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

little side-not/addition to what wet boots said. there are 12 normal nozzles that are read with different precip. rates. those grey nozzles are 'low-angle' nozzles for a different trajectory. there are 7 of those nozzles plus one blank nozzle for plugging.

There are twelve different red PGP nozzles for standard trajectory spray, each with a different flow rate. The 0.9 gpm flow rate is for a #2 or #3 nozzle. Very few installs are done with those smallest PGP nozzles, except for inside corners and/or small areas.

If you have room for heads to spray at least 30 feet, use the PGPs. And do some more reading on them, so you understand them better.

I was more curious from a design standpoint. I see with the PGP you can use a red or grey nozzle, which has a drastic difference in the flow rate & GMP.

Hunter has the red nozzle listed by default on the PGP, which has a very low flow & GPM. The grey nozzle has a much higher GMP & rate, and is even higher than the PGJ for the same pressure & distances.

As I questioned earlier, by using the PGP rotors, wouldn't you save quite a bit of money by using the PGP rotors. With the GPM requirements being so low it seems you would be able to reduce the number of zones.

PGJ heads are designed for 15' to 37' distance

PGP heads are designed for 28' to 50' distance

You are ignoring the many nozzle choices that allow you to choose your own precipitation rates.

I mainly question why the GMP is so much lower in the PGP than the PGJ for the same pressure and radius.

If this is true, couldn't you save a lot of money by not having to use as many zones since the GMP is so much lower in the PGP. The PGP heads cost more, but not compared to the extra piping and zone valves needed to use the PGJ heads.

The PGP sprinkler head has been around since the beginning of Hunter Industries, and has been the foundation of many sprinklers built since then. The PGJ was only recently introduced, because many contractors requested a rotor type head that would cover a smaller area. While flow rates may be similar, depending upon the nozzle used, the PGJ is designed with a smaller radius for small lawn areas, and the PGP is designed with a larger radius for large lawn areas.

I assume I am reading the information correctly, but is there really that big of a difference between the PGP & PGJ spray heads? In comparing the two heads at the same pressure (30 PSI) and radius (30') they compare as follows

PGP
GMP - 0.9
Rate .19

PGJ
GMP - 2.5
Rate - .53


In designing my system I am looking at a 50PSI working pressure at 10GPM. To me it seems like I would be better off using the PGP heads since they have a much lower flow rate, but maybe I am missing someting. Am I also correct in that the PGP would have to run at least twice as long as the PGJ to water the same amount?


Why is there such a big difference between these 2 products, and why would you use one over the other?