Is Water Drainage Normal or Do I Have a Faulty Valve?
If you system is off and water continues to leak or trickle from the heads you may have a valve problem. Or you simply might have a lowest head seepage problem.
The easiest way to tell if you have a bad valve or a simple seepage/drainage problem is to pay attention to how long it goes on. When your valve turns off water remains in the zone. It will want to run out of the lowest point, drain from the zone and then stop. Depending on the zone this can take from a few minutes. If you want a quick test you can find the lowest head, remove it and let the water flow. There should be a rush of water and then nothing. Simple seepage caused by slope and water left in the zone will stop quickly. A problem with a stuck or failing valve will continue flowing.
Seepage is normal and a small bit is expected. If your yard is flat this is normally not an issue. If you have a noticeable slope to the yard the seepage can become excessive. The simplest fix is to replace the standard heads with heads with check valves, such as the Rain Bird 1804 SAM or the K-Rain 78004-CV-PR. Remember, if it is a steep slope you want to replace all of the heads on the slope. If you have large area it might be worth your while to have a Licensed Irrigator check the system. Other options are available that may serve you better.
If it is the valve then either the valve has trash in the body, holding it open, or the diaphragm is failing. There is quick test and fix for small bits of trash. Remove the lowest head on the line. Now go to the valve and turn the bleed screw wide open so the valve comes on. The valve should come on with a little more flow than normal. Small bits of trash will be blown out the end of your pipe. Turn it back off after a few seconds and watch results. If this doesn’t work you cannot tell from the outside if it is a failing valve or larger trash.
Either way the valve will have to be opened to check. If it needs repair it may be possible to purchase an identical valve, open the old one and replace the internals and top with the new parts. It’s easier than it sounds. Look HERE for a guide.
If you have any questions on servicing the system it is best to have a professional irrigator do the repairs and check the system.
For any irrigation system questions please visit us at Sprinkler Warehouse.