Air level control meaning like a leaking air bladder tank?
Greyhound

IF you have a air bladder tank then you don't have an air level control.

A leaking bladder usually results in a "water logged" tank as the air in the
tank dissolves in the water.

Too much air in the tank has to be caused by air coming into the water that
a properly working system would not permit or the system that vents excess
air (air volumn control) not working properly.