Go to your control box and open the panel that covers the wiring. By identifying which zone never shut off, pay attention to the corresponding color wire. Once you know the wire color, go outside to your solenoid valve box and find out which solenoid valve is malfunctioning. The valve may be malfunctioning, or it could be that some particulate matter is stuck between the closing apparatus of the valve, keeping it open when not energized. Open it up, clean it out, see if it continues to leak. If it does, just replace the valve.

Hi eriocaulon,

Thanks for responding so quickly and with detailed information. I appreciate that, but my sprinkler system is different. The six inline valves are located in different underground spots in the yard, not in one place. The wiring to each valve is a two-wire cable with no color coded multiwire cable involved. So far I have not been able to identify which of the solenoid valves is malfunctioning. I replaced two of them that appeared to be possibile problem ones but that did not help. I was hoping to be able to turn each valve off manually to help identify the problem valve. As I understand it that should be possible by turning the small knob on the top of the valve. I have turned all of those knobs first all-the-way clockwise but that did not shut them off. Then turning them all counter-clockwise did not work either. I am trying to avaoid repacing those valves one-by-one to try to solve the problem.

(By the way, I did not install the system.)

Your valves likely dont have a flow control on them which in most cases would allow you to isolate that valve. Most of the time when a valve fails open, you can hear the water flowing through it. You can use a stethiscope to listen to the water flow through the valve if you cant readily determine which one has failed open.

All Wet

I wonder how old is "old." Check out rainbirds current line of valves and see if any are similar to what you have.

Here is a link that might be useful: Rainbird valves

All_Wet and eriocaulon,

Thanks for more thoughts. I have no idea how old our system is, but we have lived here ten years and it was installed well before we arrived. I appreciate the link to Rainbird valves. That was thoughtful of you. I had checked Rainbird's site as well as Lowe's and Home Depot before posting here. I had hoped that I could find a valve with a "body" similar to these old ones so that I could reuse the old base and not have to cut the 1" pvc. However all of the current "advanced designs" are such that I cannot do that.

Since all of the valves are 18" underground, with my poor hearing, I would never be able to hear the water running in the defective valve though that idea makes sense. I never thought of a stethiscope. That is also a good idea.

I finally "flipped a coin" and selected one valve and replaced it with a nice modern one with a manual On/Off Bypass Lever. That seems to have done the trick, at least there is no evidence of any water flow now while the system controller is not on, and that was what I was trying to do. So I think the job is done. Thank you for taking the time to help!

If one of the valves isn't getting juice due to a bad connection, you can use a locator. Those are rented out. Are your valves actually buried or are they in valve boxes? If the valves are truly buried, you need to update your system. Having buried valves makes maintenance a chore (lots of digging) and very hard to troubleshoot (the problem you just had). I think it would be worth it to dig them all up and put valve boxes in so that you can access these guys much easier. It might even be worth it to pay someone to redesign your system so that all of the valves are on a manifold assembly in one large valve box with new valves. Note that the valves sold by Home Depot are probably not as good as a professional gets from a wholesaler, even if it does say rainbird or toro on it. Good luck! Water is the most important part of keeping a lawn looking great!

Denver Dude,

Thank you for sharing your thoughts. They are all good and useful. My inline valves are in individual valve boxes. The actual boxes are not deep enough to cover and protect the valves. So there is a piece of 6" PVC sitting upright over each valve. Each of those pieces of PVC serves as an "extender" and the base for a valve box. So, a valve box and cover is at the surface. When the valve box cover is removed, I have to reach down the distance of the valve box and the PVC extension to reach the valve.

I agree that it would make sense to design and install a completely new system. However, given a number of personal factors I do not want to do that right now, but I do appreciate your advice.

I am pleased to say that the valve I replaced yesterday seems to have solved the problem. So, with my fingers crossed, I am taking a vaction from the sprinkler repair business and returning to gardening. Thanks to all of you for your help.

My question is if the valve should be in the on position and the timer then turns it off and on according to settings? I thought everyhting was properly hooked up but, the sprinklers only come on when i turn them on manually at the sphenoid box outside. Then I connect the timer and turn it on and they stay on and do not turn off through the timer. I checked the wiring and the common seems correctly connected but I may have someone use an ohmmeter to make sure. I have 8 sprinklers running at 2 stations and a 3rd that does not work for whatever reason (I have to look around to see) If I turn the valves off outside (flip the little plastic tab in the rear of each) then I do not hear the water flow, but since I have never seen sprinklers run on an electrical timer, I cannot understand how the valve will be powerful enough to stop the flow like the valve shutoff tab even though this is what I have been told should happen.