I replaced an interior water ball valve which feeds my vacuum breaker for the sprinkler system. Replacing the ball valve required me to turn off the main water supply and drain the entire house system. Replaced with a new ball valve, turned the water back on but now have low water pressure throughout the entire house. Hot/Cold work just fine, but the pressure is nowhere where it used to be. Pulled strainers on sinks/showers. They are clean. What are my next steps?