The negative effects of hard water can be reversed through the use of softened water. A water softener works on the principal of “cation exchange,” in which ions of the hardness minerals are exchanged for sodium or potassium ions, effectively reducing the concentration of hardness minerals to insignificant levels. The exchange is accomplished in a tank, using a “resin” of tiny beads made from a special plastic material.
After a period of use, the sodium or potassium ions are completely exchanged and the unit has to be “backwashed” or “regenerated.” This requires the use of sodium or potassium chloride, which is loaded into a “brine tank” and dissolved to form a briny liquid used to recharge the system. There are two types of water softeners:
- Automatic
An automatic water softener is equipped with a timer, which starts the regeneration process at preset intervals. This usually occurs when water use is minimal, such as the early morning hours. - Demand Initiated Regeneration (DIR)
Instead of regenerating at a preset interval, DIR units use sensors or meters to regenerate when soft water runs out. Because they adjust to the amount of water actually used, DIR units consume up to 50 % less salt and water than preset automatic softeners.