Push in and rotate cylinder valve knob clockwise to close. When cylinder valve is fully closed, open purge valve slightly to vent residual air pressure from system. As the residual air pressure vent from the system, the remote pressure gauge needle will swing from “FULL” and move to wards “EMPTY” band (see Figure 3). The VIBRALERT end of the service indicator alarm shall actuate. The Bell end of service indicator alarm shall ring one or more time. The Beacon Alarm, if installed, shall begin flashing.