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.
Help with valves in system....and hills
Good afternoon,
I live on 2 acres, the lot is about 600 x 300. The height from front to back (elevation change) is about 100 ft. When I bought the house the irrigation system was in. Most of the valves ate at the house , about half way up the hill. Most of the rotors and drip are above the house. I just read that the Antisiphon valves that are installed must be installed 6 higher than the highest sprinkler. This is not the case
.. The highest sprinkler is about 20 ft above the valve. What should I do????
Thanks
Tim
Hard to tell without seeing the site in person. If you are lucky enough to have lots of pressure, then another backflow preventer can easily be cut into the supply. Where you live figures into your choices. The one device to fit any situation is the RPZ, and you lose at least 10 to 15 psi when it's installed.
I am on a well so the presure is between 30 and 50 as it cycles on and off. I am running roters (Orbit and hunter). I would guess that 10 to 15 lbs of friction losss that is not an option..... howmuch back presute and a 3/4 valve with back flow handle?
TimCA
Plan B is to replumb the uphill stuff so the antisyphon valves are at the top of the property, or wherever they can have the needed elevation difference. Lots more work, but no RPZ losses.
Be careful with this elevation change. By the time you get to the top of the hundred feet you will lose 44psi. The formula is .44psi/Ft of elevation change. We have incountered this problem before and you either install the rpz, 2 backflows or a non dumping backflow(not code in new england!).