PSI and GPH

Central Texas, TX(Zone 8b)

Hello,

I have redone my drip irrigation system. Since the old one way was so labor intensive I added a timer, pressure reducer, and filter. Question is that my system seems to have a bit of low pressure. By that I mean the sprayers don't spray very far once I extended the area. Can I cheat a little by taking off that pressure reducer? I checked at the hose bib and I believe it read 80 psi. The manufacturer suggested adding another zone to the mix via the little handbook that's available at the store. Also they recommend a maximum of 220GPH. But it seems to make since doing this to me. Any suggestions?

Thanks for any help.

Dean

Everett, WA(Zone 8a)

80 psi is pretty high pressure. I recently learned that many drip fittings need hose clamps above 20 psi. If you remove your pressure regulator, and multiple hoses blow apart, or sprayers jump out opf thier hoses ... then that would have been a bad idea!

Maybe replace your pressure regulator with a higher-rated model, like 30 psi instead of 20 psi?
Or use pressure-compenstating sprayers or sprinklers where the pressure is too low?
Spave them closer together where you are not getting enoguh water?

Clean all filters?
Check for kinks?

If lines are coupled using "barb" fittings that stick INside the hose, , those restrict the inside diameter. There also exist "compression fittings" that go around the OUTside of a hose, and those don't restrict the flow. But the size of compression fittings must be exactly matched to the OD of your hose. One company's compression fittings might only work with that company's hoses!

Maybe use larger diameter hose on long runs, and/or after each regulatior?
The flow-related pressure drop in a line depends on its length and diameter and the GPM trying to flow through it.

Are you trying to push water uphill? That's hydroSTATIC pressure loss, I think. If you have much slope, consider running the 80 psi line all the way around the yard, trying to bring it to the HIGHest points you can. Then attach the pressure regulators at the high points of drip lines, so that the weight of the water in the drip lines, running downhill, will be ADDED to the water pressure at the spray heads instead of subtracted.

Can I say that more comprehensibly? If you currently have 20 PSI at the bottom of a 12-foot tall hill and run hose uphill, you will have less than 15 psi at the top of the hill. You lose 1 PSI every 2.31 feet of height ( 0.433 PSI per foot ).

But if you put the 20 PSI regulator at tghe TOP of the hill, you will have over 25 PSI at the bottom. The difference between 20 and 25 PSI may mean less to a sprayer than the difference between 20 PSI and 15 PSI.


I hope any of that is helpful - you probably already know most or all of it.

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