Existing system deficient

purchased home with irrigation system 4 zones. Rainbird system with three 5000 head zones four rotor heads each that work well, but fourth zone has 13 1800 spray heads and worked well with very high pressure. 150 plus. I had a regulator installed to hold pressure at 80 pounds at sprinkler system and then regulated further down to 60 for the house. Now the heads struggle to fully rise above grass. I suspect the regulator reduces water volume in addition to pressure and this is the problem. I would appreciate suggestions as to the best way to fix this situation. I just tried to use R-van rotors thinking it would use less volume but that did not work. Help please?

13 spray heads is too much for a single spray head zone, unless you have a 1" or larger main feeding them. Depending on the nozzles, you could be pushing anywhere from .62 to 2.6 gallons per minute per sprinkler. The R-Vans, depending on the radius, can still require 2.88gpm per sprinkler. chances are you have 1/2" main, or 3/4", and you could be severely overflowing your line.

You could run some calculations and see if the Hunter MP Rotator nozzles will give you enough headroom. The GPM on them is about half of the Rainbird rotary nozzles. They are about $6-7 a piece, so it wouldn’t be the cheapest fix, but the only other option is to repipe the zones and split them into 2 zones.

Thank you, I believe you are right and that means it was designed wrong to start with. The existing spray heads are marginal and will cover but have trouble coming completely up without help. Looks like I need a local contractor and I do not have the original path of all piping. once again thank you for your help.

There is a good chance the Hunter MP’s might work for you. I’ve never actually counted, but ive probably got at least 12 or more on my zones with the MP Rotators. They like lower pressure (around 40psi is PERFECT). Plus the water spray is much more uniform across the arc.

At under $100, you could replace and try. Having a contractor come repipe, you are probably looking at over $1000.

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tmcgahey, I purchased the Hunter heads on the gamble that you were right and the results were spectacular, I now have 14 heads with perfect coverage. They are also so adjustable I was able to set them to cover every inch of the space. Please excuse the gushing but I have been fighting this problem for over four years now both alone and with professional help without success and now it is solved. Thanks again for your help.


Glad to hear.

I LOVE the Hunter MP nozzles. Their adjustability, while still maintaining an even precipitation rate is second to none. Keep in mind, the PR on these nozzles is MUCH less than a standard spray nozzles, so don’t be scared when the zone needs to run 30-60 minutes in order to put down the needed water!

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