Water Softener System Features

• A water softener is a home plumbing appliance for removing dissolved calcium and magnesium carbonates from your tap water through ion exchange. Water with lots of dissolved minerals is called "hard" water, says the PopularMechanica.com website. Hard water interferes with cleaning action of bath soap and laundry detergents and can damage plumbing systems. Water softeners feature three essential components: a mineral tank, a brine tank and a valve assembly controlled by a command module.

Mineral Tank

• The mineral tank is the water softener component where the dissolved minerals are removed from water. The tank is filled with plastic resin beads, carrying a strong negative charge, that are covered in sodium ions that carry a weak positive charge. Dissolved calcium and magnesium mineral ions carry strong positive charges. In use, the dissolved mineral ions cling tightly to the resin beads, displacing the sodium ions into the water. This turns the water into a weak salt water solution, giving it the distinctive "soft" feel.

Brine Tank

• Eventually the resin beads in the mineral tank become saturated and can't hold any more calcium or magnesium ions. The unit must be regenerated by flushing it with salt water from the brine tank, says PopularMechanics.com. First, a backwash reverses water flow in the mineral tank to flush out dirt. Next, salt water is drawn from the brine tank and flushed through the mineral tank. The sheer volume of sodium ions knocks the calcium and magnesium ions off the resin beads into the flush water, where they are carried away down the drain. The mineral tank is then flushed with clear water to carry away excess sodium, and the brine tank refills. Softened water is slightly salty, but most people don't notice the taste.

Valve and Controller

• The sequential actions of water softener regeneration are carried out through a mechanical multi-position valve driven by an electric motor controlled by an electromechanical or computer device. The simplest control device is a timer that regenerates the system at a preset time of day, said PopularMechanics.com. More sophisticated controllers monitor water use and initiate recharging only when a certain quantity of water has passed through the mineral tank.