The regulator is closed when the adjusting screw is turned out (counterclockwise)?

• A. True
• B. False
• C. Sometimes
• D. Never

Answer: (A)

In a gas regulator, the adjusting screw changes the spring force on the metering valve, which determines how easily the valve opens to allow gas through. Turning the screw clockwise increases spring tension, which typically raises the pressure required to open the valve and reduces flow. Turning it counterclockwise (backing the screw out) reduces that tension, causing the valve to close more readily and eventually stop flow. So, turning the adjusting screw out (counterclockwise) closes the regulator.