grpark20
New Member
Hello everyone! I am installing my own irrigation system and need some technical help with my GPM for each zone. I am on a well, so I had a very hard time measuring the GPM due to the velocity of the water and proximity to the pressure tank. It appeared as if I could get 10 GPM at 40 psi dynamic, but I do not trust that measurement at all due to it free flowing out of a 1 inch line that is 30 feet away from the pressure tank. My well pump is a 1 hp submersible and rated at 10 GPM.
This is what I have setup so far…I have a CSV installed so my pump runs continuously when any amount of water is flowing after kicking on. I installed a tee with a 1 inch Sched 40 PVC line that matches my incoming well water line. I have a DCVA installed and have a pressure gauge on the down stream side of the DCVA.
Here are more thorough measurements…
Static PSI on the down stream side of the DCVA is 58 psi and the pressure tank is 65 PSI.
I turned on several faucets in my house and measured the total GPM. My dynamic psi on the down stream side of the DCVA was 48 PSI and 50 PSI on the pressure tank, both with 8.78 GPM flowing. I do not know if the pressure is that accurate because at most of my faucets there is ½ inch line. I will say, even thought the dynamic psi reads decent, at the faucets there was a significant reduction in velocity. I am anticipating this loss at the heads, but do not know the math yet to figure out how much.
So, the question I have is how many GPM should I plan for each zone of my system?
I plan on watering very early in the morning so I should be good with minimal pressure for the house. I do have a hilly yard and a full acre with maybe ¾ acre of lawn. I plan on running all rainbird components and after the valves running 1 inch CL200 PVC pipe to everything minus the last 2 feet to the heads. I’ll use ½ inch funny pipe for the last 2 feet. I do have some fairly long runs, with the longest being 450 feet due to not wanting to go under the driveway. Once I get a decent gameplan I’ll build everything on top of the ground for testing, then rent a trencher to bury.
At this point in my planning (see pics) my largest zone is 9.7 GPM and I have 5 zones. I think that may be too much and probably need to go to 8 zones?
What do you professionals say? I have considered sending this to rain bird for planning, but I’d rather get it from the guys that do it everyday for a living. I’ll gladly pay someone for a solid plan if you’re willing.
Thanks,
George
This is what I have setup so far…I have a CSV installed so my pump runs continuously when any amount of water is flowing after kicking on. I installed a tee with a 1 inch Sched 40 PVC line that matches my incoming well water line. I have a DCVA installed and have a pressure gauge on the down stream side of the DCVA.
Here are more thorough measurements…
Static PSI on the down stream side of the DCVA is 58 psi and the pressure tank is 65 PSI.
I turned on several faucets in my house and measured the total GPM. My dynamic psi on the down stream side of the DCVA was 48 PSI and 50 PSI on the pressure tank, both with 8.78 GPM flowing. I do not know if the pressure is that accurate because at most of my faucets there is ½ inch line. I will say, even thought the dynamic psi reads decent, at the faucets there was a significant reduction in velocity. I am anticipating this loss at the heads, but do not know the math yet to figure out how much.
So, the question I have is how many GPM should I plan for each zone of my system?
I plan on watering very early in the morning so I should be good with minimal pressure for the house. I do have a hilly yard and a full acre with maybe ¾ acre of lawn. I plan on running all rainbird components and after the valves running 1 inch CL200 PVC pipe to everything minus the last 2 feet to the heads. I’ll use ½ inch funny pipe for the last 2 feet. I do have some fairly long runs, with the longest being 450 feet due to not wanting to go under the driveway. Once I get a decent gameplan I’ll build everything on top of the ground for testing, then rent a trencher to bury.
At this point in my planning (see pics) my largest zone is 9.7 GPM and I have 5 zones. I think that may be too much and probably need to go to 8 zones?
What do you professionals say? I have considered sending this to rain bird for planning, but I’d rather get it from the guys that do it everyday for a living. I’ll gladly pay someone for a solid plan if you’re willing.
Thanks,
George
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