Water Pressure Tank Air Valve

On composite tanks the valve can be found toward the base of the tank.

Water pressure tank air valve.

Unscrew the plastic cover from the air valve on the top of the tank. Water tank pressure measured at the air gauge or schrader valve on the tank top will creep up to above normal levels. Check the pressure tank s air valve. Captive air water tanks that use an internal bladder to keep water and air separate such as the well x trol water pressure tank will display an air valve usually on top of the water tank and often red in color such as shown in this photograph.

Check the air pressure in the water tank by using an accurate air pressure gauge such as a dial type or digital tire pressure gauge to measure the air pressure at the schrader valve on the water tank. The internal water tank air valve stem part valve stem core that is replaced can be purchased with different spring strengths for different pressure ranges but in fact given that the pressure range of a typical water tank is 20 70 psi like a car tire almost any common tire valve stem core would work fine as a replacement if your valve stem won t stop leaking. The air will trigger the piston inside the gauge and measure the air pressure within the tank. Near the tank top on the tank side on a tee at the bottom of the water tank or on well piping nearby.

Choose from a valve for air inert gas water hydraulic oil fuel oil gasoline or diesel fuel and a set pressure from 150 to 3 300 psi. At left is an air inlet valve located on the tank tee near the bottom of what was a bladderless water pressure tank. Pressure relief valves for water these valves are commonly used with pumps in low pressure water systems. A new tank costs about 200 and up.

The air inlet valve on a bladderless water pressure tank may be at any of several locations. Bleeding air out from the tank top will prove a short remedy and pressure will creep up again. Use a small screwdriver to depress the air valve to see if water comes out. Adjust the pressure with an air compressor if necessary.

A common cause is a failed check valve. If the valve fails water streams back down the well and the pressure switch turns the pump on again. Unscrew the cap covering the valve and press the tire gauge down on the valve. Replacement is your only option.

The tank pressure should be within 10 of the original factory water tank pressure setting. The check valve or foot valve prevents the well pressure tank from sending water back down into the well after it has built up with water pressure.