How to recharge a pressure tank:  TEST Sometimes after a few years of use the pressure tank will lose internal pressure and not empty out all of the water inside the tank. Pressure tanks can last from 3 to 5 years, depends upon water quality and environmental conditions. Here is a way for you to re-pressurize the tank. Steps to re-pressurizing tank: 1. Turn off water to the unit. 2. Turn off tank ball valve. Open faucet to release any remaining pressure 3. Remove tubing from tank ball valve. 4. Remove tank from under sink and turn the tank upside down in the sink. 5. Open tank ball valve and let tank drain. Sometimes it can take 30 minutes for all the water to drain. You can speed up the draining process by adding air into the tank. If all of the water does not drain out of the tank, it means that the bladder inside the tank has leaked and cannot be repaired. This will happen to all bladder tanks will eventually. Another indication is if water comes out of the air valve. 6. Once the tank is empty, use a tire pressure pump to pressurize empty tank with 7 to 9 PSI with the tank ball valve still in open position.  This puts a cushion of air around the bladder. 7. Re-install/re-attach tank. AWI warranty: one year full replacement. Second year get 50% discount. Third year 33% discount.