Checking the bladder in your well tank is important if your well pump is running frequently with only a small amount of water being used. The well tank is used to store water for use between pumping cycles. When the well pressure tank is not working properly the pump will run frequently on short cycles and burn out.
There are two basic types of well pressure tanks, which you may find in your home, the first being a tank, which does not have a bladder and the second, which has a bladder. The non-bladder is easily recognized by its typical galvanized steel construction, lack of an air valve on the top of the tank, and an air control valve mounted on the side of the tank which controls the air/water level in the tank. Non-bladder pressure tanks require more frequent maintenance and replacement with a bladder type pressure tank should be considered. The bladder type tank is easily recognized by its painted steel construction, and having an air valve on top of the tank similar to an air valve on a tire. The bladder tank will have a single pipe into the tank and will not have an air control valve mounted on the side. Some of the typical names you will see on the tank are Amtrol Well-X-Trol, Well-Rite, Flexcon, WellMate, and Sta-Rite, but there are many others as well. I personally favor the Amtrol Well-X-Trol, and the Flexcon and there are many that I would avoid such as Flo-Tech.
Bladder tanks have two separate sections of the tank separated by the rubber bladder. The air section should be pressurized when there is no pressure on the water side of the system to 2-psi less than the pressure where the well pump turns on, if the system has pressure the tank will read only the system pressure and not the air pre-charge. When the well pump turns on the pressure on the water side of the tank increases and water flows into the tank and to wherever you are using water, until enough water has flowed into the tank to allow the system pressure to reach the pressure at which the pump cuts off. The water then flows out of the tank until the low-pressure setting is reached, and the pump turns on again. If the air pre-charge is not high enough the tank will over fill with water or, become waterlogged, and the water will not push out of the tank, this will cause the pump to short cycle, turning on virtually every time water is used, and cause the pump motor to overheat and burn out. If the tank air pre-charge is set too high not enough water will enter the tank and the pump will also short cycle.
To check the pressure on your well pressure tank and refill the tank you will need a tire pressure gauge, and an air pump. The first thing you should do is make sure that you know the pressure at the point where the pump turns on. Make sure the pressure gauge on your well pump system is working correctly, I like to lightly tap on the gauge with my fingers to make sure the gauge is not sticking giving a bad reading. Your air pre-charge will be 2-psi less than the pressure where the pump turns on. While the well pump system is at its maximum pressure I go to the air valve on the top of the tank. Sometimes the air valve might have a plastic cover that has to be removed first to see it. I press the pin in the center of the valve and see what comes out. If air comes out the bladder in most cases is good. If water comes out the bladder has failed and the tank requires replacement. If the bladder is bad it is not an emergency where you are without water, you may wait for a weekday or, until payday, or even a little longer. But the tank does need replacing, once the bladder has failed the air pre-charge will be absorbed by the water, making frequent recharging necessary to avoid damaging the pump. The air section of the steel tank will also start to rust and water quality will start to suffer. If the bladder has failed simply pump enough air into the tank that the cycles are normal length and get the pressure tank replaced as soon as possible.
Once you have checked the tank air valve, made certain the bladder was okay, and noted the low pressure where the pump turns on, you are ready to pressurize the bladder. Turn off the well pump and open a faucet at the lowest point in the house. Allow the water to run until it stops coming out of the faucet, leave the faucet on. Once the water stops coming out of the faucet use the air gauge to take a pressure reading at the air valve on the top of the tank. The air pressure should read 2-psi less than the pressure at which the pump turns on. If the pressure is low attach the air pump to the air valve on the top of the tank and pump air into the tank until the pressure reaches the correct pre-charge setting. Once that is done place the cap back on the air valve and turn the pump back on then close the faucet. If you cannot get the pressure in the bladder to increase and air starts coming out of the faucet the bladder has failed and you should follow the instructions in the paragraph above. If the air pre-charge is high when you check the pressure you should press the center pin and allow air to escape until the proper pre-charge pressure is reached then replace the cap on the air valve, turn on the pump and turn off the faucet.