# MP Rotator Head-to-Head Distance Issue



## GHTech (Mar 15, 2021)

Hi,

I have 2 zones to cover my 2,000 sq. ft. Bermuda lawn. It is a 56' x 31' rectangle. I have 3 MP3500 along each side per zone, 28' apart, with PRS40 pressure regulated bodies. 2 of the MP3500 are doing 90 degrees, and 1 is doing 180 degrees per zone. According to the chart, that should total up to 5.42 GPM. I just tested the water flow just after the anti-siphon valve, and i am getting 10 GPM. My pressure before the valve is 55 PSI. The MP3500 is supposed to be able to do 31' to 35'. I am having a hard time getting it to hit the next sprinkler head that is at 28'. Any thoughts?

Thanks,

GHTech


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## Delmarva Keith (May 12, 2018)

The first thing I would check is dynamic pressure (pressure while it's running). You have 10 GPM available but we don't know at what pressure at your flow rate. Pressure gauge: https://sprinklersupplystore.com/products/hunter-spray-head-pressure-gauge?variant=43673312777&gclid=CjwKCAjwos-HBhB3EiwAe4xM98tomFPwngFMOjJqgDzhlydxEjbEqWuAF8NMihhbtL6qiOzYKEwnnxoCPYAQAvD_BwE

Another thing to try as more of a quick check is to cap one of the popups and see if the other two change in performance. If so, not enough water.


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## GHTech (Mar 15, 2021)

Delmarva Keith said:


> The first thing I would check is dynamic pressure (pressure while it's running). You have 10 GPM available but we don't know at what pressure at your flow rate. Pressure gauge: https://sprinklersupplystore.com/products/hunter-spray-head-pressure-gauge?variant=43673312777&gclid=CjwKCAjwos-HBhB3EiwAe4xM98tomFPwngFMOjJqgDzhlydxEjbEqWuAF8NMihhbtL6qiOzYKEwnnxoCPYAQAvD_BwE
> 
> Another thing to try as more of a quick check is to cap one of the popups and see if the other two change in performance. If so, not enough water.


Hi Delmarva Keith,

Thank you for the suggestions. Let me try capping off one, and test. I will also get the gauge tomorrow from Amazon. WIll update the thread.

Regards,

GHTech


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## g-man (Jun 15, 2017)

Most likely, your supply line ID is too small for the flow and it is causing a lot of pressure losses.


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## GHTech (Mar 15, 2021)

Greetings,

I just capped off one of them, and there was a slight improvement, but not to the specs. I ordered the MP Gauge, and should get it tomorrow. This should give more data points.

Regards,

GHTech


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## GHTech (Mar 15, 2021)

Hi @Delmarva Keith, @g-man and others,

Received the MP Gauge last evening, and tested all 6 MP Rotators. 1 zone, I am getting 22 PSI on all 3 MP3500's. The other zone I am getting 20 PSI on all 3 MP3500. As both of you guessed, the pressure was low. I then checked another zone that has 10 MP1000's and it was getting 40 PSI on 2 of the MP's that I tested. All 3 zones come off the same mainline . each of them have a anti-siphon value. I believe that this last zone, I put the pipes in. I think I used 3/4" PVC for that. I believe that I used the existing piping for the first 2 zones, with some modifications. Could it be that they may have used 1/2" PVC, and if that could cause the issue?

Any suggestions? I rather not retrench the lawn if I don't have to.

Thanks,

GHTech


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## g-man (Jun 15, 2017)

The only thing to check before digging. Some valves have a flow control on top. Make sure it is fully open.


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## GHTech (Mar 15, 2021)

g-man said:


> The only thing to check before digging. Some valves have a flow control on top. Make sure it is fully open.


It is fully open on both zones. Thanks.


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## GHTech (Mar 15, 2021)

Greetings,

I have 55 PSI at the spigot on the irrigation mainline. I have 5 anti-siphon valves, and get 10 GPM just after that. I have 3/4 PVC pipe. I have 2 zones with 3 MP3500 (31' - 35') Rotators each with the PSR40 bodies. At 40 PSI, the 3 Rotators would be at 5.42 GPM. I need to hit 28' - 31'. As I was not getting head-to-head coverage, I checked the pressure at each head. I am getting only 20 PSI at each. If I cap off 1 head, then I get 30 PSI. I see the same issue in both zones. I reused the original pipes that were in the lawn for these MP Rotators. Is it possible that the previous owners have only 1/2" PVC, and that could be causing the issue? I checked another zone that I put in off the same mainline right next to the 2 zones above. This zone has 10 MP1000 Rotators, and I am getting 40 PSI at 2 of the heads that I checked. There is no pressure regulated bodies in this zone. I believe that I put this zone in, and may have used 3/4" PVC.

Thoughts/suggestions before I have to dig up my lawn.

Thanks,

GHTech


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## corneliani (Apr 2, 2019)

How did you calculate 5.42 gpm for 3 heads? They can put out close to 9-gpm if each travel 180-degrees. Nonetheless it does seem like you have some flow restriction as the math does not add up.

Btw, how did you check the pressure at the head? I see they have a gauge assembly tool (P/N# MPGAUGE) which looks like a useful little tool to have as it verifies pressure at the nozzle.

Last thought ... how long are your runs? Pressure loss is minimal in short runs but those long runs will really amplify them.


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## GHTech (Mar 15, 2021)

corneliani said:


> How did you calculate 5.42 gpm for 3 heads? They can put out close to 9-gpm if each travel 180-degrees. Nonetheless it does seem like you have some flow restriction as the math does not add up.
> 
> Btw, how did you check the pressure at the head? I see they have a gauge assembly tool (P/N# MPGAUGE) which looks like a useful little tool to have as it verifies pressure at the nozzle.
> 
> Last thought ... how long are your runs? Pressure loss is minimal in short runs but those long runs will really amplify them.


Hi corneliani,

I have 2 heads doing 90 degrees (at 40 PSI it is 1.28 GPM each) and 1 head at 180 degrees (at 40 PSI it is 2.86 GPM), so a total of 5.42 GPM should be what I am using if I had the 40 PSI. I did get the MPGAGUE to check at each head. My runs are not that long. The furthest would be about 80'.

Regards,

GHTech


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## corneliani (Apr 2, 2019)

GHTech said:


> corneliani said:
> 
> 
> > How did you calculate 5.42 gpm for 3 heads? They can put out close to 9-gpm if each travel 180-degrees. Nonetheless it does seem like you have some flow restriction as the math does not add up.
> ...


That adds up... but that PSI drop makes no sense unless there's blockage or, like you suspect, smaller pipe. Looks like there's no choice but to dig, eh. :bd:


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## burntfire (Dec 10, 2020)

Did you actually verify you're getting 10 GPM? What size is your main?

The heads are more than likely on 1/2" PVC.


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## GHTech (Mar 15, 2021)

Greetings,

A quick update. I dug up the pipes a bit in 2 locations, and it looks like the pipes are 3/4". Then I thought the issue might be in the old Champion anti-siphon valves. I swapped out one for a old brass anti-siphon valve that did not have a actuator. I was originally getting 20 PSI at each head. After the swap, I was getting 30 - 32 PSI at each head. I am thinking that the best course of action might be to replace the PRS40's with PRS30's, and also replace the brass anti-siphon valves with new ones, as replacing parts might end up costing as much. Thoughts please?

Thanks,

GHTech


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## Amoo316 (Jul 8, 2021)

IMO I would just spend the money now and do what you feel you will be happiest with long term.

It's easy to spend somebody else's money, but I'm of the opinion, working with sprinklers is such a labor intensive thing, that I'd rather do it the way I want it the first time then have to go back and change something later.


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## GHTech (Mar 15, 2021)

burntfire said:


> Did you actually verify you're getting 10 GPM? What size is your main?
> 
> The heads are more than likely on 1/2" PVC.


Hi @burntfire

I did the bucket test just after the anti-siphon valve, and got 10 GPM. My mainline is 3/4" PVC. I did check the static pressure just before the anti-siphon valve, and I am getting 60 PSI.

Regards,

GHTech


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## GHTech (Mar 15, 2021)

Hi @corneliani, @burntfire and Everyone,
Updated Info:
I have 2 zones of 3 MP3500 each, changed from PGP's installed 15 years ago. I have 60 PSI static before the brass anti-siphon valve. I have 10 GPM on the out of the valve. I have 3/4" (what I can see) PVC going to 3 MP3500 (2 at 90, and 1 at 180 degrees). I dug up the areas around each MP to confirm pipe size. Pipe is 60' long. Static at 1st MP is 50 PSI, and 30 at the 3rd. While running (using the MP Gauge), I get 30 PSI on each. If I cap off 2 MP's, I get 35 on 1 MP. Max. distance I get even with 1 MP running is about 28' (suppose to be 31' to 35'). My other zone is at 20 PSI running.

Thanks,

GHTech


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## GHTech (Mar 15, 2021)

Hi @Delmarva Keith, @g-man, and Everyone,

Updated Info:
I have 2 zones of 3 MP3500 each, changed from PGP's installed 15 years ago. I have 60 PSI static before the brass anti-siphon valve. I have 10 GPM on the out of the valve. I have 3/4" (what I can see) PVC going to 3 MP3500 (2 at 90, and 1 at 180 degrees). I dug up the areas around each MP to confirm pipe size. Pipe is 60' long. Static at 1st MP is 50 PSI, and 30 at the 3rd. While running (using the MP Gauge), I get 30 PSI on each. If I cap off 2 MP's, I get 35 on 1 MP. Max. distance I get even with 1 MP running is about 28' (suppose to be 31' to 35'). My other zone is at 20 PSI running.

Thanks,

GHTech


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## g-man (Jun 15, 2017)

I think your setup should be working. The only potential problem could be an issue with the PVC pipe.


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## GHTech (Mar 15, 2021)

g-man said:
 

> I think your setup should be working. The only potential problem could be an issue with the PVC pipe.


@g-man 
I was describing my situation to a friend who handles the grounds department where I work, and he suggested that I flush the system from downstream towards the anti-siphon valves, after disconnecting the anti-siphon valve. Will cap off the first 2 "Tees". I will try that today, and see how it goes. Will update.


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## corneliani (Apr 2, 2019)

Make sure & check the rotator screw setting to make sure it's throttled all the way open. Sometimes it's the obvious things &#128556;


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## GHTech (Mar 15, 2021)

corneliani said:


> Make sure & check the rotator screw setting to make sure it's throttled all the way open. Sometimes it's the obvious things 😬


Hi corneliani ,

Thanks. Yes, I opened it up fully. Agreed, don't to dig the whole place up, and then find out it was a small thing that I missed.

Regards,

GHTech


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## burntfire (Dec 10, 2020)

g-man said:


> I think your setup should be working. The only potential problem could be an issue with the PVC pipe.


This. I bet you it's class 200 PVC (which have thin walls but great for maximizing GPM) and got some roots in there blocking it a bit. You'd be surprised how stuff can make its way into pipes.


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## GHTech (Mar 15, 2021)

Quick update:

I have dug up about half of the 60' run that has the 3 MP3500's, and it looks like I have 3/4" PVC throughout. My static pressure before the anti-siphon valves is 60 PSI and 50 PSI after. I replaced all of the swing assemblies by running 3/4" PVC to each head. I am still getting only 25 PSI (dynamic) at each head. But, the volume of water seems to be better.

Should I dig up the rest of the pipe, or ... Any thoughts?

Thanks,,

GHTech


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## corneliani (Apr 2, 2019)

25psi pressure loss seems like a lot in 1 small residential zone. Friction loss per 100ft of Sch40 pipe (if that's what you have) can eat up 5-10+ psi - that may be a chunk of it right there - but that's barely half of your loss. Could it be you have lots of fittings that are further eating into your pressure?? 
If you already dug half the zone open might as well continue, IMO.


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## Delmarva Keith (May 12, 2018)

You mention static pressure just before and after the anti-siphon. Can you measure the dynamic pressure at those points? Maybe somehow you have less available flow than you think? I'm just having trouble wrapping my head around a roughly 5 GPM demand (if I remember right) through 3/4" pipe that isn't making the nozzles sing. Something is constricting or diverting flow somewhere.


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## burntfire (Dec 10, 2020)

How old is the system? I can almost guarantee there's a blockage in the pipes if it's being reduced that drastically. If you're main loss is after the 2nd head I would assume it's between there and the 3rd.

As @Delmarva Keith mentions those MPs should be absolutely singing OR you have a leak in the pipe. Any abnormally wet spots?


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## GHTech (Mar 15, 2021)

Hi @corneliani, @Delmarva Keith and @burntfire ,

I will respond to the individual questions after this post. I just went home to check the PSI (static and dynamic). I have a spigot on the main line to the back garden sprinkler system that I took the numbers from just now. From here it goes through 7 elbows and about 25' of 3/4" schedule 40 PVC to the anti-siphon valves.

Static pressure was 68 PSI. When I tested the PSI just before anti-siphon valve about a week ago, it was 60+ PSI static.

Zone 4: 10 MP1000 rotators: dynamic pressure was 51 PSI at spigot.

Zone 5: 3 MP3500 rotators: dynamic pressure was 42 PSI at spigot.
Zone 5: Dynamic pressure at the 1st MP3500 that is 12' from the anti-siphon valve with 1 elbow is 28 PSI

Zone 7: 3 MP3500 rotators: dynamic pressure was 44 PSI at spigot.

My zone 5 and 7 are for the 2000 sq. ft. lawn.

Thanks,

GHTech


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## GHTech (Mar 15, 2021)

corneliani said:


> 25psi pressure loss seems like a lot in 1 small residential zone. Friction loss per 100ft of Sch40 pipe (if that's what you have) can eat up 5-10+ psi - that may be a chunk of it right there - but that's barely half of your loss. Could it be you have lots of fittings that are further eating into your pressure??
> If you already dug half the zone open might as well continue, IMO.


Hi @corneliani ,

Yes, it does not make any sense. Please see the post with the details. I will dig the rest if I have as I don't want to cover it up now, and find out in a year that the pressure dropped further.

Thanks,

GHTech


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## GHTech (Mar 15, 2021)

Delmarva Keith said:


> You mention static pressure just before and after the anti-siphon. Can you measure the dynamic pressure at those points? Maybe somehow you have less available flow than you think? I'm just having trouble wrapping my head around a roughly 5 GPM demand (if I remember right) through 3/4" pipe that isn't making the nozzles sing. Something is constricting or diverting flow somewhere.


Hi @Delmarva Keith

I checked the flow just after the anti-siphon valves, and I was getting 10 GPM. Please see post above.

Thanks,

GHTech


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## GHTech (Mar 15, 2021)

burntfire said:


> How old is the system? I can almost guarantee there's a blockage in the pipes if it's being reduced that drastically. If you're main loss is after the 2nd head I would assume it's between there and the 3rd.
> 
> As @Delmarva Keith mentions those MPs should be absolutely singing OR you have a leak in the pipe. Any abnormally wet spots?


Hi @burntfire

When we bought the home about 15 years ago, and I added to the existing system about 14 years ago. I put in Hunter PGP's at that time, and i think it was pretty good then. I recently replaced all 6 PGP's (2 zones) with MP3500's as the there was coverage issues. Now, I am seeing the pressure issue in both zones. I replaced the anti-siphon valves on both those zones about 2 weeks ago.

Thanks,

GHTech


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## spaceman_spiff (Feb 5, 2021)

Side question, but what do you use to dig that cleanly? When I dig up a head, it looks like a messy, muddy explosion using a shovel for the larger chunks and a trowel to work around the head and PVC. I absolutely can't stand digging down and around the PVC when I'm looking at risers and whatnot. Just curious if there was an easier way to dig, especially since my clay yard is absolutely saturated with tree roots.

I haven't even tried trenching out PVC. Digging up a single head takes me forever.


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## GHTech (Mar 15, 2021)

spaceman_spiff said:


> Side question, but what do you use to dig that cleanly? When I dig up a head, it looks like a messy, muddy explosion using a shovel for the larger chunks and a trowel to work around the head and PVC. I absolutely can't stand digging down and around the PVC when I'm looking at risers and whatnot. Just curious if there was an easier way to dig, especially since my clay yard is absolutely saturated with tree roots.
> 
> I haven't even tried trenching out PVC. Digging up a single head takes me forever.


Hi @spaceman_spiff

Sorry for the late response. I use a digging shovel to cut the outline, and then pull that section out. But, most of the sections that I dig out ( 5" - 6" deep), never seems to grow back. Seems to kill the grass.

Regards,

GHTech


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## GHTech (Mar 15, 2021)

Quick update.

Before i trench the whole line, I thought that I will bypass all the old piping to see if a block was causing the issue. As you can see, I put together a crude setup to run all 3 MP3500's using 3/4 PVC, and there was no difference in the PSI (28) or the distance that it threw. I tried putting 3 MP3000 with a slight improvement of the PSI (30), but distance was a bit less as expected. The 3 MP3000 requires 3.1 GPM at 30 PSI vs. 4.29 GPM at 25 PSI for the MP3500.

I will put the system back together so that the grass does not die. I will go through the whole irrigation tutorial as if I am designing a new system, and see if there is some modification that will improve things.

If anyone has any thoughts, please let me know.

Regards,

GHTech


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## Delmarva Keith (May 12, 2018)

No matter how you slice it, it has to be that you don't have enough flow. You measure 10 GPM with zero back pressure or friction loss, but around 3.1 GPM at 30 PSI when you run it through however your supply is setup. Something between the township water tower and your sprinkler heads is constricting flow. I can't tell you what that is, but something in the end-to-end has to be affecting it.

Here's one thing that comes to mind which might be worthwhile - whichever bib connection you are using to measure static pressure and at which you measured 10 GPM (after the anti-siphon I think you said) screw on one of those wye connectors with the two valves: https://www.amazon.com/Riemex-Garden-Splitter-Upgraded-Connector/dp/B07TSL73L2/ref=sr_1_8?dchild=1&gclid=EAIaIQobChMI6f2fhMKh8gIVT2xvBB3zzwe7EAMYAiAAEgI9GPD_BwE&hvadid=243510018366&hvdev=c&hvlocphy=9007519&hvnetw=g&hvqmt=e&hvrand=5929556598954729891&hvtargid=kwd-301649263090&hydadcr=26718_9853953&keywords=y+hose+connectors&qid=1628428872&sr=8-8

Screw on your pressure gauge on one outlet or the wye and use the other outlet as your discharge; open both valves on the wye. Open the supply bib you are using and note dynamic pressure. Start to slowly close the discharge side valve on the wye until the pressure gauge reads, say, 45 PSI. This is 45 PSI dynamic. Now time and measure your flow at the discharge. My guess is, based on the symptoms you've described, you'll see something less than 3 GPM. What you're going to have to do is find the point in the system where you can get around 45 PSI dynamic at at least a 5 or 6 GPM flow. When you find that point, you'll know what it is after it that was constricting your flow


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## GHTech (Mar 15, 2021)

Delmarva Keith said:


> No matter how you slice it, it has to be that you don't have enough flow. You measure 10 GPM with zero back pressure or friction loss, but around 3.1 GPM at 30 PSI when you run it through however your supply is setup. Something between the township water tower and your sprinkler heads is constricting flow. I can't tell you what that is, but something in the end-to-end has to be affecting it.


Hi @Delmarva Keith ,

Thank you for responding. I will try your suggestion. Just for clarification. I know that I was able to get the 10 GPM when I checked at the anti-siphon valve. But, I did not check the dynamic pressure at that time. When I had the 3/4" PVC cut, and was flushing it, there was significant water flow. I assume your concern is that even though the water volume is there, the PSI could be close to zero, and therefore not workable. Right? Just checking.

I wonder if my pressure regulator for the house and irrigation (Zurn NR3XL) could be causing the pressure drop.

Regards,

GHTech


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## corneliani (Apr 2, 2019)

@GHTech you, my friend, are relentless!!! I'm going to stay on top of this thread since I'm outright curious what the final outcome will be. You don't seem the type to give up easily


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## GHTech (Mar 15, 2021)

corneliani said:


> @GHTech you, my friend, are relentless!!! I'm going to stay on top of this thread since I'm outright curious what the final outcome will be. You don't seem the type to give up easily


Hi @corneliani ,

 Thanks. I know the theory says that this makes no sense. If the theory matches the real life data, then it makes sense and I will let it go. I guess my regular job gets the better of me. 

Regards,

GHTech


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## g-man (Jun 15, 2017)

What is the pressure after the Zurn NR3XL?

What brand of siphon valve is there? What is the pressure drop across the valve?


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## GHTech (Mar 15, 2021)

g-man said:


> What is the pressure after the Zurn NR3XL?
> 
> What brand of siphon valve is there? What is the pressure drop across the valve?


Hi @g-man

The static pressure just after the NR3XL is 65 PSI. I am getting similar static pressure in the spigot in the back garden just before the anti-siphon valves. I had the Champion and Superior brass anti-siphon valves. I replaced the 2 zones that I am having problems with with the Orbit brass anti-siphon valves. When I checked before (before the replacement)it went from 60 PSI down to 50 PSI static drop just before and after the anti-siphon valves.

Regards,

GHTech


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## g-man (Jun 15, 2017)

It would be nice to draw up your setup on paper and take a cell picture of it. It is confusing trying to get all the info one post at a time.

Is this the valve? How do you then turn on and off the zone? Is there another valve in the system? Master valve?

https://www.dripdepot.com/product/orbit-three-quarter-inch-fpt-brass-anti-siphon-sprinkler-valve

The 10 psi drop across the valve is with the system running or static? The amount of pressure drop is a function of flow.


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## GHTech (Mar 15, 2021)

g-man said:


> It would be nice to draw up your setup on paper and take a cell picture of it. It is confusing trying to get all the info one post at a time.
> 
> Is this the valve? How do you then turn on and off the zone? Is there another valve in the system? Master valve?
> 
> ...


Hi @g-man ,

I have the 3/4" brass anti-siphon valves with the actuator on it. All the zones are connected to a Rachio 3. Understood about having a drawing will really help. Will try that tomorrow.

Thanks

GHTech


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## Delmarva Keith (May 12, 2018)

GHTech said:


> Delmarva Keith said:
> 
> 
> > No matter how you slice it, it has to be that you don't have enough flow. You measure 10 GPM with zero back pressure or friction loss, but around 3.1 GPM at 30 PSI when you run it through however your supply is setup. Something between the township water tower and your sprinkler heads is constricting flow. I can't tell you what that is, but something in the end-to-end has to be affecting it.
> ...


Yes, flow at pressure is what you need, not just pressure. Look at it sort of this way, 10 GPM is always going to deliver 10 gal every minute, but at 5 PSI those 10 gal will make a puddle, and at 50 PSI the same 10 gal will run several heads. Makes a big difference. The test you already did was a 3.1 GPM flow resulting in 30 PSI dynamic. That tells me that your available flow is considerably less than 3.1 GPM at, say, 45 PSI dynamic, which is around a minimum dynamic you want. As @g-man is pointing out, you have to have a constriction or limiting aspect somewhere.

If you run the quick and easy test I outlined, you'll get a rough idea of what you actually have available (at least available out of a hose bib) - a measured volume at a measured dynamic pressure.


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## Delmarva Keith (May 12, 2018)

GHTech said:


> g-man said:
> 
> 
> > What is the pressure after the Zurn NR3XL?
> ...


As another thought, you keep referring to static pressure measurement which is meaningless except to confirm the maximum pressure when there is flow demand that you can theoretically ever have. You need to accept that dynamic pressure is what you need to know - forget static pressure for a bit. If you are able to easily measure static pressure at those points, you can just as easily measure the dynamic pressure at those points. Having those dynamic pressure measurements might provide more clues to what's wrong.

Just to confirm we're using the same meanings - static pressure is pressure in pipe with no flow; dynamic is pressure with flow (heads running). Just want to be clear


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## GHTech (Mar 15, 2021)

Hi @Delmarva Keith ,

I guess I should rig up something like this. 






Regards,

GHTech


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## Delmarva Keith (May 12, 2018)

Yes! That will do. The wye setup might be easier but whatever works.


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## GHTech (Mar 15, 2021)

Hi,

My issue could be due to the pressure regulator valve (feeds the home and irrigation lines) acting up. One should be able to open the bell housing to see if there is debris causing a block, etc. I tried opening the plastic housing after backing off the screw, but it is not opening, and I fear that I will crack it. I know that I replace the regulator (Zurn NR3XL) a few years ago. I have ordered a new one that should arrive tomorrow. Will update after I swap it out.

Regards,

GHTech


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## GHTech (Mar 15, 2021)

Greetings,

Update: I tried to open up the pressure regulator valve (Zurn NR3XL) to check if there was any debris inside. Was not able to take the plastic cover off. Ordered a new one and replaced it. Had to force the top off to take a peak inside the old one.



There was a definite improvement with the new one. I set the static pressure at the valve to 65 PSI. Following is in the irrigation system.

Static pressure at spigot on irrigation line, 20' before the anti-siphon valves. 


Dynamic pressure while running the 3 MP3500 zone.


Pressure at the furthest MP3500.



The MP3500's are performing much better, and are hitting head-to-head.

I do still have an issue as to why I have a drop of 20 PSI (dynamic) between the spigot and the last MP3500. There is only about 90' of 3/4" PVC, one 3/4" Auto Brass Anti-Siphon Valve and 2 other MP3500's in the way.

https://www.homedepot.com/p/3-4-in-Auto-Brass-Anti-Siphon-Valve-57065/100342865

I have not updated the other zone (same config) that still has the PRS40 bodies, and has the 1/2" swing assemblies.

Regards,

GHTech


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