Help! Where Are My Sprinkler Valves Located?




One summer after I had moved into my new house I found that the sprinkler system didn't work correctly. I noticed that when the water was not on the sprinkler heads still leaked water. I figured that the values were probably dirty and were not closing properly. So I set out one morning to bleed the values and clean them up as necessary. The only problem is I had no idea where the valves were located. I knew they were under the ground somewhere in my yard. I looked and looked but could not find them. I used a metal detector, probed the ground, everything. Then I had an idea about building the following circuit.

The valves make a clicking noise when their solenoids open and close the water valve. I figured that if I turn the valves on and off (after turning off the water supply) and listen then I might be able to hear the valves operating. The problem is that I didn't have anybody that would stand around flipping the switch on/off while I walked around the yard listening. So I built this circuit and connected it to the sprinkler system. Within two minutes I found the valves and had the leaks all fixed.

Parts List: wire, (AA,AAA,C,D or 9V) batteries, toggle switch, relay, leds, NTE955 timer chip, 1k resistors, 5k resitors, 4k resistor, 100uF capacitor, battery clip or battery pack holder, circuit board.

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Step 1: Tools Used for This Project

The tools used for this project are as follows:
Digital Multimeter
Soldering Iron
Soldering Flux
Magnifying Glass
Wire Cutters
Wire Stripper

Step 2: Project Schematic

The wiring schematic is shown in the picture.

Usage Instructions:
1. turn off water to sprinkler system
2. connect valve across relay (24VAC systems)
3. turn on circuit by closing SPST switch
4. turn on sprinkler system and select valve that is connected to the circuit.
5. LED light on circuit will blink alternately.
6. relay will open and close one time per second.
7. sprinkler valve will turn on one time per sec.
8. listen to ground and you should hear valve turning off and on.
9. if you still can't find valve then increase timer circuit frequency by changing values of R1,R2 and C per the equations shown below. Increasing frequency will make solenoid hum louder.

Step 3: Solder Part Together

Place the parts on the project board and solder the wires to each part per the schematic. Put flux on each solder joint prior to soldering.

Step 4: More Pictures of the Completed Project

At the control panel for you sprinkler system disconnect the wires from the switch that control the valve you are trying to locate. Insert the Sprinkler Valve Finder inline. The circuit basically is taking place of the control panel switch. Once connected turn on your sprinkler system like normal (remember to turn off the water first). Now flip the SPST toggle switch on the circuit. Your valve will not turn on and off at the same rate the LEDs on the board are flashing. Go out into your yard and start listening.

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    11 Discussions


    10 years ago

    This project looks awesome but there isn't enough documentation of you actually making it to be a full Instructable. There are two things which you could do. 1) If you happen to have images of you making your project you can create some more steps, add those additional photos into your Instructable and then republish your Instructable. 2) If you don't have any more pictures of you working on your project, that's ok too. That just means that your project is better suited to be submitted as a slideshow. Your images are already in your library, and you can use the same text that you have already written for your Instructable so it should only take a few minutes to create your slideshow and show the world what you made! Thanks for your submission and let me know if you have any questions along the way.


    7 years ago on Step 4

    ANyone got a schematic for the thing that has a speaker on it ( I am not sure what its called ) that makes a sound the closer you get to the valve your trying to find. Its basically a detector that magnifies the sound through the speaker like a homing reciever.


    9 years ago on Introduction

    I found another easy method. Hook up a wire from your turn signal light bulb socket of your car and connect it to each solenoid lead...each time the turn signal goes on, the solenoid will also click ! 

    thb43Callum Snowden

    Reply 10 years ago on Step 4

    They are cheap, fit the specs, and it works. Please teach this amature a thing or two and explain why another relay would be a better choice for this project.

    Callum Snowdenthb43

    Reply 10 years ago on Step 4

    I'm not an amature, I have built many a circuits in my life. I was only saying that the reed relay might not be able to handle the solenoids current, because you might not know the solenoid's current unless you measure it. So if you measured the solenoid's current then chose a suitably rated relay for the job, that's the point I was trying to get across to you.It was only a suggestion.

    thb43Callum Snowden

    Reply 10 years ago on Introduction

    thanks for the info. Its a good point that the size the relay should be sized to the solenoid's current.


    10 years ago on Introduction

    Did you ever find your valves? If you did was that the problem?