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Rainbird 5000 Rotor Nozzle Selection

Discussion in 'Irrigation' started by RCDuck, Aug 1, 2008.

  1. RCDuck

    RCDuck LawnSite Member
    Posts: 6

    I'm not an irrigation professional... just a homeowner looking for a little advice on my system.

    I recently built a new home on o 1 acre. The home included an irrigation system installed by my builder's designated irrigation sub. For the most part, I think the system is adequate, but one thing that they did that doesn't make sense, is they installed the #3 nozzles on all of the rotor heads regardless of the arc pattern of the head. If my zones were laid out by arc pattern, I can understand how this could be workable by adjusting run times, but I have zones that are a mixture of arc patterns. For example, one zone has 2 full circles, 2 half circles, and 1 quarter circle. Why would I have the same nozzle on all of these heads?

    The first thing I tried was the 30' MPR nozzles. I installed the F(ull), H(alf), and Q(uarter) nozzles accordingly, but it appears that the precip rate of the MPR nozzles is too high for what appears to be marginal pressure. The 30' full nozzles were only throwing about 22'. I hooked up a pressure guage to one of the head outlets and was reading about 30 psi when the zone was running.

    My next plan is to go back to the standard blue nozzles which can have a lower precip rate, but selecting the nozzle #'s based on arc pattern. What would be a good starting point for nozzles for a mixed arc zone? My plan was to try the 1.5, 3, and 6 nozzles on the quarter, half, and full arcs respectively. Does that stand a chance of getting something workable as far as precip rate and throw distance?

    Any advice is appreciated. I apologize in advance for being a homeowner meddling in the art/science (Which is it?) of irrigation, but I think I have a better chance of getting it the way I want it than trying to explain it and getting it implemented by my builder's selected irrigation contractor.
     
  2. AI Inc

    AI Inc LawnSite Fanatic
    Posts: 25,151

     
  3. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,599

    It very well could be you are overzoned. Try the blue nozzles, is there a way you can
    measure the pressure while the zones are running?
     
  4. RCDuck

    RCDuck LawnSite Member
    Posts: 6

    Excuse my ignorance, but by overzoned to you mean too many heads on each zone?

    As I stated above, I did install a pressure guage in place of one head on the zone and measured 30 psi while the zone was running, but I guess that probably isn't completely accurate since there was one less head operating on the zone than there is when the head is in place instead of the pressure guage.
     
  5. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,599

    Yes, I wonder if the system ever worked properly; most of us have not had
    good luck with builders because they're usually out of money when it's
    our turn. At 30' spacing, how many heads do you have on each zone?
     
  6. RCDuck

    RCDuck LawnSite Member
    Posts: 6

    5 heads max... some zones have 4
     
  7. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,599

    W, with four heads, MPR "Green" nozzles, you are burning about 10 gallons
    per minute. You need at least 35 psi to throw 30. Using the blue nozzles
    would cut the gpm in half & getting the pressure up to where it's needed.
     
  8. RCDuck

    RCDuck LawnSite Member
    Posts: 6

    I guess that's the conclusion I came to after trying the MPR nozzles. Hopefully the blue nozzles will work for me... they did seem to have adequate coverage with #3's installed in them, they just weren't matched for arc pattern. I do have several zones that are either all halfs or all fulls, so if I need to I can just leave the #3's in them and adjust the run time accordingly.
     
  9. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,599

    The MPR nozzles are cool, but water eaters. Good luck.
     
  10. RCDuck

    RCDuck LawnSite Member
    Posts: 6

    Thank you... and thank you for the help...
     

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