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rockee
07-07-2008, 06:52 PM
I had plumber install backflow preventer outside and when water pressure was measured it was 85. He suggested putting in a pressure reducer inside after where water line splits for sprinkler system. Reduce can be adjusted to 25-75 psi. Was this a mistake? should I have stayed with 85 and pressure drop would come down when got to heads? Since I'm putting in many feet of drip, I assumed that a pressure reducer was a good idea. I shaving this large one in-line better than the smaller ones at the zones?

Wet_Boots
07-07-2008, 07:00 PM
You don't need a pressure reducer. 85 psi won't damage anything, and a PRV can screw up your system performance, since it has a pressure loss above and beyond what it takes away when the pressure reduction happens. For the drip zone, you can install an inline regulator, in combination with the strainer the drip zone usually gets.

Mike Leary
07-07-2008, 07:13 PM
You don't need a pressure reducer. 85 psi won't damage anything, and a PRV can screw up your system performance

Ditto city..We kill for that kind of pressure.

CAPT Stream Rotar
07-07-2008, 07:16 PM
ummmm85 psi..

Mike Leary
07-07-2008, 07:20 PM
ummmm85 psi..

Truck with the big boys.

rockee
07-07-2008, 07:34 PM
You don't need a pressure reducer. 85 psi won't damage anything, and a PRV can screw up your system performance, since it has a pressure loss above and beyond what it takes away when the pressure reduction happens. For the drip zone, you can install an inline regulator, in combination with the strainer the drip zone usually gets.

Oh, well. Did I make a mistake? Should I take it out? It is a somewhat expensive valve.

BrandonV
07-07-2008, 07:36 PM
i'd take it out, when I install a well powered system we shoot for 70 psi, that's where all the magic happens.

rockee
07-07-2008, 07:54 PM
i'd take it out, when I install a well powered system we shoot for 70 psi, that's where all the magic happens.

My main is 1" from the inside to the outside. With that size pipe, I still don't need pressure reducer?

Wondering if plumber took advantage or really thought I needed to reduce pressure.

Mike Leary
07-07-2008, 07:55 PM
i'd take it out, when I install a well powered system we shoot for 70 psi, that's where all the magic happens.

Netafim is good to 60psi, I've proved it . Magic works at 70 to 80 psi.

Waterit
07-07-2008, 08:01 PM
My main is 1" from the inside to the outside. With that size pipe, I still don't need pressure reducer?

Wondering if plumber took advantage or really thought I needed to reduce pressure.

You got gotten.

FIMCO-MEISTER
07-07-2008, 08:06 PM
You want the pressure reducer for the house but not the system. I think 65psi is max pressure for a house inmo.

If he put the reducer in after the irrigation system he did the guy good.

rockee
07-07-2008, 09:10 PM
You want the pressure reducer for the house but not the system. I think 65psi is max pressure for a house inmo.

If he put the reducer in after the irrigation system he did the guy good.


I hate to belabor this point. I have a "T" coming off the large main, and it is reduced to a 1" pipe with a shutoff for the sprinkler. The plumber then added the 1" Watts pressure reducer, a pressure gauge, a drain stub, and a second shutoff (in case first one ever fails, he thought second would be a good idea).

Since the PR is good for 25-75 PSI, can't I just wait until sprinkler system (15 zones) is installed, and then installer can adjust pressure up to 75 PSI if necessary. I'm not sure if there is a way to completely deactivate the PR, or if I need to take it out to get back to 85PSI. So, I may just wait until the system is installed before I remove it. Does this make sense?

FIMCO-MEISTER
07-07-2008, 09:32 PM
I hate to belabor this point. I have a "T" coming off the large main, and it is reduced to a 1" pipe with a shutoff for the sprinkler. The plumber then added the 1" Watts pressure reducer, a pressure gauge, a drain stub, and a second shutoff (in case first one ever fails, he thought second would be a good idea).

Since the PR is good for 25-75 PSI, can't I just wait until sprinkler system (15 zones) is installed, and then installer can adjust pressure up to 75 PSI if necessary. I'm not sure if there is a way to completely deactivate the PR, or if I need to take it out to get back to 85PSI. So, I may just wait until the system is installed before I remove it. Does this make sense?

Make sure the system is tied in BEFORE the pressure reducer. You want the pressure reducer on the house only. It sounds to me like you've got a thinking mans plumber. He had to have had an experience which caused him to want you to have that pressure reducer. Rather than second guess him here I'd get him to explain his reasoning a little more thorough to you. Just my 2cents.

rockee
07-07-2008, 09:46 PM
Make sure the system is tied in BEFORE the pressure reducer. You want the pressure reducer on the house only. It sounds to me like you've got a thinking mans plumber. He had to have had an experience which caused him to want you to have that pressure reducer. Rather than second guess him here I'd get him to explain his reasoning a little more thorough to you. Just my 2cents.

I mentioned to him that I was concerned about the high water pressure possibly causing problems with the Netafin, so he was the one who suggested the PR which he put on just the sprinkler system and NOT on the pipe for the entire house - just the section coming off for the sprinkler system. If anything, I wanted the high water pressure in the house. I have used this plumber in the past and will say that he is very competent and neat and thinks, and have no reason to doubt his honesty. Possibly, I shouldn't say this, but I assumed he would know more about controlling water pressure than the installer. The installer would know how to achievethe required pressure. I think with the Watts valve seems like a heavy-duty regulator rather than those plastic zone regulators.

DanaMac
07-07-2008, 10:16 PM
You'll be just fine with the prv in place. we have 100-150 psi here and regulate it down to 50-70.

rockee
07-07-2008, 10:44 PM
You'll be just fine with the prv in place. we have 100-150 psi here and regulate it down to 50-70.

Great forum! Friendly and informative members. Thanks!

DanaMac
07-07-2008, 11:12 PM
Great forum! Friendly and informative members. Thanks!

But, But... remember. If the system isn't DESIGNED for the correct pressure and volume, it will not work properly. We can design a system to work with 30 psi, one head per zone. So don't necessarily take my quote to be all great for all systems.

FIMCO-MEISTER
07-07-2008, 11:19 PM
I mentioned to him that I was concerned about the high water pressure possibly causing problems with the Netafin, so he was the one who suggested the PR which he put on just the sprinkler system and NOT on the pipe for the entire house - just the section coming off for the sprinkler system. If anything, I wanted the high water pressure in the house. I have used this plumber in the past and will say that he is very competent and neat and thinks, and have no reason to doubt his honesty. Possibly, I shouldn't say this, but I assumed he would know more about controlling water pressure than the installer. The installer would know how to achievethe required pressure. I think with the Watts valve seems like a heavy-duty regulator rather than those plastic zone regulators.

I'm looking to the pros here for some help. Installing an irrigation system, have received a few quotes, and narrowed it down to one installer,

I think system is fairly complex, with drip, mist, and rotor zones - 15 zones.

First question. Installer is proposing Hunter PC 15 (PC 300i as controller with 9 and 3 zone modules). Is this a decent one or are there better?
Reply With Quote

I believe you posted this in another thread. You won't be able to use the regulator to adjust your netafim because it will screw up your rotor zones. You need the netafim regulators after the valves operating the netafim. Just leave the regulator in and adjust it to 75 and still figure on the regulators for the netafim.

DanaMac
07-07-2008, 11:21 PM
I believe you posted this in another thread. You won't be able to use the regulator to adjust your netafim because it will screw up your rotor zones. You need the netafim regulators after the valves operating the netafim. Just leave the regulator in and adjust it to 75 and still figure on the regulators for the netafim.

Very true. Good points.

Kiril
07-08-2008, 12:11 AM
My two cents, I wouldn't want 85 PSI in my house, but wouldn't care one bit if I had it for irrigation.

Wet_Boots
07-08-2008, 01:58 AM
If you leave the PRV in, you need to run a flow test before you design the system. PRV pressure-loss charts take it as a given that you are reducing the pressure at least 50 psi. You aren't doing that, starting with 85 psi, so your mileage will vary.

AI Inc
07-08-2008, 05:39 AM
Loosen the lock nut , crank the set screw all the way down and leave it in. Design your system on that and reduce it at the drip zones. done.

FIMCO-MEISTER
07-08-2008, 06:55 AM
I mentioned to him that I was concerned about the high water pressure possibly causing problems with the Netafin, so he was the one who suggested the PR which he put on just the sprinkler system and NOT on the pipe for the entire house - just the section coming off for the sprinkler system. If anything, I wanted the high water pressure in the house. I have used this plumber in the past and will say that he is very competent and neat and thinks, and have no reason to doubt his honesty. Possibly, I shouldn't say this, but I assumed he would know more about controlling water pressure than the installer. The installer would know how to achievethe required pressure. I think with the Watts valve seems like a heavy-duty regulator rather than those plastic zone regulators.

My 2 cents again. The max pressure I'd want in a house is 65. high pressure wears out the faucets causes people to over tighten water handles. Uses more water than necessary. Increases the chances of small leaks in poorly done joints. Also wears out water tanks faster so I'm told. I'd see if you could switch the regulator over to the house line and make sure the irrigation guy uses flow control valves and regulators on the netafim. You might be over thinking this whole thing which has a way of leading to one of our favorite words. KLUDGE