Sprinkler Valve Repair Problems

Hi Craig.
I've got a sprinkler valve repair problem.

The system is on reclaimed water and the water only gets turned on twice a week for a couple hours at a time. The system gets dirt in the valves causing them to have a constant dribble at the heads and stay on at times. Sometimes the valves will close fully and other times 2-3 valves will be leaking or even stay on at times. Owner stated she has had numerous companies clean and even replace the valves previously.

I had looked at the system and flushed the valves which fixed all zones but 1 that still has a slow leak. When the system is running everything checks out. How can dirt keep getting into the valves time and time again without a sign of a broken line anywhere? She said she had her sod replaced a couple years back if that helps with anything. I just don't want to replace valves and have the same problem down the road. Thanks for reading and any info will be greatly appreciated.
Brian

Hi Brian,
The 1st question is "how do we know that it is dirt?" I'm familiar with Alafaya Utilities that supply the water to that subdivision. Sometimes their re-claim tanks run dry (because a lot of people over water). When that happens all that re-claim water "gunk" gets in the supply line which ends up in the sprinkler valve. Nasty!
If this is the case (you did say that you flushed the valves)there are a couple of options.

1. Install a hose bib on the main line at the lowest point and really flush the main line.Even if you employ the other solutions, do this anyway.

2. Install a re-claim water filter upstream of the first valve. This is a common approach. However, they are not attractive (because they stick up out of the ground) and must be hidden with shrubbery.

3. This is the most expensive approach. Install all new "dirty water" valves on the system. Rainbird, Hunter and other sprinkler manufactures make special valves especially for dirty water.Proce the valves before you bid the job because they are much more expensive than your run-of-the-mill cheapo valves.

I hope all is going well with your sprinkler repair business.