Water Softeners

Using Water Softeners: Rochester MN


water softeners rochester mn


How Do Water Softeners Work?


Chemistry: A Review

Softening water is a chemical process, because the goal is to remove minerals from the water. In chemistry, these minerals are more accurately called ions, which are elements that have a positive or negative charge. When you put table salt on your food, you are using sodium chloride salt (NaCl). The sodium and chloride are both separate, CHARGED (+ or -), ions Na+ and Cl-, which combine to form the NaCl salt, which is uncharged or “neutral”. In water, H2O enters the scene and breaks up (dissolves) NaCl like two people in a bar fight, they each go back to their charged forms: Na+ and Cl-.


Why do we need water softeners?

Water softening systems work two remove two specific ions from “hard” water: calcium and magnesium. Water softeners then replace these ions with sodium ions. Justifying the demand for soft water is easy. Calcium and magnesium ions interfere with soaps and detergents, they lead to scale and grime build-up, staining, discolored clothing, and irritated skin. Replacing these ions with sodium helps soap and detergents work more effectively, allowing you to use less.


The water softener is located such that it softens water used for indoor household use, like drinking and washing. There are several cubic feet of porous plastic resin covered with molecules that attract and bind positive ions (like magnesium and calcium) dissolved in the water. Yes, sodium Na+ ions normally coat the resin (positively charged ion). But as water flows over the resin, the magnesium and calcium displace the sodium ions because their positive charge is greater by one each (Mg2+ and Ca2+), a significant difference. This displacement occurs to maintain the electrical charge balance at the resin’s surface. Gradually, most of the sodium ions are released into household water, saturating the resin with calcium and magnesium ions. There is a function built into the water softener that renews the resin by rinsing it with a concentrated sodium chloride (NaCl) solution, usually at night. Due to the high concentration of sodium, magnesium and calcium ions are displaced from the resin, restoring it back to its sodium-saturated state. The unwanted magnesium and calcium ions are then flushed, allowing the system to resume normal operation. Periodically, a new bag of sodium chloride must be added to the softener unit.


Next are the numbers. Each one cubic foot can remove calcium and magnesium from approximately 3200 gallons of hard water (defined by the Water Quality Association as 10 grains per gallon hardness). Overall, 750 milligrams of sodium ions are added to each gallon of water. The FDA considers this amount to be in the “low sodium” range for commercial beverages. If you are in the select group of people that this amount of sodium can have significant health effects, you can install potassium-based resins. Though the drawback is expense, as potassium chloride salt is more expensive than sodium chloride salt, and is necessary to replenish the resin.

If you have questions regarding your water softener, or desire a new one, please reach out to Plumbers Rochester MN to get the help you need, today.