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

I volunteered to retrofit an old system that uses Hunter PGP nozzles. I know nothing about sprinklers, but am learning fast. The system is old enough the rubber covers on the PGP's are UV-deteriorated and brittle, many covers are missing or cracked. The nozzles are red.

In one area the throw is fine, but the volume is way too high leading to puddles.
What are my nozzle options for keeping the current throw (30-35') but with less volume?
I've tried the set screw, but it is as far out as it can reasonably go.

Should I replace the red nozzles or just clean them?
Any why do the Red and Blue nozzles in the Hunter charts use different PSI ratings (0's for Red, 5's for Blue)?

Do the nozzles wear out? Need cleaning?

If I have a red nozzle and too much volume in an area, how can I lower the volume for that emitter only?

Mr Boots: I have the flow chart, so I know the flow rate per nozzle.


What I'm trying to understand is how to get the maximum spray distance with the minimum GPM flow. The corner of the area in question gets flooded long before the rest of the lawn is sufficiently watered.

I can't readily change the locations of emitters. I will try to put higher flow nozzles on the other side, to minimize the throw on the problem side.

So I went the sprinkler supply house and they say the red nozzles are not only discontinued, but that blue nozzles won't fit in my old spray heads. Why would Hunter do this? The supply house can't get more reds.

I scrounged up a few red nozzles anyway, and found that the lowest flow ones gave the longest throw... but not nearly enough to reach the center of the lawn. Overall pressure seems good, but I don't have a pressure gauge.

I put in a brand new (blue) Hunter PGP and found it had comparable throw to the old one, but leaked more at the base of the popup (leading to a messy muddy puddle on the sidewalk).