I've had the same problem as hbaird a couple of times in the past fifteen years. My tank doesn't have a bladder either. Common in this area as a way of eliminating sulphur smell by letting the water contact air in the tank.
The float hbaird refers to is called the air control valve. It is adjustable/replaceable, and regulates the amount of air that will be let into the tank as the tank level drops and then goes back up. In my case, the iron in the water cakes on the float mechanism causing it to stick.
If the air control valve isn't working properly, you can get quite a lot of air in the pipes. I had enough air to turn my shower into a "mister" at some times.
Ira
The float hbaird refers to is called the air control valve. It is adjustable/replaceable, and regulates the amount of air that will be let into the tank as the tank level drops and then goes back up. In my case, the iron in the water cakes on the float mechanism causing it to stick.
If the air control valve isn't working properly, you can get quite a lot of air in the pipes. I had enough air to turn my shower into a "mister" at some times.
Ira