# Large Yard - inefficient sprinkler placement



## racng69 (Mar 21, 2020)

Hello All,

I have a 30k yard with what i believe to be an inefficient sprinkler head placement. Along the walk ways and driveways i have spray heads and in the middle of the yards i have 360 degree rotors. the yard is getting too much water near the walkways and driveways because in order to get 1" of coverage in the middle of the yards i am having to run each zone double the amount of time.

Unfortunately each zone has a mix of some sprays and rotors. If i cut back the sprinkler timer for each zone, then around the walkways and driveways are good but brown in the middle of the yards.

So, after summer we will p split up each zone into rotors and spray heads to alleviate this issue, however in the mean time is there a spray head that will shoot 30-40 feet? so that we can get adequate coverage in the middle of the yards?

We are getting alot of dollarweed due to the over watering in those area that dont have the 360 heads.

Or maybe there are faster 360 heads that will work better. It is a mixture of K-rain pro and rain birds 3/4 inlet size.


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## MrMeaner (Feb 21, 2017)

Most rotors you can change the nozzle size. If I have a rotor in a 90 degree corner I use a smaller nozzle like a 1-1.5GPM, a 180 degree head will get a 2-2.5GPM head and anything doing 360 gets a 3-4GPM nozzle. Adjust nozzles to go head to head for the best coverage. What I did was map out my whole system and zones and made sure I had enough pressure to run the larger nozzles. Once I was finished changing out all the nozzles I did the tuna can test to see how much water was being put down in each zone and adjust watering times accordingly.


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## jht3 (Jul 27, 2018)

Bad design to have sprays and rotors in the same zone. As you are discovering they put out water at very different rates.

What brand rotors and sprays? You might be able to swap the spray internals for rotators, which have a precipitation rate more similar to rotors.

Also, check which nozzles you have installed.

My Rainbird 5004 rotors can easily shoot 30+'.


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## racng69 (Mar 21, 2020)

i can replace the sprays with rotors, no problem. but i think i would still have too much water, since the ones that are 360 degrees would take twice as long to get the same coverage as a 180 degree rotor? is that the correct thinking?

i have about 30 PSI on this zone. the other two zones have almost 40 PSI.

its a mix between rain bird and k rain sprinkler heads. i changed one of the nozzles in one, and that one seems better. but i wonder if i will have enough PSI to do that in all the 360 degree heads.

Another option i suppose to is if i add rotors, i may be able to cap off a few of the places where the sprayers were. thoughts?


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## Vtx531 (Jul 1, 2019)

As you discovered, you need to change nozzle sizes. 180 degree headshould be twice as much flow (gpm) as a 90 degree head. And 360 degree head should be four times the flow of a 90 degree.

You don't need to worry about pressure as much as flow capacity. Pipes can only reliably handle a certain GPM total flow (add up all the heads based on nozzle size chart). As you increase GPM, the velocity of water in the pipe increases.

3/4" copper pipe you can go up to about 10 gph without being too excessive. This means only one 360 rotor and a couple 90 degrees rotors is about the most you can put on a single zone. Refer to the specific manufacturer nozzle charts to be sure.


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## bernstem (Jan 16, 2018)

Try to stick with all sprays, all rotors, or all rotator heads in a zone. Precipitation rates can vary widely between different types of heads and it is easier to balance with all the same type in a zone. You also want to ensure head to head coverage and an even pattern across the lawn (usually either squares or triangles). I would suggest looking at the articles at: https://www.irrigationtutorials.com/

In particular look at the sections about zone layout: https://www.irrigationtutorials.com/sprinkler-coverage-nozzle-selection-sprinkler-spacings/


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## racng69 (Mar 21, 2020)

Thanks. which rotors would you guys recommend to be the best for 360 coverage. i have the below ones readily available in my market.

- K Rain K2 pro
- Rain bird 5000
- Toro T5.
- Hunter PGP


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## Vtx531 (Jul 1, 2019)

I like the nozzle selection for hunter pgp which is why I bought them for my house. I have had problem with dirt/sand getting in and then the head not rotating anymore but I think I solved this by digging out an inch or two radius around each head.


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## jht3 (Jul 27, 2018)

I am partial to Rainbird 5000. Simple to adjust, including the fixed left stop. Each new head comes with a tree of nozzles. Balance the nozzles based on sweep.

No matter which you go with, be sure to get the special screwdriver tool to make adjustments easier.

Also look into rotators, either Rainbird or Hunter. For under 25' spacing they are superior to sprays due to the lower precipitation rate.


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