Item Purpose Construction Tank Water pressurized vessel that holds the resin in place Typically fiberglass Head Determines the frequency of backwash and controls the flow of water during service, backwash, brine cycle, brine refill and rinse cycle. Noryl or Brass Distributor and Riser Provides the return route to the head for the treated water Plastic with a slotted basket at the bottom Resin Provides sites for the exchange of ions Typically 10- 30 mesh Underbed Gravel Provides support for the media and a collection space for the treated water. #20 or greater flint gravel Brine Tank Stores the salt that is used to regenerate the media Plastic container with cover

To understand the operation of a water conditioner (softener), one must first understand the concept of ions. Many chemical elements form compounds that when dissolved in water separate and form electrically charged particles called ions. These ions are surrounded by water molecules. Because opposite charges attract each other, these ions move to and attach themselves to objects with charges opposite theirs. A common compound that demonstrates this property is NaCl (Sodium Chloride or common table salt). The ions that are formed in water from this compound are Na+ and Cl-. The small +/- signs indicate these elements have formed ions and that their charges are either positive(+) or negative(-). Their are many elements that form ions when dissolved in water that have undesirable characteristics. Some common ones are:

Ion Characteristics Ca++(calcium), Mg++(magnesium) Gives water the characteristics we call hard. It causes - damage to heating appliances and fixtures because of scaling, excessive soap usage, dry skin and premature deterioration of fabrics washed in water containing it. Fe++ (iron) When exposed to air turns red/orange and cause staining Mn++(manganese) When exposed to air turns black and causes staining

Operation The water conditioner consists of two tanks- a resin tank and a brine (salt) tank. The resin tank is filled with a resin that consists of small plastic beads. This resin is called cation ("cat" "ion") resin. The beads have a permanent charge. The charge causes the beads to attract positively charged ions. The resin is placed into service with Na+ ions on the beads. When the hardness ions (Ca++ and Mg++) come in contact with the Na+, they remove the Na+ and take the Na+'s place on the beads. The Na+ is now dissolved in the water (see figure above). This sodium leaves the resin tank and is delivered to the tap with the water (see sodium and softening). When most of the Na+ is removed from the resin beads the softener head starts the regeneration process. It sets the control to allow raw water to go to the house during regeneration. This is done so none of the salt used during regeneration can enter the house plumbing. The resin is then regenerated by drawing in a high concentration salt (NaCl) solution from the brine tank. This salt solution is washed over the depleted resin. The salt solution contains Na+ and Cl- ions. The Na+ is placed back onto the beads and the Ca++, Mg++ and Cl- are washed down the drain. The media is then rinsed with fresh water to remove all the remaining salt. More water is added to the brine tank to dissolve salt for the next regeneration. The head then sets the control to service and there is treated water again available at the house.

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