Hi! This U.S. Guage Air Volume Control (see above link) will not shut off my father's Myers shallow non-submersible well pump unless the orifice of the U.S. Guage air volume control is plugged. Otherwise, the air pressure will never climb enough to trip the pressure switch (set at 40 PSI).

The U.S. Guage Air Volume Control is attached to a simple bladderless tank. In order to keep the pump from running continuously , I had to seal the orifice with a few wraps of duct tape around the control. What is the answer here? I need help! Thanks!