Fleck 3900 3″ Water Softener, Timer Control Valve

Fleck 3900 Specifications When ordering a Fleck Control Valve, it is necessary for us to know the Height and Diameter of the tank the valve will be installed on. We will set the Fleck valve up to operate properly based on the size of the tank YOU specify for Tank Diameter and Tank Height. Please measure your tank while it is setting upright from the floor to the top of the tank, not including the valve, if present. Next, measure the diameter of the tank, near the top widest portion. If your height or diameter measurement is not found in the drop down selections, simply pick the next larger size.