# Need help/advice on current MP Rotator zone



## Stylez78 (Sep 10, 2021)

Hi all, I setup a map with my zone layout where each head is, the actual nozzle being used and the distances from head to head. The company that installed the system used the hunter-prospray bodies not the psi regulated bodies. In the map the black area is a bed with some shrubs by the house, there is no head there but it gets some over spray from the 2 rotator heads.

After having this a year, there a few dead spots of grass around in this zone and just looking at the distances compared to specs, I can clearly see I am not getting head to head coverage and the company who laid this out probably should have adjusted this. Most of the heads in this zone are MP2000 90-210 which at 40 psi should shoot 19ft. Even the ones that are within the 18-19ft distance I can clearly see that the spray does not even reach the other head. Clearly the ones over 18ft (20-23ft) def aren't reaching.

I have 2 other heads on this zone not picture as they are behind a fence but I don't think I even need them and will have them removed but for calculation purposes since they are active now, it gives me 12 MP2000 90-210 heads that should be taking up .86 GPM if they shot 19ft at 40psi and then 1 MP2000 360 that takes 1.48 gpm at 40psi 19ft. That should be 11.8 gpm flow rate. Last time I measure my flow rate from the spigot that come off the line that feeds the sprinkler, so it is after the Backflow preventer but before any the sprinkler valves it was 13gpm. I ordered a hunter psi gauge to measure the psi at each head so I can know all the info before trying to make adjustments.

Few questions I have:

1. If there is 40 psi at a head, what would cause the head to not hit the 19ft distance? (I have used the tool and made sure it was set to make distance).
2. Would it make sense to chance the 360 head to an MP3000 and possibly tune it down to it's minimum radius to help make up some coverage throughout the zone? I also know I have to keep in mind the flow rate 
3. Any other things I can do or consider to improve what this company did with this install?


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## dofdk3 (5 mo ago)

Couple of questions I have right off:

I'm assuming the system is tied into your main? So I'd be curious what size lines are being used underground.

My other question would be why they stretched the system so thin. They used the same head/nozzle in each spot but your distances vary greatly in some spots. Some of the variations in distance are as high as 6ft where I would think some of those gaps would either be equal, or evenly staggered.

Most importantly though, my top question is line size. With that kind of flow and pressure, I'd think you should have 1" PVC everywhere, maybe tapered to 3/4" in long distance runs.

Also, how many zones total?


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## Stylez78 (Sep 10, 2021)

dofdk3 said:


> Couple of questions I have right off:
> 
> I'm assuming the system is tied into your main? So I'd be curious what size lines are being used underground.
> 
> ...


I'll do my best to answer everything. I'm not sure the size of the main underground, but where the main comes into the house that is 3/4" copper. That runs to the garage then it taps off to more 3/4" copper that then hits the backflow, more 3/4" copper to the outside where the put a hose spigot and then ran the pipe to the valve boxes.

The said they used 1" polysomething or other pipe to run under ground for each zone. The used the machine to bury and run the pipe in the ground.

As to why the stretched it thin? Not sure, I trusted they knew what they were doing but best thing I can say was they were lazy and didn't want to put more heads or do another zone. They probably wanted to cut cost and increase their profit. but that is just me guessing.

I could call them back, complain but not sure what they could do or if I want to even pay them to fix what they should have done right first time around. Just wondering what I could do right now to fix certain parts (the longer gaps over 19ft) but what to do or test and try to figure out why heads that should shoot 19ft aren't and maybe how to trouble shoot the potential cause and what I could do to remedy that.


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## dofdk3 (5 mo ago)

@Stylez78 and how many total zones do you have in the map you shared above?


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## Stylez78 (Sep 10, 2021)

@dofdk3 sorry thought I put that. The system has a total of 7 Zones. The map above is just 1 zone. This the first one I am auditing. Zone 2 is seems setup a tad better but I need to measure but wanted to fix zone 1 first since I'm over seeding in a week and want to make sure I have the best coverage I can.


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## dofdk3 (5 mo ago)

@Stylez78 im sorry. I didn't read clearly enough. You had already stated it was 1 zone.

I think that's your issue. I know on paper you're sitting at 13gpm from the spigot and math says you're only at 11.8gpm but I think the distance we're covering and variations in pressure is the issue.

Personally, I think this should have been 2 zones.


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## Stylez78 (Sep 10, 2021)

@dofdk3 is there anything I can do that wouldn't entail ripping up the ground to split up the zone? I have called the company who installed it to inform them this zone is performing poorly butni don't think they going to fix their setup mistakes cost free.

Is there a way to check if it is a flow issue or if it is something else?

The ones that have longer distances like 20-25ft the heads never going to reach cause they rated for 19ft max at 40psi.

Would having to use MP3000 in certain spots dialed down be an option and split the zone so flow isn't an issue?


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## dofdk3 (5 mo ago)

@Stylez78 I would try swapping for a MP3000, sure. Looks like all of their rotary nozzles are calibrated for 40psi. You'd only be out a few bucks and 10 minutes. Worth a shot.


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## g-man (Jun 15, 2017)

Switching to mp3000 can help, but it will increase your GPM. I think you might be at the limit. Do you know the layout of pipes? Maybe there is a way to split the zones.


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## dofdk3 (5 mo ago)

g-man said:


> Switching to mp3000 can help, but it will increase your GPM. I think you might be at the limit. Do you know the layout of pipes? Maybe there is a way to split the zones.


He's spot on. Didn't even think about increasing your gpm.


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## Stylez78 (Sep 10, 2021)

g-man said:


> Switching to mp3000 can help, but it will increase your GPM. I think you might be at the limit. Do you know the layout of pipes? Maybe there is a way to split the zones.


I remember that they ran the pipes across the yard. So looking at the picture I provided it would be from top to bottom, but I am not sure how they connected it all as the valve boxes are on the other side of the house and around back.

I can cap off 2 heads not pictured on the layout I provided that are both MP2000 90-210, that are on the other side of the fence and I don't really need as I am going to eliminate the grass their and put a patio. So that would take off 1.72. The MP3000 360 would be 3.64 but if I tuned it down may use less so it could be inline with what gets used now but I am not sure if that truly solves the issue. Right now the MP2000 heads aren't even getting their rated 19ft so I am most concerned with trying to figure out why that is. Is it Flow or psi? psi I can easily test with the gauge but how can I test what the flow is at the head and if it is enough or too little? I would think this is the biggest issue to tackle because it seems like the first 9 heads in the box kinda fall into the 18-20 range so if they shot their rated distance should be fine. Feel like the smaller rectangle with the 23-25ft distance will be an issue to tackle as the spacing just seems to be too far apart.

Another issue is with how this is setup, is there a way to even get an optimal spray pattern with how they put the heads?


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## dofdk3 (5 mo ago)

@Stylez78

Just fyi. I picked up an mp3000 to test it. Just doing a straight up swap in one of my zones, I wasn't currently pushing enough to get the head to rotate properly.

Take that for what it's worth.


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## Stylez78 (Sep 10, 2021)

dofdk3 said:


> @Stylez78
> 
> Just fyi. I picked up an mp3000 to test it. Just doing a straight up swap in one of my zones, I wasn't currently pushing enough to get the head to rotate properly.
> 
> Take that for what it's worth.


After much arguing I got a guy from the company to come out. He watched the system run and said the flow probably dropped I should call the water company. We argued as I said he designed the system poorly they shoulda made 2 zones.

He then swapped 2 heads, 2nd row bottom and 3rd row bottom on the map with MP3000 heads. Turned system on and those shot further than the MP2000 did while all other heads stayed the same. Now the MP3000 should shoot 30' at 40psi these are shooting 20ish. So it really is weird situation. The heads on the zone map in row 2 3 and 4 that are 20+ feet get the least water and have the worst looking grass atm. The guy dis nothing there and pretty much told me I need to split the zone but gave no indication he wanted to do it and now I can see I will be stuck forking over $ to fix their mistake unless I can figure out a way to fix it myself.

Tomorrow I am going to test psi at all the heads in the zone see what they are at. I don't have a flow meter but I'm gonna try the 5 gallon bucket test as well see what is up.

Maybe the answer is using Rotors in this zone but with the current head layout not even sure how I'd make that work on just 1 zone....sigh what a pita this is


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## g-man (Jun 15, 2017)

Since it is all one zone and 3/4 copper line, you should not exceed 11gpm per zone.

https://web.archive.org/web/20211214003928/https://www.irrigationtutorials.com/gpm-psi-municipal-water-source/

Depending on your layout, it might be possible to split the zones in two via adding two new valves. The current valve is bypassed/keep open and the two others are used to split the zone. But it all depends on the layout.


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## FailedLawn (5 mo ago)

The mp2000-90 @40psi should flow 0.4gpm at 19', not 0.84. Not sure if that was a typo or miscalculation.
Regardless, 11 heads on one zone may be the main issue with the install.

https://www.hunterindustries.com/sites/default/files/CA-Cutsheet-MP-Rotator-US.pdf

Depending on how the lines are ran, it may not be too much work to cut the zone in half and run it separately. This would depend where the valves are located and if there's extra wire already pulled to the box. It could be pretty simple, or a ton of work.

If they gave you a layout of where the lines are or if you have pics/sketch, can you share it here?


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## Stylez78 (Sep 10, 2021)

FailedLawn said:


> The mp2000-90 @40psi should flow 0.4gpm at 19', not 0.84. Not sure if that was a typo or miscalculation.
> Regardless, 11 heads on one zone may be the main issue with the install.
> 
> https://www.hunterindustries.com/sites/default/files/CA-Cutsheet-MP-Rotator-US.pdf
> ...


Based on the hunter specs the Mp2000 90-210 will vary on the flow GPM based if it is set to 90 or 180 or 210. Most my MP2000 are set to 180 and while they are MP they drop .4 inch of water per hour but the flow gpm each head is using is probably closer to .77gpm.

I am going to see if I can get a map of how they ran the pipes since they never provided one. I have tested the furthest heads on the system from the valve box in this zone and it is measuring about 38 psi when all heads in the zone are on. I don't have what my static PSI is right now as the gauge I have to test that is lost, have to go buy a new one but last year I am pretty sure it was measured at around 60 psi after the back flow valve. So it really should run through the sprinkler valve box and through the lines to the head, so seems like a big drop from 60-38. Still 38 doesn't seem terrible (other heads in the zone also showed 38psi).

At this point I totally regret going with this MP setup and the company I chose.


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## FailedLawn (5 mo ago)

You're totally right on the coverage angle affecting GPM. My mistake.

Static pressure doesn't so much matter to you. It's the working pressure that really counts. If you have ~38 to 40 psi at the heads during operation you should be in the ballpark. As pressure decreases, so will your sprinkler coverage.

While some of your spacing isn't exactly ideal, you should be able to make some adjustment and swap out a few 3000's and resolve some overlap from the existing design. However the 3000 will flow even more and you may run into a lower pressure situation.

That's probably where I would start and if it doesn't work, split that area into a second zone.

Is there a zone valve in this area? If yes and there's and extra wire in the box from the controller, it could be split in a few hours time with a shovel and ~$100 in parts.


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