You are not logged in.

Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.


Active Member


Monday, April 5th 2004, 4:19pm

Supply Line and GPM Question

My static pressure at the closest hose bib to my meter (in house) is 50 psi. Using the toro psi/gpm manifold set, i only get 3.4 - 4 gpm at 35 psi witch i know is low. My home supply after the meter is 3/4" copper, and the hose bib outside i know is 1/2". Is there a formula or table to tell me what my gpm would be off of 3/4" or is there a big difference?!? Can I turn up my water regulator (max setting of 80 psi) to get a better working pressure or gpm?!?

Also, is it better to run 1" poly after the valves, or should i keep it 3/4"?!?

Please Help.. Thanks.


Advanced Member

Posts: 229

Location: USA


Wednesday, April 7th 2004, 5:59am

go to:

Locate to download the "Hunter Residential Design Handbook"

It lists a table on estimated gpm for meter and pipe sizes. This is a great resource for all you do it yourselfers

As for the poly. Go with the 1"/ Less friction loss and ideal size to work with unless you are doing some very short runs and have low gpm

Rate this thread