Tips & Tricks

From the Aqua~Flo Supply Staff

Rule of 4’s & 9’s as pertaining to pipe sizing in an irrigation system

This is a good rule of thumb system for sizing mainline & lateral pipe in a residential irrigation system

With PVC pipe as flows increase, so does velocity in the lines. Most irrigation applications use 5 feet per second as the maximum velocity allowable (velocities in excess of 5 fps are generally not used due to increased friction loss as well as increased chance of water hammer.) Using the below system you will always be at an acceptable velocity.

Sch 40 PVC Pipe (Rule of 4’s)

1/2” 4 Gallons Per Minute Maximum
3/4” 8 Gallons Per Minute Maximum
1” 12 Gallons Per Minute Maximum

As you can see each time the flow increases by 4 Gallons per minute a change of pipe size is necessary. If the flow decreases by 4 GPM a change of pipe size can be done, but it is not always necessary as the velocity in the pipeline decreases with flow reductions. Pipe is generally sized down due to economics.

Class 200 PVC Pipe (Rule of 9’s)

3/4” 9 Gallons Per Minute Maximum
1” 18 Gallons Per Minute Maximum
1 1/4” 27 Gallons Per Minute Maximum

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Troubleshooting controller/valve issues #1

Your controller seems to work fine, but none of the valves come on:
The probable cause is a short in a solenoid or a broken common wire. The most likely cause, is a short in a solenoid. This will short out and blow the fuse in the controller and nothing will come on. Simply replacing the fuse will not fix the problem, you will need to determine which valve is causing the problem. I suggest running the clock through it’s cycle, then when the fuse blows on the problem station, that is the valve that needs to have the solenoid replaced. Replace the solenoid, and install new fuse, and your problem should be solved.

To test for a broken common wire:
A simple troubleshooting technique is to run a temporary wire on top of the ground to the first valve. Connect it to the clock and tie it in to the valve. Then run the controller, the valve should operate normally. If it doesn’t then it is not a broken wire, it is another problem.

Irrigation comes on at different times of the day.

First: Check the current clock time, because there may have been a power failure, and reset. Install new batteries, because they should have kept the current time.
Other possibilities are:
•Phantom programs due to a glitch in the program. If this is the case remove the battery, and turn off the power supply. Reprogram as needed, and test the program to make sure it functions properly. Add new battery, and you are ready to go.
•Check for days on, and start times for all programs. Sometimes you may find that program B or C has accidentally been programmed when you only wanted program A to run.

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