How to Adjust a Bladder in a Tank Well Pump

Pressure tanks for home private wells contain a rubber bladder.
The bladder aids in maintaining pressure to the water system. Over time, the bladder may lose air pressure. When this occurs, the pump may operate erratically. Most rubber bladders must have an inflation pressure between 30 and 40 lbs. per square inch (PSI). A basic air pressure gauge, like the one used for measuring automobile tire pressure, is used for the measurement. Add compressed air to fill the bladder, much like inflating an automobile tire.

Step 1

Remove all electrical power from the water well pump. Shut off the circuit breaker or pull the fuses that supply power to the well pump system.

Step 2

Drain the water system. All water pressure must be removed from the pressure tank. If the water system has a pressure gauge on the tank, the gauge must read 0 PSI. If there's no gauge, wait until all water has been drained.

Step 3

Search for the air filling valve on the water pressure tank. Typically it is on the top of the tank. The air filling valve looks identical to an automobile tire valve or a bicycle tire valve.

Step 4

Press the end of the pressure gauge on to the air filling valve. The gauge should read between 30 PSI and 40 PSI.

Step 5

Add air to the bladder in the pressure tank, with the compressed air source, if the gauge reads less than 30 PSI. Check the pressure again.

Step 6

Remove air from the bladder if the gauge reads greater than 40 PSI. Push in the small pin in the center of the filling air valve. You will hear the air escaping. Check the pressure again.


  • If the bladder does not hold any air pressure after attempting to fill it with a compressed air source, the bladder may have a hole in it. There is no access to the air bladder for service or repair. The pressure tank must be replaced.