Seems a little weird.....is your valve electrically wired to a controller? What happens when the controller turns the valves on an off....which valves operate this system, or perticular zone? What im getting at is that the valve is having trouble completly opening, or .......is the bed rocky? it is possible that there is a little dirt wedged before the first tee.....try this
<b></b><font color="red"></font id="red">Step 1
1. Find the first fitting on that zone after the valve.....dig back down to the fitting,,,,,,,take the fitting off (did you use regular insert tees, or saddle?) and take out the fitting......flush the pipe...and clean out what might be in the fitting...if it is all clear from there....then,,,,,,
<b></b><font color="red"></font id="red">Step 2
Open up the valve....once all insides are taken apart, turn the water on, to flush out the valves completly, and then close the line, and replace all valve fittings......if that does not work let me know
the reason i dont think that therees clogged heads, or nozzle is that you say that sometimes they do work.....??? Let me know
Good Luck!
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