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chules

Active Member

Posts: 8

Location: USA

1

Wednesday, May 2nd 2007, 5:41pm

Design Pressure & GPM

I purchased a Toro PSI/Flow meter and made sure that all water usage was turned off. I have a 3/4 main line from the street and a 5/8 meter. I measured from a 1/2 hose bin a few feet off a T at the meter. The following are my measurements from the Toro gauge

35 PSI Static
With the gauge fully open ( water running and 0 psi ) 8GPM
Measured 5.5 GPM at 20PSI

From what I have read this is very low. Any suggestions for increasing these numbers? Thank you

Wet_Boots

Supreme Member

Posts: 4,022

Location: Metro NYC

2

Thursday, May 3rd 2007, 2:28am

35 psi static pressure is not good. Check to see if a pressure reducer is in the plumbing. Where are you located? Is your water meter in a basement?

A pressure boosting pump would be a common solution to your low pressure. But - (and this is important) - almost every pressure boosting pump and/or system will probably be strong enough to actually create 'negative pressure' in your supply line, making it possible to draw in contamination.


chules

Active Member

Posts: 8

Location: USA

3

Thursday, May 3rd 2007, 2:50am

I am located in Livingston NJ. The water meter is located in the crawl space with closet access. I do not see a pressure reducer anywhere in my home. The house is nearly 60 years old with and old water meter & gate valve. Also, we have completely removed our old landscaping so if a new line or meter needs to be installed I guess the time is now. If I were to install a pressure boosting pump would the installation of a reduced pressure backflow preventer eliminate the drawing in of contamination. Very important since I was planning to install a Fertigator system.

Tom

Supreme Member

4

Thursday, May 3rd 2007, 3:22am

yes with a fertigator system you must install a reduced pressure unit

Wet_Boots

Supreme Member

Posts: 4,022

Location: Metro NYC

5

Thursday, May 3rd 2007, 5:44am

How long would be the new supply line from street to house? It's good to be planning this ahead. A reduced pressure backflow preventer would not prevent the potential of drawing in contamination. Protection requires a supply line that can deliver more water than a booster pump can push. How large is the property?

chules

Active Member

Posts: 8

Location: USA

6

Thursday, May 3rd 2007, 7:00am

I just called the town water department. Pressure in our town ranges anywhere from 35-90psi. I do live on a hill and that may be the cause of the reduced pressure. A new supply line from the street to my home is aproximately 40 feet in length. The water department mentioned that even doing this may not increase the pressure and only increase the volume. They are sending someone to my home to measure the pressure again. I may be that I simply can not install an irrigation system at my home

Wet_Boots

Supreme Member

Posts: 4,022

Location: Metro NYC

7

Thursday, May 3rd 2007, 8:56am

Hills don't help. If your property isn't too (how large is it?) large, you might be able to safely boost the limited supply you currently have, if you can find the appropriate pump. Offhand, I would discard the idea of introducing fertilizer into the water. You want to avoid using an RPZ backflow preventer, if at all possible.

chules

Active Member

Posts: 8

Location: USA

8

Thursday, May 3rd 2007, 11:59am

The water department came by and verified my pressure reading 35 psi static. They are looking into the low pressure as they have on record my location as having 70PSI. In any case, my lot is not large (I do not have my plan on hand) and is less than 3/4 of an acre including my house, deck, driveway and stonework. Not much on the lawn and beds. I came across the Davey HS series pressure pumps and they do mention irrigation and boosting town (metered) psi. I am concerened about water contamination and have been looking into the back-siphonage issue that can surfacwith the use of a pressure booster. I have been compiling a list of parts for the system and when it came to backflow immediately went after the safest solution with the RPZ backflow preventer even with the increased pressure loss - of course this was before I took the reading. I remember reading that RPZ address both backflow & backpressure. For backsiphonage problems an air passage from the atmospheric vent is opened. If the RPZ then protects you from "irrigation" contaminents than what is the increased risk for household water. It's still the same water I currently use just with a greater psi. Is it correct to assume that a pressure booster, backflow & back-siphonage combinations through an RPZ a safe solution?

Thank you for all the assistance

Wet_Boots

Supreme Member

Posts: 4,022

Location: Metro NYC

9

Thursday, May 3rd 2007, 12:59pm

Your town might demand something between their supply and your boosted pressure, apart from any backflow in the system itself. The reasoning is that your boosted pressure is capable of pushing back into the town water. Town Water ~ Check valve(s) ~ Booster ~ Sprinkler Backflow ~ Sprinkler System

All your packaged booster setups are capable of pumping more water than you measured. That's where the 'negative pressure' can happen.

Tom

Supreme Member

10

Thursday, May 3rd 2007, 2:33pm

install the pump after the rp

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