Register free!
Search
 
     

Click for Weather
Reply
 
Thread Tools Display Modes
  #11  
Old 09-26-2013, 08:35 PM
Wet_Boots's Avatar
Wet_Boots Wet_Boots is online now
LawnSite Fanatic
 
Join Date: Mar 2005
Location: metro NYC
Posts: 39,523
The actual maximum flow ratings for backflow preventers matches that of water meters of the same size, and that is way off the charts compared with what flow rates you will actually be working with. You can get away with high flow rates in PVBs and DCVAs much more than you can with RPZs, which will spit water from the relief valve when a downstream valve slams shut.
Reply With Quote
  #12  
Old 09-26-2013, 08:46 PM
jbailey52's Avatar
jbailey52 jbailey52 is offline
LawnSite Bronze Member
 
Join Date: Dec 2004
Location: Horticulture
Posts: 1,052
So can someone explain a little more to me... If you use a 3/4 backflow on a 5/8" meter, what size pipe is feeding the backflow, and which leaves the backflow? All 1" with 3/4" fittings for the backflow?
Posted via Mobile Device
Reply With Quote
  #13  
Old 09-26-2013, 09:06 PM
Wet_Boots's Avatar
Wet_Boots Wet_Boots is online now
LawnSite Fanatic
 
Join Date: Mar 2005
Location: metro NYC
Posts: 39,523
Not enough information. Variables include length and diameter of the supply line going into the meter, and from the meter to your point of connection.
Reply With Quote
  #14  
Old 09-26-2013, 09:41 PM
Mike Leary's Avatar
Mike Leary Mike Leary is online now
LawnSite Fanatic
 
Join Date: Mar 2007
Location: Port Angeles, Washington
Posts: 20,567
I don't get it, the price of a 1" vs 3/4" asembly is minor, it should be run from the setter in brass and a sch 80 mip to tie into the downstream main. Anyone who runs 3/4" mainline joins the hall of pikers and hacks. I wrote the regs for my purveyor and specified unions on both ends.
Reply With Quote
  #15  
Old 09-26-2013, 10:21 PM
Wet_Boots's Avatar
Wet_Boots Wet_Boots is online now
LawnSite Fanatic
 
Join Date: Mar 2005
Location: metro NYC
Posts: 39,523
The price of brass being what it is, I could see a 3/4-inch full-port system shutoff valve and 3/4-inch DCVA with a 12 gpm flow. Of course, it used to be that most 3/4-inch DCVAs were using the same body casting as the 1-inch ones.
Reply With Quote
  #16  
Old 09-27-2013, 08:26 AM
txirrigation txirrigation is offline
LawnSite Senior Member
 
Join Date: Aug 2010
Location: Texas
Posts: 923
Quote:
Originally Posted by Mike Leary View Post
I don't get it, the price of a 1" vs 3/4" asembly is minor, it should be run from the setter in brass and a sch 80 mip to tie into the downstream main. Anyone who runs 3/4" mainline joins the hall of pikers and hacks. I wrote the regs for my purveyor and specified unions on both ends.
We install 3/4 and run a 1" main. We limit all systems to 12gpm. It's had worked great the last 3,000 times we've done it...
Posted via Mobile Device
Reply With Quote
  #17  
Old 09-27-2013, 11:55 AM
AI Inc's Avatar
AI Inc AI Inc is online now
LawnSite Fanatic
 
Join Date: Dec 2007
Location: Southern NH
Posts: 21,226
Quote:
Originally Posted by Mike Leary View Post
I don't get it, the price of a 1" vs 3/4" asembly is minor, it should be run from the setter in brass and a sch 80 mip to tie into the downstream main. Anyone who runs 3/4" mainline joins the hall of pikers and hacks. I wrote the regs for my purveyor and specified unions on both ends.
We don't use dcva's. Cant , illegal here. Difference between 3/4 and 1" pvb is so small its not worth stocking more parts. Not to mention my fingers don't fit inside a 3/4 to rebuild.
__________________
Reply With Quote
  #18  
Old 09-27-2013, 12:20 PM
DanaMac's Avatar
DanaMac DanaMac is offline
LawnSite Fanatic
 
Join Date: Mar 2002
Location: Somewhere in the state of CO
Posts: 13,036
Quote:
Originally Posted by AI Inc View Post
We don't use dcva's. Cant , illegal here. Difference between 3/4 and 1" pvb is so small its not worth stocking more parts. Not to mention my fingers don't fit inside a 3/4 to rebuild.
Can't do dcvas here either.
3/4" PVbs are the most used here, then 1" PVB, then 3/4" RP. Rarely see a 1" RP.
Reply With Quote
  #19  
Old 09-27-2013, 12:55 PM
AI Inc's Avatar
AI Inc AI Inc is online now
LawnSite Fanatic
 
Join Date: Dec 2007
Location: Southern NH
Posts: 21,226
Although I will admit when a rp fails and it will, we replace em with dcva's
__________________
Reply With Quote
  #20  
Old 09-27-2013, 01:17 PM
Mike Leary's Avatar
Mike Leary Mike Leary is online now
LawnSite Fanatic
 
Join Date: Mar 2007
Location: Port Angeles, Washington
Posts: 20,567
Quote:
Originally Posted by AI Inc View Post
Although I will admit when a rp fails and it will, we replace em with dcva's
Obviously, you have no adult supervison, that is crossing the line.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump






Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Moose River Media
All times are GMT -4. The time now is 02:16 PM.

Page generated in 0.07362 seconds with 9 queries