I just installed a new tank, pressure switch (20/40) and pressure gauge on my well. For the 20/40 switch, the tank was pressurized to 18 lbs as directed by the manufacturer. When I turned on the power, my tank would only pressurize to 33 lbs so the 4'' submerssible pump keeps running. What would cause this?

Why did you change out the tank, etc? Just looking for some clues.

It sounds like your pump is going away. How old is it?

I changed the tank because the ballast broke. The pump is near 15 years old.

When you set the bladder tank did you shut the power off and bleed the system down before you made the adjustment? Back to you, Tom