Need help with sprinkler system and a well

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  #1  
Old 07-21-11, 05:40 PM
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Need help with sprinkler system and a well

I bought a house with a sprinkler system already in it but it doesnt work. The sprinklers go like gangbusters for a few minutes the fizzle out. Is my well running out of water or is it my pump not pumping enough.
 
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  #2  
Old 07-22-11, 03:19 AM
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Is the sprinkler system on the same well as the house? If so then try turning on a faucet or garden hose when the sprinklers have fizzled out and see if you get water.

When the sprinklers fizzle out has the sprinkler controller told the sprinklers to turn off? Is it possible you are just seeing the normal shutting down of the sprinklers? When sprinklers turn off sometimes they can dribble water for some time.
 
  #3  
Old 07-25-11, 07:58 AM
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I am turning them on manually. They go good for about 5 minutes, then petter out. There are 3 sprinklers per line and im trying one line at a time.
 
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Old 07-25-11, 08:41 AM
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What happens when you turn on a faucet at the same time you're running a sprinkler (as Dane asked)?
 
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Old 08-01-11, 10:06 AM
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This is what i think is happenening ( I just dont know how to fix it) I think that when i turn on the sprinklers the pressure in the lines/tank is at its highest, maybe 50 to 60 psi, when i turn on the sprinklers the pressure is good enough to run the sprinklers for a few minutes untill the pressure drops to what just what the pump can put out, about 40 psi ( I am going off the guage on the port on the pump itself, not on an inline gauge if that matters.
So is it just a matter of the pump not being big enough? or is the a way to make the pump run at a constant 60 psi??? I dont know anything about pumps or how they work. I did notice that the pump can run at 110 or 240 i think and i was gonna make sure it is hooked up to 240 but i dont know if that even matters.

BTW if i turn on a faucet while the sprinklers are on they will have the same behavior as the sprinklers. Good at first then less. It doesnt seem like the well runs out of water, just pressure.
 
  #6  
Old 08-01-11, 11:37 AM
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You can look at it one of two ways. You are either drawing too much water or the pump is too small. You can change the nozzles/heads on your irrigation system to reduce the flow or you can break it up into more zones so it does not take as large a volume of water. Or, you can go to a larger pump that is able to supply the higher pressure you want.

Many irrigation systems work to reduce the pressure and do not run at 60psi. At that high a pressure you get a lot of misting/fogging which wastes water. With a lower pressure the heads can produce a larger droplet size the is blown around by the wind as bad and the larger droplets don't evaporate as badly while flying through the air.
 
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Old 08-01-11, 12:11 PM
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Hi,

Pilot dane is correct. I will try to add more info for you.

1. First qustion I have is did this sprinkler system ever work correct, or has it always been this way? Who installed it?

2. Regardless of the above the first thing you want to do is find your gpm. Fill a 5 gallon bucket from a outside hose bib and time how long it taks to fill almost to the top. ( A 5 gal bucket holds more then 5 gal.)

Make sure the pump kicks on and is running when you do this test. Also try to start the test when the psi is sitting at 50 psi, pump running.

Divide 300 by the number of seconds it takes to fill 5 gallons into the bucket to get the GPM. (300 / seconds to fill 5 gallon bucket = GPM) Example: 10 seconds to fill the 5 gallon bucket, therefore 300 divided by 10 seconds equals 30 GPM.

3. Once you get gpm then you need to go to each zones sprinkler head and find what size nozzle is on there. If you give the name and type of the head and any info you can I can help you with that.

So say you find you have 5 gpm. Then if you have 3 heads on each zone you will want the nozzles to be about 1.5 gpm each. This should let your pump keep up and run around 50 psi. You want to set it so the pump never turns off while the sprinkler is running.

A example of mine is a 5gpm well. I have 10 zones. One sprinkler per zone. All rotor except one zone has 6 sprays. Each head has a 4 gpm nozzle. My psi sits at 52 psi with the sprinkler on. The 6 sprays I have a .45 gpm head on each. Comes close to 4 gpm. This allows my pump to run and never shut off. If I tried to turn two zones on the pressure will slowly go down continually until the a trickle out the heads.

I of course can put nozzles at 2 gpm and run 2 heads at a time but found a slight breeze blows the stream all around. I rather dump as much water as I can with one head at a time. Waters better IMO. Plus the one 4 gpm nozzle shoots farther for how I have them set head to head coverage. If I put the less gpm nozzles I would need to space them closer and use more heads. I hand dug it. I was not putting in anmore heads then I had to.

So you see its complicated but is easy once you understand it.

Let us know.

Mike NJ
 
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Old 08-01-11, 09:45 PM
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Thank you for all the great info.

First off i do not know if the sprinklers ever worked correctly. I am gonna assume they did. I know before we bought the house at some recent time the pump was replaced. I was wondering if they didnt just buy a cheap pump since they were selling the house.
I will look at all my sprinklers and try to see what gpm they are, as well as do the bucket thing and get back to you.

Thanks
 
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Old 08-02-11, 03:24 AM
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Do you know what brand sprinklers you have? Are they impact, rotators or spray heads? If you look very closely can you see numbers on the spray heads or are they different colors?

Identifying what you have will help determine the water volume you need to provide.
 
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