leak job- made a boo boo

Discussion in 'Irrigation' started by mitchgo, Jul 27, 2011.

  1. mitchgo

    mitchgo LawnSite Silver Member
    Messages: 2,956

    No pics

    After a total of 15 hours of investing time into this yard checking the water pressure should have been one of the first things to do.

    A 450' main line run on a irrigation system . I have found 5 seperate leaks in the main line ( cracked pipes and leaky fittings)

    There are at least 2 more leaks. I was curious to what the water pressure was
    so I tested it nearing the end of my time spent

    Come to find out the pressure was a 165 PSI at the back flow assembly- and the rest of the system is down hill. The valves in the back yard I could easily see being 180-185 PSI.

    Woops. A PRV Master Valve combo will now be in order. Also installing a wilkins prv prior to the Pressure compensating master valve . Your supposed to install 2 prv's in series 4:1 ratio. This will be 3:1 . Still I feel safer with both in
  2. CAPT Stream Rotar

    CAPT Stream Rotar LawnSite Fanatic
    Messages: 6,201

    how are you measuring your PSI?
  3. mitchgo

    mitchgo LawnSite Silver Member
    Messages: 2,956

    with my back flow tester kit

    120 dynamic psi o.o
  4. Mike Leary

    Mike Leary LawnSite Fanatic
    Messages: 23,171

    Can I shoot over and install some Stream-Rotors? :clapping:
  5. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,752

    don't be a piker - go for Rain Pro heads :)
  6. Buck_wheat

    Buck_wheat LawnSite Senior Member
    Messages: 585

    OK I'll bite, I'm probably the cherry here. Where the F do you get 165 PSI from? Is that static or dynamic? Is it a golf course, agriculural, a frigging fire hydrant, what?

    I service a 4" loop (about 2,500ft) serving 10 zones... my dynamic pressure is about 70-72 psi which is enough to lift all the Hunter PGP's in each zone and give me a 35" throw.

    Early on, when I started, this system had a no flow condition when a zone valve didn't open that brought static pressure to about 120, at which point it blew a fitting and I had a mountain of turf with a $hitload of water underneath it.

    I've installed a pressure relief valve and a "Hot Stop" at the pump. The relief valve is set @85 PSI (dynamic).

    I've serviced other systems, larger than this one where I have never seen dynamic pressure much over 70 PSI.

    So anybody, help me out, (this was in a guys back yard?). What was his source to get pressure readings as high as 180-185 with leaks in the line. I'm surprised it didn't wash away his mountain.

    Any way, mind you I'm just a Florida boy and not too smart...:confused: but I'm willing to learn.
  7. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,752

    elevation, dude - pump that water up to the top, and the folks lower down have pressure they wish they didn't
  8. DanaMac

    DanaMac LawnSite Fanatic
    Messages: 13,226

    We get 120-180 psi all the time on city water here. That's standard for us. Every house has a pressure regulator, but some older systems (or some rookie jackazzes) have the system in before the PRV. Quite often the PRV also fails, and then we have a high pressure problem. We replace about 10-20 PRVs a year. We did one just yesterday.
  9. Buck_wheat

    Buck_wheat LawnSite Senior Member
    Messages: 585

    I understand the dynamics of gravity as it relates to flow... but 165 PSI at the POC?

    I may be wrong on this, but I call bull$it on that. I've seen that type of pressure in hydrants, commercial fire systems in multi story buildings, agricultural, but a home owner?

    I'm hopeful somebody can to explain to me where 165 psi comes from at the POC and not do some damage to a residential irrigation installation, never mind the 185 psi at the heads on the bottom of the hill.
  10. DanaMac

    DanaMac LawnSite Fanatic
    Messages: 13,226

    As I mentioned, our 120-185 psi is static. SOP here. Don't call bull$hit just because you haven't seen it.

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