An unusual situation has started to occur on our automatic valves that have been installed at the newest school sites; 3 elementaries and 1 high school. We use Irritrol Century Plus valves and each of these sites are on domestic water with a booster pump added for the field areas. We'll have a zone stop working where the valve stops firing from the clock. You can manually activate it through both the bleeder screw and the solenoid actuator but not electrically. We've found that by remotely activating the valve and then throttling down the flow control handle the valve will then fire as the problem is corrected. It's almost like too much pressure to the valve is prohibiting it from activating until the flow control is adjusted. Anyone run into a similar situation with other valves?