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

Our house has an existing system that the previous owners did not use (~5yrs). I want to use it but not all heads are functioning properly, are angled in the grounds, etc, and I just want to give the system a refresh with matching heads.

I decided to just go with new rotors vs switching to MPs as I originally thought I would. I ended up with Rainbird 5004s (not PRS)..all part circles as I have no full circle needs.

I am not sure how to determine which nozzles to install.
I tested my water pressure off the spigot coming off the meter for the irrigation system. It is 80 psi which I know is high. I do not know if the system has a pressure reducing valve installed somewhere. Would there be a yard box for this if there was. The only yard boxes I have (that I know of) are for the backflow and the zone valves.
How can I test the pressure at the head themselves? I can remove a head and get to the piping if necessary to do this.

In my front yard, it is basically a rectangle with 30' spacing between all heads. Four heads on each side of the rectangle. This would result in 4 quarter circles and 4 half circles across 2 zones (each zone has two quarter and two half cirlces).

How would I determine the proper nozzle to use?? (im a newbie!)

From what I can tell from the nozzle chart, 65 PSI is the closest to what I have. My best guess is I should be looking at using the 1.0 low angle for the quarter circles and 2.0 low angle for the half. These both show a radius close to the 30' spacing I have.

On that note, how much can each head be dialed down in the throw distance. For instance, at 65PSI, the 2.0 says 33ft radius.. is this number the MAX distance, the middle of the range, or....? How much can I increase or decrease that distance?

Any help is very helpful!
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