If your sprinkler has manual drain valves, also shut off the valves on the backflow preventer. A backflow device, typically located near the water main from which the sprinkler water is drawn ...

Close the backflow valve to prevent air from escaping in ... Sprinkler System Some underground automatic lawn sprinkler systems require you to drain the pipes manually, rather than blowing the ...

Open it up and look for the drain valve. Turn it off by turning the valve to the right. Cover box back up. Now, go to your back flow preventer to keep the water from your sprinkler system from ...