Way high PSI woes

Discussion in 'Irrigation' started by BPS##, Sep 1, 2012.

  1. BPS##

    BPS## LawnSite Senior Member
    from WY
    Posts: 828

    So one of my apartments (first year contract for me, 15 yr old property) had 135/140 psi at the backflow. Soon as I realized this I immediately put in a request for a pressure regulator. Bid was approved and installed.
    Prior to this we'd get leaks and breaks that were pretty obvious it was from high PSI water hammer on the lines.



    Now that the regulator has been in I'm changing out A LOT of formerly working heads. 2 cases of RB 5000s and counting, in just one month.
    Whats the deal with this? Any body else run into a similar situation?


    The best I can come up with as to why they were working and now they aren't is from my help. He wondered if the pressure was so high that it forced a lot of sand/grit past the filters and even tho it was gumming up the works the super high pressure kept the heads working. Now that the pressure is back to more manageable levels the heads just won't work.


    Thoughts????????
     
  2. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 47,008

    What nozzle pressures are seen at the bad heads?
     
  3. BPS##

    BPS## LawnSite Senior Member
    from WY
    Posts: 828

    I should have known you'd ask that. I don't know.

    More than enough to push the spring up and spit water the same distance as heads beside them that are working.
    A pinched swing line going to the head doesn't make sense on 40 some heads.


    This is not a problem on one or two zones that the all the heads don't work. Its across the entire 180,000 sq ft.
     
  4. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 47,008

    Buy a pitot adapter for a pressure gauge. Take some measurements before applying any system remedies.
     
  5. CAPT Stream Rotar

    CAPT Stream Rotar LawnSite Fanatic
    Posts: 5,895

    flow control valves?
     
  6. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 47,008

    All rotor heads have bearings, and high pressure can't be any great benefit to them. Maybe overpressure wears bearings, and increases bearing friction. Reducing pressure would then reduce the forces that rotate the head, possibly to a point of non-rotation.
     
  7. CAPT Stream Rotar

    CAPT Stream Rotar LawnSite Fanatic
    Posts: 5,895

    I'm on a few systems with 70+ psi and every year we are changing 10 + pgp's..

    Pita
     
  8. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,799

    I'm sorta leaning that way. The high pressure wore the original bearings out, and ,when the the pressure was reduced, guess what? The system was over- zoned and failed. :dizzy: I have no problems with rotors at 90 psi, but the design must reflect it. :)
     
  9. AI Inc

    AI Inc LawnSite Fanatic
    Posts: 25,236

    The system was designed around what was there. Now that psi is reduced it is prolly below working pressure in some areas.
     
  10. Irrigation Contractor

    Irrigation Contractor LawnSite Senior Member
    Posts: 380

    What did you set the PSI at with the new regulator(s)? In your case we would use a Wilkins 600 HR rated for 75 - 125 PSI and knock it down to 85 or 90.

    We have a maintenance project that is very close to what you have going on. We can run 1 or 2 zones at a time with no trouble, the we need to run 3 - 4 to meet the managers (Multi- Family Community) water window expectations.

    We still blow mainlines, but now it is due to try to push more gallons through a mainline never designed to handle that amount. I have been telling then we need another water source, then isolate the entire property into 3 smaller systems. This way we can drop the pressure down into the 80's.

    Good luck and I know how frustrating it can be, but the best way to cover yourself is with great communication and data to back it up.
     

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