Question
QUESTION: I'm in southern CA.  My irrigation system was professionally installed 13 years ago, with valves, timers, and heads replaced over time on an as needed basis.  I抳e noticed over the past few months that a few of my sprinkler valves have real low water pressure when they run from the timer on a program, and also if I run them individually through the timer.  But, when they are run manually by turning the screw on top of the valve, the water pressure is great.  I even switched out one of the valves, but the new one did the same thing.  So I know the valves are ok.  To me this means the water pressure coming in is ok, the pressure going out is ok, the lines aren抰 broken or clogged, and I抦 stumped.  What do you suggest?  Thanks, Karen



ANSWER: Hey Karen, I hope this helps. I would be 99% sure, that the diaphrams in these valves are starting to wear out. The valve will still turn on fine from the controller,but the diaphram is not opening all the way to allow the water to flow properly. When you bleed the valve, If the diaphram is good or bad, it will still open all the way up. You will need to find out which brand and model valve you have, and most any irrigation supply stores should sell just the diaphram. The diaphram is fairly easy to replace. A good website is www.irrigationtutorials.com. this site will show you how to replace a diaphram, or the whole valve. Let me know if I can be of further help, thanks and have a great day.

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QUESTION: Thanks, Jim, but I'm not sure this will solve my problem because I did replace one of my problem valves with a new one and it still did the same thing.  When the new valve was bled using the screw on top it worked fine, but when it was run through the controller the water pressure was very low.  That puzzled me, and made me think it was something other than the valve.  I will try another new valve, but could it be anything else?  Thanks, Karen

Answer
Hey Karen, I hope this helps. When the new valve was installed, was it installed with the water flow in the right direction? If the valve is installed backwards, it could have the same effect you are talking about. Make sure the valve is installed correctly. Normally the controller activates the solenoid, which in turn allows the valve to open. If it was the controller or the solenoid, the valve would not open at all. The only other thing that you could check, is turn the water off,and unscrew the solenoid off the valve body, there will be a small hole in the middle of the solenoid port. Then turn the water back on, and you should get a steady flow of water through this hole. Turn the water back off, and then screw the solenoid back on. If you do not get a steady stream of water out of the solenoid port, put a needle or small nail through the hole, to clean it out. Good luck and have a great day.