A: If the valve is in the open position then it depends on the orientation of the valve. If the valve is horizontal or vertical actuator down then the gate will remain open. If the valve is vertical actuator up then the gate will pull down. If the valve is in the closed position it depends on the size of valve and whether or not a HVA solenoid was installed. If the valve was purchased without a solenoid then it is adjusted to lock-over-center which means that the internal linkage mechanism will keep it closed. If the valve was purchased with a HVA solenoid and is 6″ ID and smaller than it is also adjusted to lock-over-center. If the valve is 8″ ID and larger there is a brass check valve in the solenoid that will maintain pressure to keep it closed only if there are no leaks in the air line and air fittings.