# Add head or switch sprayer to rotor?



## Buddy (Apr 23, 2018)

I have an existing irrigation system and I'm having trouble getting enough water to my property line. Attached is a diagram with the lined area where I am experiencing dry areas.

Should I switch one or two of my middle spray heads to rotor? Currently they are all Rainbird 15H along the driveway, except for the corner one near the street, which is 15Q. I could switch this corner spray to a rotor, or tap off this line and add another head near the property line in the adjacent corner. My other thought was try and come off the middle heads along the driveway and go to property line that way.

Any thoughts or feedback ?


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## uts (Jul 8, 2019)

What is the length and width of the area?

From what I have read, an ideal system is usually designed like a square or a triangle - position of heads meaning.


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## g-man (Jun 15, 2017)

Most system will need head on the opposite side (property line). An exception is MP strips, but they only spray out to 5ft.


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## Buddy (Apr 23, 2018)

uts said:


> What is the length and width of the area?
> 
> From what I have read, an ideal system is usually designed like a square or a triangle - position of heads meaning.


From the driveway side to the property line, it's about 15'.

Debating if it's worth switching out some sprayer nozzles to a rotor head and get some more water down in the dry areas. Or if it's worth placing a head in the adjacent corner near the street to get the coverage along the property line.


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## GrassOnTheHills (Jul 3, 2020)

As stated by @g-man you should have heads all along the opposite side shooting back to the existing heads. The dry area you're experiencing is due to lack of head to head coverage which really is a requirement of any design.


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## Buddy (Apr 23, 2018)

GrassOnTheHills said:


> As stated by @g-man you should have heads all along the opposite side shooting back to the existing heads. The dry area you're experiencing is due to lack of head to head coverage which really is a requirement of any design.


Afraid that was going to be the only solution to this. With that said, will I be expecting any issues with pressure loss if I add another 3 heads onto that side of the property line? I'm guessing not dramatic, as I have 6 heads, and add say another 3 for a total of 9. I believe my front of the house zone has either 8-9 as well.

Guess the biggest challenge will figure where the main line is and tap off of that. Unless I can come off that head that is near the street/driveway and go across to the property line to add my heads?


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## GrassOnTheHills (Jul 3, 2020)

If you don't mind doing some math, the best thing to do would be to use irrigationtutorials.com to understand the available pressure and the pressure loss of your system, as well as the available flow. Knowing those numbers would tell you if adding heads will present a problem in this instance, but also will let you make decisions like this more easily in the future. In this case, I think only your "safe flow" will matter because if you don't experience pressure issues on that zone now, you won't by adding heads (because a single drop of water will only take one path to a single head), but you will experience a increased requirement for flow (which you may not be able to support).

THAT SAID, if you have another zone with the *same type of heads* with the same *flow requirements* as the ones you want to add to this zone (flow requirements can differ even with the same head depending on the arc used), you should be able to have an equal number of heads on this line assuming the lateral distances aren't wildly different (you'll experience more pressure loss on a long run of lateral than a short).

Lastly, regarding where you'd tap off. If you want to add heads to an existing zone, you'll want to continue the lateral from the last head on that zone. Tapping off the mainline would mean adding another zone (you'd need another valve, otherwise that zone would always be on), which doesn't sound like what you'd want to do. Good news is that will be easier than finding your mainline. Just go to the last head on the zone (assuming you know which one that is...) and run your new lateral from there.


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## Buddy (Apr 23, 2018)

GrassOnTheHills said:


> If you don't mind doing some math, the best thing to do would be to use irrigationtutorials.com to understand the available pressure and the pressure loss of your system, as well as the available flow. Knowing those numbers would tell you if adding heads will present a problem in this instance, but also will let you make decisions like this more easily in the future. In this case, I think only your "safe flow" will matter because if you don't experience pressure issues on that zone now, you won't by adding heads (because a single drop of water will only take one path to a single head), but you will experience a increased requirement for flow (which you may not be able to support).
> 
> THAT SAID, if you have another zone with the *same type of heads* with the same *flow requirements* as the ones you want to add to this zone (flow requirements can differ even with the same head depending on the arc used), you should be able to have an equal number of heads on this line assuming the lateral distances aren't wildly different (you'll experience more pressure loss on a long run of lateral than a short).
> 
> Lastly, regarding where you'd tap off. If you want to add heads to an existing zone, you'll want to continue the lateral from the last head on that zone. Tapping off the mainline would mean adding another zone (you'd need another valve, otherwise that zone would always be on), which doesn't sound like what you'd want to do. Good news is that will be easier than finding your mainline. Just go to the last head on the zone (assuming you know which one that is...) and run your new lateral from there.


Appreciate the insight, and I will review that link you provided. I believe the last head would be the one near the driveway and street.


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## Buddy (Apr 23, 2018)

So I dug around the last sprinkler head that I want to come off from, just to get an initial look. I might have to dig back to the previous head once I really get going on this to get a better idea. But it looked like it was maybe 1/4 pipe going to the head with a Rainbird Spiral Barb elbow, which has 1/4" pipe to it. I don't think there is a swing pipe here, as the line just runs into the elbow, there are no other fittings. So I guess my question is how do I run off this head if there is already 1/4" barb fitting elbow going into the head, and most other corner fittings, elbows go to 1/2"?

https://www.siteone.com/en/1414-131-poly-insert-90-degree-side-outlet-combination-elbow-1-in-x-1/p/31001


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## g-man (Jun 15, 2017)

Do you have a picture ?

If you have the gpm, then a T at the top and a new line on the right side.


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## Buddy (Apr 23, 2018)

g-man said:


> Do you have a picture ?
> 
> If you have the gpm, then a T at the top and a new line on the right side.


Here are a few pictures. I did a GPM test with one of my outside spigots, and it was about 6 GPM. So you'll see from the picture where I put some black mark there is the last head in the zone for the corner. The property line is around where the fence ends for reference. I'm thinking of running more pipe from this last head to add 2-3 more heads on the property line. From the picture the last head has 1/4" pipe running to it. I probably need to continue this size piping for the new heads? Or do I step up to 1/2"? If I did that I would need to find a fitting to go from 1/4 to 1/2".


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## g-man (Jun 15, 2017)

That's called funny pipe. It is made of rubber to use in the last section to the head to allow easy adjustment.

If you have more gpm, then I would dig close to the garage door. Find the pipe that feed all those heads and add a T there to go across to the property line. This will reduce your friction losses.


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## Buddy (Apr 23, 2018)

g-man said:


> That's called funny pipe. It is made of rubber to use in the last section to the head to allow easy adjustment.
> 
> If you have more gpm, then I would dig close to the garage door. Find the pipe that feed all those heads and add a T there to go across the property line. This will reduce your friction losses.


Would I be better finding the pipe that feeds these heads half way down the driveway? What benefit from starting near the garage ? The section that needs more water is in the lower portion closer to the street. I have 4 heads from the garage to the street. So counting from the garage down, if I started at say head 2 or 3 and dug towards the property line I would probably catch the feed line. Then from here I would just run some more feed line to some smaller funny pipe for head placement?

Appreciate all of your assitance.


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## jht3 (Jul 27, 2018)

as others said, that black/blue hose is flexible "funny pipe" or swing pipe. usually you have 12" or so of that from the head to the PVC lateral pipe, where you'll find another threaded/barb fitting.

if you are serious about adding heads, and have the GPM headroom, if were you i would do a bit more excavation until i found the PVC. i'd do this at each head to get an idea how the PVC is run. then cut in new T fittings and trench to add 3 more heads for a triangle layout.

15' is a bit short for a rotor, even turned down. unless you don't mind overspraying into the neighboring yard. what is the head to head distance? also 15'? or something less or more?

the easiest thing would be replace your existing (toro?) heads for rotators, like the rainbird rvan or hunter mp series. i'm using rvans, so you could put in 1804 heads with red/17-24' nozzles and adjust the throw. depending on your actual measurements you may be able to use the yellow nozzles. won't be ideal without a square or triangle setup but should be better than what you have now. if this isn't an improvement, you can always cut in additional heads in fall or spring.


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