Pressure Tank Precharge

Pressure Tank Precharge Inside your pressure tank is a big rubber balloon. It is filled, at the factory, with pressurized air from a valve on the tank that looks like a valve on your car's tire. It is pressurized at a HIGHER pressure than you need. Check it with a tire pressure gauge. With this high setting, the water cannot compress the air balloon, so the tank is not yet effective. Once you have set your pressure switch as described above, you need to let some air out of the tank. To do this, turn off the power to your pump. Open a water outlet to relieve the pressure in the tank, then close it again. Now let air out of the tank until the tire gauge indicates 2 or 3 PSI LOWER than your cut in pressure. This is also described on instructions that come with your pressure tank. If you have more than one pressure tank, adjust them equally. Turn your pump on, and measure how long it takes to charge the tank to cut-off. As soon as the pump starts, the pressure should quickly rise to the pre-charge pressure. Then it will rise very slowly as it compresses the air in the tank. Fix yourself a sandwich or something. When it finally reaches cut-out pressure and shuts off, note how long it took, and write down "cycle time." on the wall near the tank. Also record your cut-in and cut-out pressure settings. If you have an ammeter measure the current (Amperes) that your pump draws at the beginning and at the end of the pumping cycle. If you have trouble in the future, changes in these readings will indicate where the problem lies.