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View Full Version : How to keep pressure up with Multiple Sprinklers off of one spout???


Watwood
07-18-2006, 04:56 PM
I have 4 sprinklers I need to run off of out spout. If I got a 4 way splitter, that would mean 25% of the pressure would be evenly distributed between the 4 sprinklers, correct?

Alright, well what if I put the sprinklers in a series, aka, one hose coming out of the spout hooked to the first sprinkler, then a hose running from the 1st sprinkler to the 2nd, etc. etc. until the 4th sprinkler. Would this keep the proper pressure up for all 4 sprinklers, or would the pressure be 100% at the first sprinkler, 75% at the 2nd, 50% at the 3rd, and 25% at the 4th?

Thanks

newz7151
07-18-2006, 05:39 PM
I am not in the biz, but unless you are running like a 1" hose, with about 25-30lb in it, I don't think you will have enough pressure OR VOLUME to run 4 sprinklers like that at one time.

The irrigation techs can probably respond better if you post this in the irrigation forum also.

BSDeality
07-18-2006, 05:40 PM
the best way to accomplish this is with a 2 or 4 way manifold. your water pressure will determine how many zones you can run at once. I recently did a house with 3 zones off one spigot and 1 off another, each had two sprinklers on it. I set up portable irrigation timers using a 4 way manifold and a splitter on the other one (wanted to leave the homeowner a hose hookup at each one if he needed it for something else).

ed2hess
07-18-2006, 06:23 PM
A better way to deal with a manual water situation like this is to use the walking device that follows the hose. That way you can do a large area without moving hose. I guess you are talking about manual not designing a sprinkler system?

Watwood
07-18-2006, 07:40 PM
I am talking about a cheap way to water my yard for the time being. I can't afford a true irrigation system for this season, but will have one for next season.

This will simply be a hose and sprinkler setup using sprinklers found at Lowe's:

Gilmour Sprinkler (http://www.lowes.com/lowes/lkn?action=productDetail&productId=99640-306-999ZSGF&lpage=none)

I was thinking about running one hose from the spigot to a central location in the yard, then splitting it into two equal length hoses. Each one of these splits would feed two sprinklers. I would just simply turn the knob to turn one two of the four sprinklers at a time.

BSDeality
07-18-2006, 07:43 PM
I was also talking about a temporary watering system, not an inground system

Watwood, what I have found is the cheap plastic sprinklers work better on low water pressure. I have the brass ones similar to what you linked and they require more water pressure to operate.

hmartin
07-19-2006, 06:01 AM
I have 4 sprinklers I need to run off of out spout. If I got a 4 way splitter, that would mean 25% of the pressure would be evenly distributed between the 4 sprinklers, correct?

Alright, well what if I put the sprinklers in a series, aka, one hose coming out of the spout hooked to the first sprinkler, then a hose running from the 1st sprinkler to the 2nd, etc. etc. until the 4th sprinkler. Would this keep the proper pressure up for all 4 sprinklers, or would the pressure be 100% at the first sprinkler, 75% at the 2nd, 50% at the 3rd, and 25% at the 4th?

Thanks
You are going to have a problem running 4 sprinklers off one spout. As you use more and more flow, the pressure will fall off and you will be limited by how much flow you can get out of one spout, and this will depend your line pressure. The traveling sprinkler is the best idea. Using 4 hoses for 4 sprinklers all ran to a splitter at the spout is second.

dfischer
07-19-2006, 09:18 AM
Much, and I mean like lots, of it will depend on your internal plumbing. You do face a pitced battle. In any event:

I have 45 PSI static, 5 spigots, and can run over 5 gpm each all on at once. So I can run all 5 spigots at once. Dual spigots is a LOT better idea then a splitter...

I've become a fan of melnor. They seem to have a better range of products that I needed for width, timing, and low water pressure use. Examples:

Melnor has a dual zone automatic timing. Of all I tested I found it to have the least water reduction. Now I get a split at the spigot and can turn it and off by time, so I stagger their run times.

if you must use 1 spigot, and can't use a rain train or similar moving tractor, the cheap adjustable width plastic melnors @ home depot seem to work the best on low pressure.

You'll need to use 3/4 hose to your downstream Y split.

I do run two of the above melnors off of one Y, off of one of the dual port timers I mention, so you can do what you mention. BUT, there reach and width is reduced. In fact, I have their width set a bit narrow. They cover about 50% more then 1 would have alone.

If you have more PSI then I do YMMV.

Make sure you use of the hi-capacity Y splitters.

i know of no 4 port manifold that can flow enough water to work well...

MarcSmith
07-19-2006, 09:40 AM
I have the large gilmour at my house. it will solid move some water. the stream of water is about the diamater of a #2 pencil and I would not count on running more than one of them off of a single hose. I tried running the large gilour and the small one and there was not a good water dispersion for either of them when hooked in series. I was not able to try to hook them in parallel...FWIW


Marc

Critical Care
07-19-2006, 10:10 PM
What Marc said about this Gilmour sprinkler is probably true. Unfortunately you do not have enough information to make an accurate assessment. Typically, in the irrigation design business, things are calculated out from specific data – which in your case you do not have. So… it’s just a guess, and my guess is that for the price of those brass impulse heads, you could do better with something else. And yes, the lawn tractors, lawn trains, may work out better for you – as they did for my neighbors until I installed their own irrigation systems.

Gilmour states “up to 106 feet diameter”, but this is probably with 60 psi, and if you don’t have that then you’ll get less coverage. With the size of nozzle that Marc said that this Gilmour has, I’d guess that at 50 psi you might be looking at 7 or 8 gallons per minute being used by one of these sprinklers. Double that for two heads. So you’d likely be having 14 – 16 gpm flowing through whatever size of garden hose you have. Even if you have a 1” garden hose, this amount of water flowing through it would cause friction, and friction causes a loss in psi. If you’re dead set about trying this, you might be able to run one head off of your front hose and spigot while running another head off of the back hose and spigot. Who knows… Some homes can’t handle 14 – 16 gpm. I had to design my own irrigation system at 10 gpm.

Watwood
07-20-2006, 09:58 AM
I wasn't dead set on this setup, I just needed something QUICK because we have been in a drought and the sod was on its last leg.

Luckily I only needed two of the X-Large Gilmour heads where I originally thought I would need two X-Large and two Large heads to cover the whole FRONT yard. So, now I have the two X-Large Gilmour heads on the FRONT lawn running off of the spigot on the north side of the house, and two Large Gilmour heads on the SIDE lawn (the house is a corner lot) running off of the spigot on the south side of the house. I simply turn on one of the heads on each side of the house at one time and the pressure seems to stay up just fine. After 30 minutes of so, switch the splitter on both spigots to the other heads to cover the rest of the yard for 30 minutes.

I guess the whole point of this setup is ease of use. All I have to do is walk out in the morning and turn two knobs on the splitters, 30 minutes later, turn those knobs off and open the other ones. Simple as that.