Question
Hi Jim,

I have a 10 year old system.  When I turned on my sprinkler in test mode or regular program mode my Zone 4 stays on and doesn't shut down even when I put the controller in the OFF position. It also seems that all the zones are running just not at full pressure.  Any ideas ?

Thanks,

Jim

Answer
Hey Jim, more than likely, the #4 valve is stuck on. Either the diaphragm has gone bad and needs to be replaced, or the plunger in the solenoid is stuck in the up position. Since this valve is running when the other valves are turned on, you will not have enough water pressure to run more than one valve at a time, and that is why the other zones are not working properly. The solution is to either re-build the #4 valve, or replace the #4 valve. Go to www.irrigationtutorials.com and this website will show you how to either replace or re-build the valve. Good luck and have a great day.