Fimco-meister need pump meisters

Discussion in 'Irrigation' started by FIMCO-MEISTER, Sep 7, 2007.

  1. I can't find the original thread so here goes.

    I have an existing system on a 5hp pump that looks like it was originally a city water system that got converted. The pump has croaked from repeated flooding and needs to be replaced and moved to higher ground. The new pump will be located 13' above the creek and will be 40' in fed by 2" pipe. The mainline is 1 1/2". Still a dinky pipe system but for me this is a massive giant job.:)

    To keep the yard alive I disconnected the pump line and re-hooked the system to the water meter. This also allowed for gallonage readings. Half the zones are pgps so I'd like to have 55psi at the pgps.

    Here are the zone gpm readings 20 total stations

    1. 32gpm spray 2. 18gpm spray 3. 26gpm spray 4. 10gpm pgps 5. 20gpm spray 6. 18gpm pgps 7. 26gpm spray 8. 44gpm tree bubblers 9. 22gpm pgps 10. 22gpm pgps 11. 28gpm pgps 12. 34gpm tree bubblers 13. 18gpm spray 14. 32 gpm spray 15. 24gpm spray 16. 36gpm pgps 17. 30gpm pgps 18. 38gpm pgps 19. 26gpm pgps 20. 38gpm pgps.

    I have attempted this myself but I'm withholding my results since posting those would cause us to spend way too much time I'm why I'm a numb-skull.

    Thanks
    peter
     
  2. 55 psi is 127.05 ft hd right?
     
  3. Also the system is uphill from the pump. Max I'm guessing is 8'. Furthest head/rotor 250' from pump.
     
  4. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 48,035

    How fixed are those flow rates? Since PGPs can be renozzled, and bubblers exchanged, the flows might be brought to 20 gpm or less, and you could use a Goulds J15S ~ I like their jet pumps, and would go a ways to have a system that a J15S could supply.

    The next step up is a multi-stage centrifugal from Sta-rite (Berkeley) http://www.starite.com/specs/berk_b2094bk.pdf Bigger case, inlet and outlet, raised suction to help hold prime. This pump is a better fit for the 30+ gpm flows you mentioned. I've never used this 4-stage centrifugal, so I don't know how reliable it is. The performance curve exceeds that of a Goulds 2 HP multistage centrifugal. For a 40 foot suction line at 30+ gpm, with a foot valve, there might be some sense to using a larger suction line than 2-inch, but you're probably okay with 2-inch.
     
  5. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,308

    I would have to agree with regard to getting the flow rates down. Take a good look at what can be done to achieve that, pick an achievable target GPM based your pump of choice sweet spot.
     
  6. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,308

    1 foot of head = 0.433 psi for a column of water

    Or more simply put you lose or gain 0.433 psi/ft of elevation change.

    55 psi = 127.02078521939953810623556581986 feet of head :)
     
  7. drmiller100

    drmiller100 LawnSite Senior Member
    Posts: 562

    dude,
    reread my comments. they still are right. The pump WANTS to pump 70 gallons per minute.
    if you don't let it pump as much water as it wants, you are going to have huge amounts of noise and burn your pump up quickly and waste a bunch of water and piss everyone off cuz the pump is noisy.
    70 gallons a minute through a 2 inch suction line is a JOKE. Sucking oatmeal through a straw and wondering why you are hungry.
    pushing 70 gallons a minute through a 1.5 inch pressure line is likewise a joke. also really bad is how you neck hte pipe down right out of the pump.

    Also, you only have 2 acres and are thinking you have 44 gallons of bubblers per minute. i wonder instead of it is really 44 gallons per hour????
    In any case, consider strongly getting a more reasonable pump. It seems to me that if you had 35 gallons per minute, you would have enough water for the biggest zones excluding bubblers. Bubblers will work wiht very low pressure, so I will totally believe the 35 gpm would push the 44 gpm needed for the bubblers.
    So, if you are looking at a smaller pump, I would guess 3 horsepower. I would guess that would get you close to 35 gpm at 50 psi, but you need to check my math.
    From there, start wiring valves together to get them to add up to 35 gpm, or something kind of close.
    wire zone 2 and 5, both sprays, gets you to 38.
    4 and 9.
    5 and 13

    consider renozzling one of hte zones, or do something to get zone 6 up over 30 gpm so the pump runs efficiently.

    When running valves together, test them. Run zone 2. turn on zone 5 manually, scratch your head, and figure out if they can run similar times based upon sunshine, coverage, nozzles, etc.

    1. 32gpm spray 2. 18gpm spray 3. 26gpm spray 4. 10gpm pgps 5. 20gpm spray 6. 18gpm pgps 7. 26gpm spray 8. 44gpm tree bubblers 9. 22gpm pgps 10. 22gpm pgps 11. 28gpm pgps 12. 34gpm tree bubblers 13. 18gpm spray 14. 32 gpm spray 15. 24gpm spray 16. 36gpm pgps 17. 30gpm pgps 18. 38gpm pgps 19. 26gpm pgps 20. 38gpm pgps.
     
  8. Thank you Dr Miller. Yes it is 44 gpm but coming from the meter at 70 psi. Don't chomp my head off but is it 35gpm with 50 psi at the pump? Meaning that by the time the water molecules traverse the ups and downs and lefts and rights that I will only have 40-45 at my pgps? Looks like I really need to nozzle my pgps down some. I had figured 3 hp but these folks were sold a 5 hp by a pump expert that croaked (not the expert). This is the first pump job I haven't run from and that is cuz I trust the forum advice.
     
  9. drmiller100

    drmiller100 LawnSite Senior Member
    Posts: 562

    ok, so lets try a test with what you've got.

    run a zone. now manually turn a valve or 2 on, and watch what happens.
    40 psi at the pgp is a GREAT plenty, and in fact many pump systems won't really provide that. the real question is whether you get head to head coverage, and can you fix it if not.

    if your main line is big enough given the pump you have, you should be able to run 2 or 3 valves at one time, and actually EXPECT more pressure at the sprinkler head. Why? Because your pump is so far out of its happy zone, it is thrashing.
    however, it is entirely possible your 1.5 inch main line is not big enough. can you run anohter 1.5 main line into the other end of hte valve box?

    do NOT nozzle down and expect better results. you might get somewhat better results for the short term, but in reality you are actually tearing up your expensive pump even faster.
    finally, the suction line. it goes into the pond. What is at the end of the suction line? does it restrict flow?????
     

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