    Messages:
    2
    Location:
    tennessee
    Help. I have been battling with this situation for almost a half year.

    I installed a new 3/4 hp, 2 wire, 230v deep well pump last December. The unit had some issues with low flow at first but after turning it off and on a few times I had no problems.

    About 6 months ago I shocked my well with H2O2 and shortly thereafter I started having pressure problems. The pump would violently start, almost seems like water hammer, and then just hum along. I would get a burst of water pressure up to 30 psi and then it would just taper off quickly to below 10 psi. Flow is just a trickle. If I keep everything off in the house it gradually builds to 60 psi. Pump turns on back again at 40 psi but same problem.

    I even replaced the pump and put new wire and a new breaker in the box.
    Same thing.
    Specs: Well is 160 feet deep, Pump is at 140 feet deep. Water level is 2 foot from top of casing now. One check valve is in place at 40 foot down (could it be the check valve? I replaced this just 2 years ago). Torque arrestor is in place. Pressure tank has new bladder with pressure at 38psi.
    Continuity shows from each leg of pumpwire to ground. But I am getting continuity from leg to leg.
    Voltage is 115v on each leg to ground.

    Is this electrical? Is this the check valve?
  2. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    Dump the check valve, there is one on the pump.
  3. realengr

    realengr New Member

    Messages:
    2
    Location:
    tennessee
    It Works!!!!!

    Peter and Guys,

    Thanks. I removed the check valve and the unit is performing flawlessly. I wish I had found this forum 6 months ago. It would have saved me a few hundred dollars and immeasurable grief in pulling this pump about three times.

    I'm going to full pressure in seconds now and have seemingly unlimited flow.

    I am a licensed engineer and would have thought that there was no way a brand new check valve would have created this problem, but sure enough.....


    Bill Gillette PE
  4. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    Happy to have been of service.
Similar Threads: Tapering Pressure
Forum Title Date
Pumps and Tanks Well Forum & Blog Bouncing pressure switch Yesterday at 3:51 AM
Pumps and Tanks Well Forum & Blog Dielectric union at pressure tank or not ? Nov 17, 2014
Pumps and Tanks Well Forum & Blog Well Water Pressure Help Nov 3, 2014
Pumps and Tanks Well Forum & Blog Pressure dropping and climbing on pump? small crack to blame? Oct 29, 2014
Pumps and Tanks Well Forum & Blog I have a well that may not be adiquate at normal pressure. Is 20 psi enough? How about 30 psi? Oct 24, 2014

Share This Page