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

Depends on the layout. If I was looking for coverages only between 15 and 27 feet, I'd use the old Toro 300 Stream Rotor heads, which, by the way, have no distance adjustment whatsoever. But they are reliable.

Ok, suppose you don't have pressure regulated valves. Why would it be wasteful to install a pressure reducing valve on the mainline? Seems to me that it would be more cost effective than replacing the valves. As for the well over 100 PSI, I find that quite frequently irrigation installers will use a pressure regulating valve on the mainline over regulated valves almost every time. Which one is more likely to fail first? If a plastic valve gives way, or the pressure regulator is not set right, bam, there goes all of your heads and pipe about 200 feet into the air. A preset pressure regulator right off of the mainline near your point of connection is far more reliable. Most of them come preset anywhere from 50-70 PSI. Im sorry but I don't agree with you on that one, unless you can show me how it is more effective another way.

Adding a pressure regulating valve would be wasteful because the zone valves in this particular system already have flow controls that haven't been adjusted yet. With a static pressure of less than 80 psi, with a RPZ backflow besides, there is no high pressure the system needs protection against. Your standard brass pressure regulating valve has a very high pressure loss, in comparison to a pressure regulating solenoid valve. And even those are intended for a pressure drop of at least 10 to 15 psi. Maybe this system can afford the pressure drop. Maybe not. But to ignore the flow controls already there on the zone valves would be wasteful.

I gotcha. I guess I didn't realize the valves in question had flow control. I was assuming that he was replacing all of the valves with flow control valves. I understand now, thanks for the clarification.