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.

Maximus20895

Unregistered

1

Saturday, September 26th 2015, 6:43pm

Only 5 GPM?

Hello,

I am wanting to install a sprinkler system. The problem I am having is that I am only getting 5 GPM from the hose bib.

My Meter is 5/8" from the city and 3/4" copper line to the house. All the numbers I read, people were getting upwards of 10 GPM. Am I just going to have to need 20 zones or what? I am pretty concerned about the low flow rate.

Thanks so much!

Wet_Boots

Supreme Member

Posts: 5,147

Location: Metro NYC

2

Saturday, September 26th 2015, 8:07pm

You aren't necessarily limited to the flow you get from a hose bib. Use your 5 gpm as a baseline, just to work out whether a system is possible, then plan on a re-measurement after you make the supply connection and bring the plumbing to the point where you'll install the backflow preventer.

maximus20895

Unregistered

3

Tuesday, September 29th 2015, 2:12pm

What do you mean if a system is possible?

I've looked at some charts and it says that a 3/4" copper pipe can flow around 11GPM. I am guessing that is the max that it can flow.

Also, I've been looking around at other houses being build in my neighborhood. It goes to the 5/8" x 3/4" meter > 3/4 Copper pipe (about 2 or 3 feet) to 3/4" PEX and the splits off to 1/2" PEX throughout the house. I don't know if any of that matters, I just know that there is quite of bit of restriction from the hose bib that I got my reading all the way to the source.

Thanks for your help I really appreciate it. I'm sure I will have other questions soon!

Wet_Boots

Supreme Member

Posts: 5,147

Location: Metro NYC

4

Tuesday, September 29th 2015, 6:48pm

Answer the question - will you install a system if the available flow is only 5 gpm? Should the answer be yes, then just make the connection and perform a 'bucket test' on it


maximus20895

Unregistered

5

Wednesday, September 30th 2015, 4:39pm

Where did you want me to do the bucket test on?

I already did the bucket test on the hosebib and got ~5 GPM.

I looked at some charts and it states that a 3/4" Copper pipe can flow roughly 11 GPM. So I am assuming that I would get around 8 GPMs when I tie into that.

Thoughts?

Once again, thanks for the help, not just on this thread, but many others that you have replied to. I have been reading constantly about sprinkler systems for around a week now and you have helped me quite a bit by answer other peoples' questions. :)

Wet_Boots

Supreme Member

Posts: 5,147

Location: Metro NYC

6

Thursday, October 1st 2015, 6:42am

You did not do a test with a second shutoff valve and a pressure gauge, or you would have reported the 'dynamic' pressure that accompanied the 5 gpm you measured.

All you are measuring is what the hose bib can supply. Can the meter supply more? You can answer that question better than anyone else by doing your supply plumbing, followed by a proper flow-plus-pressure bucket test.

jsbeckton

Active Member

Posts: 27

Location: Pittsburgh

7

Sunday, October 11th 2015, 7:20pm

Just as a reference, I have a similar setup and was getting 6.5gpm from a hose bib. Tapped into the main 3/4" copper line and had 23gpm there so it can be a huge difference.

maximus20895

Active Member

Posts: 36

Location: Knoxville, TN

8

Monday, October 12th 2015, 8:50pm

Wow! What size is your water meter?

Wet_Boots

Supreme Member

Posts: 5,147

Location: Metro NYC

9

Tuesday, October 13th 2015, 10:49am

That high a flow on a 3/4 line requires very high street pressure, but the meter can be any of the modern 5/8-3/4 types that are rated for 25 gpm or more.

maximus20895

Active Member

Posts: 36

Location: Knoxville, TN

10

Tuesday, October 13th 2015, 8:37pm

I know 15 GPM is the max my meter will allow. Badger model 25, 5/8" X 3/4.

Rate this thread