Hi all, hoping to find some sort of guidance. My sprinkler system is a year old underground rain bird system that covers 17000 sq ft with 8 zones. When I turn a zone on the pressure and flow are great. A couple minutes into the cycle the zone will lose some pressure and have a bad flow. This will continue until there is barely a flow. When the pressure drops my backflow pressure valve spits water out of the top. If I turn it off and start another cycle the same thing happens. Great pressure for a few minutes, and then it loses it. I am on well water with a constant pressure system. Any guidance is appreciated!