SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

Your well within the capacity of the zone if there are no other factors affecting things. Are you covering just lawn or doing both lawn and beds. If both it would be best to split lawn and beds into two zones.

i would definately do 2 zones,mps dont work well unless there is very good pressure,they stop rotating after a year or so especially if they are turned down*,and the stream gets messed up on the sides. look into the rain bird rotary nozzles,they are awsome,they use a bit more water but with 2 zones it would work great,and they spin nice and fast and they dont stop the next year,you cant adjust angle thats the only thing,they come preset,1/3,1/4,2/3 etc... all angles, you can adjust stream down to nothing if you want though which is great,mps can only be adjusted down like 25%. if i had a choice i would use rain bird 3500's,they are tiny rotors with tiny nozzles and they work excellent. its always better to just have 2 zones unless you have insane pressure. its never fun to turn on a zone after install and see that tiny little weak stream,plus if somthing goes wrong you can still run the other one until you can fix the problem. just my opinion. A valve is $15 or so dollars,and they will work twice as good as they would all together if you went with 2 zones. check out the 3500s though, they are actually pretty nice heads

I have a similar question regarding the number of MP Rotator heads per circuit. Given the supply line pressue and GPM requirement to calculate a circuit what in addition to GPM per head is required? Is there any rule-of-thumb on the recommended or maximum number of heads per circuit? I have been told by one person that 8 is recommended maximum per circuit. Is there any truth to this number?



With the low GPM of MP Rotator's I could have 20 heads and not exceed a total GPM of 10 per circuit. Is there a calcuation to determine the line pressure and GPM drop per head to determine an optimum number of heads per circuit? Is there a difference in the number of MP Rotator heads per circuit dependent on whether they are MP1000, MP2000, or MP3000?



If I follow servicetechMA's reasoning 1 head is better then two heads but is not practical. While I understand the reasoning of servicetechMA regarding less heads per circuit is better too many circuits is not practical on large lawns and border areas which require a large number of heads. My watering schedule would be too long. So as asked above what is a recommended average maximum number of heads per circuit given the known supply line pressure and GPM? What is the definition of "very good pressure"? MP Rotators are listed with 40 PSI as the baseline for their GPM down to 25 PSI. They provide 40 PSI check valves reaffirming this is the optimal operating pressure. So is 40 PSI "very good pressure"?

Personally I do not like mp rotators. We have installed thousands of them, My boss likes them for some reason. And when you first put them in,they work pretty good,they do the job,they look pretty good. I just went to a job today actually,5 zones of mps. They had a booster pump for town supply and everything,although they dont have the greatest pressure regardless. I think it was about 7 mp's per zone. Out of 35 or so mp's,3 of them wouldnt open,they get stuck closed and shoot a bunch of streams straight up in the air,3 didnt turn at all,and 3 of them pissed out the left side and didnt spin. 1 year old system too.I cant speak on the competency of the installers,it was zoned well though. Take a look at hunter.com. They have videos of mp rotators working,and they are working awsome.If they worked like that all the time they would be great. But the water pressure behind those heads in the videos is out of this world,and out of 1000+ customers.very few have pressure remotely like that,most of them are town properties with big mains,artesian wells,or big goulds pumps.

If you have a yard that would be 12 zones with 8 heads a zone,well having 24 zones with half the heads is stupid like you said. But if you have a yard that would be maybe 7 zones,with 8 heads a zone,and you could do 9 zones with a couple less heads per zone,thats the way to go. If you dont have awsome pressure,you will be disapointed if you do 8 heads a zone.Im not kidding,they stop turning,they stop rotating if you turn them down,somtimes they do somtimes they dont. They have heavy streams on either side after a couple years. If i were you i would use some rainbird 3500's.We were just given a few boxes for free to try them out. They are little rotors and I personally love them,They are friggen great. The stream is nice and low so they are good for smaller areas.You can also put a bigger nozzle in it and they shoot far. Also check out a few rain bird rotary nozzles,those work great,they always spin,they throw more water than mps,but it just looks like they are doing a better job. Its all a matter of opinion really,some people might think im friggen nuts for hating on the mp's.Just my opinion though man lol, Im 100% Pro Hunter too,heads,clocks,i like their valves. If you had a pump with 60 psi they'd work great for you. I just wouldnt push the limit of heads on a zone. With 2 zones you can water based on different needs sun vs shade several other factors too.You could also just for shits, try it temporarily. Install it above ground real quick and see what 6 look like,see what 8 looks like. I will say it again im not preaching to you,if you want to put 8+ mps on a zone by all means do it.
One of the "SMARTEST" irrigation guys in the country,seriously too he teaches all the seminars,classes,courses,cic cert,everything. He hires us to do the install part while he does the valves,clock,all that stuff. He got out of it to teach irrigation,and manage properties,but hes getting back into it. He swears by mp rotators,and thats what we put in for him,on almost every job. The jobs take 2x longer because there are so many friggen heads all over the place lol. Good luck with whatever you do though

Factoring in your gpm is only half the battle.

While service tech points out some good points.

In my opinion I love them.
The fact is the mp rotator ( along with the toro precision nozzle) uniformity ( How even it applies water) is unmatched to anything else. The fact that you only need 30% overlap and still have a uniformly green lawn .

I just finished installing 25 of these in my yard and in my sidewalk strip. I love the GPM requirement as I have a very low flow rate and a static PSI of 51. They also have the habit of lulling me into a trance as I stare at them rotating. Time will tell how long they last. I am running them on city water but I do occasionally get some small sediment coming through.

I designed my coverage for the MP3000 with a 27ft radius and the MP2000 with an 18ft radius and the head-to-head coverage is dead on. The distance screw on these seems like it does nothing though.