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JDub
12th May 2006, 12:36 PM
Hi all,

Just in the process of installing my irrigation system and am getting some conflicting advice as to how many / and the placement of my lawn pop ups.
They are rainbird 1800 series and have a 3.6m radius (12ft).

Below are the three options. One design only needs one station, the others need two.

Thoughts?

Cheers
Joel


1) 7 pop ups, 1 station

http://www.users.on.net/~joelwillis/lawnarea%5b2%5d.bmp

2) 9 pop ups, 2 stations
http://www.users.on.net/~joelwillis/lawnarea%5b1%5d.bmp

3) 12 pop ups, 2 stations

http://www.users.on.net/~joelwillis/lawnarea%5b3%5d.bmp

KevM
12th May 2006, 02:36 PM
Go with option 1.

Lay them all out on top of the ground, connect up and turn on. If you don't get full coverage, experiment with your placement/placings. The pipe is cheap, you don't want to be digging trenches for no reason.

Remember that your water pressure will also decrease in times of maximum usage. So place a little closer than your results would suggest to ensure all edges get coverage.

Kev M

DanP
13th May 2006, 12:44 AM
Each pop up should almost reach the next one for correct coverage. When you design your layout, lay them out about 12' apart. You need to try out how many pop ups your water pressure and volume will run to know how many stations you will need. Err on the side of too many stations.

Dan

DanP
13th May 2006, 12:46 AM
Option 3 would cover the area well. You need to know if your pressure/volume will handle 6 pop ups per station.

Dan

namtrak
13th May 2006, 06:51 PM
Whats your water pressure? Turn an outside tap on full bore (with no fittings) and then slip a 10/9 litre bucket underneath it and time how long it takes to fill. That will give you a litres per minute idea. Most houses are between 25 and 35 litres per minute.

From that you can extrapolate how many sprinklers to use.

Is it going to be an automated system?

JDub
13th May 2006, 08:38 PM
Whats your water pressure? Turn an outside tap on full bore (with no fittings) and then slip a 10/9 litre bucket underneath it and time how long it takes to fill. That will give you a litres per minute idea. Most houses are between 25 and 35 litres per minute.

From that you can extrapolate how many sprinklers to use.

Is it going to be an automated system?

Yes, fully automated. Think I will go with option 2 as that gives me almost head to head on most areas and isnt overkill.

Takes about 18 seconds to fill a 9 litre bucket. So without getting out the calculator or hurting myself too much, thats about 30 litres a minute.;)

Grunt
13th May 2006, 08:50 PM
Have you considered below ground irrigation?
http://www.biolytix.com/ourProducts/irrigation.htm
No heads to get clogged, no evaporation. Much better.

arms
14th May 2006, 07:20 PM
1) 7 pop ups, 1 station

http://www.users.on.net/~joelwillis/lawnarea%5b2%5d.bmp


this is the go ,from my experience in my own yard with these damned things option 1 is right ,as you only have 30 litres of water to play with i would suggest breaking up the heads into groups and spraying in a sequential pattern to suit your flow rates

namtrak
14th May 2006, 08:16 PM
Okay work on 25 litres per minute.

Now each sprinkler needs to reach each other one, otherwise you will end up with dead patches around the sprinkler heads. Depending on what sort of lawn your putting in (kikuyu, fescue, buffalo, couch etc) I think you are probably looking at your second option, however you could get away with 1 station. If you use a 6 station controller box (my recommendation given the small increase in price and greater room for expansion) then using 2 stations would be simple.

Also there is a little hex screw (make sure your supply gives you the tools that go with them) that you can adjust to damper the spray as well, which gives you a range outside of just 3.6m

How many other stations are you looking at? Garden beds, other areas of lawn etc. Not that it makes any difference, more that you can get whole of system advice ;)

Make sure you (a licensed plumber) install a back flow and a master controller. Both very valuable and required backups.

JDub
15th May 2006, 10:07 AM
Cheers for the advice,

I actually contacted my uncle over the weekend (who is an irrigation plumber). He has suggested that option 1 will do the job fine but if I really want I could go with option two but doesnt feel it is very necessary. :shrugs: :confused:

I have already purchased all the gear (six station controller, dual back check valve etc) and my uncle will be tapping into the mains and installing the back check valve and stop cock for me. ;)
From mains to s. valves will be 25mm PVC, from valves to garden drippers 19mm poly and from valves to lawn pop ups 20mm PVC.

A couple of weeks ago I managed to pick up the brand new six station outdoor controller, 5 solenoids, dual back check valve, rain sensor, and 12 rainbird pop ups off ebay for $300... not bad considering the RRP of the controller is $239 alone.

Other than the lawn there will be four other stations, 3 garden beds and 1 pot plant station.... all are on drippers. :D

namtrak
15th May 2006, 10:58 AM
That all sounds on the money. Get your uncle to show how to pull apart and adjust the sprinkler heads. You'd be surprised (or not) on how many times I go to a job which takes about 2 minutes to fix. The trickiest one is knowing how to clean out the solenoids if one gets a small stone in the plunger.

Cheers