Actuation of the detection system opens the pre-action valve, which permits water to be discharged ... of the water may lower the smoke level in a room where the fire is burning, the sprinklers also ...

Turn the valve to the side until it is perpendicular ... testing to ensure that water moves smoothly through the system if the fire sprinklers are ever activated in an emergency.

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 going back into the drinking water inside ...