Question
The problem statred shortly after replacing our well pump and preasure tank.  Here is what has happened.  I have 21 stations on my sprinkler system, that use our shallow well for watering.  

The solenoid on three particluar stations continue to get stuck.  At first I thought it was due to sand from the well water, but I am almost 100% certain it is not.  Out of the 21 total stations, these three are the only ones that I am having problems with.  I have had a sprikler man out several times.  On his last trip he completly replaced each of the three valve stations, and the problem did not go away.  

If you turn the station on and then on then back to off it will always go off.  But if you run it at the regualr time it is set to run, (10 to 30 min) then it will not shut off on it's own.  

I have heard throught the grapevine that if the preasure on the preasure tank is to high, that the wiring on some sprinkler systems will be effected by this possibly causing this.  The person that installed the new pump and preasure tank is either out of business or does not anser his phone.  

Can you shed any light on this problem.  It is driving me crazy.

Thanks a milllion in advance for your thoughts.

Answer
Hey Gavin, it sounds to me like a wiring problem. When you say the solenoids get stuck, do you mean the valves stay on? I am going to assume you do. The controller sends out 24 volts to the solenoid for the valve it is supposed to open. Also, usually you will have a wire that runs to the pump start relay, that will turn on the pump. This wire that goes to the pump has power no matter what valve is on, so the pump will run no matter what valve is on. If a wire from a valve is shorted or touching the wire that runs to the pump start relay, then this valve will also run anytime the system is on. I would check your wiring before you do anything. good luck and have a great day.