Hard water impacts households and not in a good way. The minerals that cause hardness can make clothes appear dingy and feel scratchy; leave spots on glassware and dishes; create buildup on showers, tubs, sinks, and toilets; and raise energy costs, soap, and detergent usage - among other concerns. [Note: Ad or content links featured on this page are not necessarily affiliated with WQA and should not be considered a recommendation or endorsement by WQA.]
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Hard water increases energy consumption of household appliances, according to research at New Mexico State University. The one-year study measured the energy usage of six gas and electric residential water heaters and found gas water heaters used 29% less energy and electric heaters used 21% less energy when operated on softened water. (See also sidebar, Battelle Memorial Institute: Softened Water Reduces Water Heating Costs by Up to 48 Percent.)
A Water Quality Research Foundation (WQRF) study - “Evaluation of Relative Effects of Hardness, Detergent Dose and Temperature to Evaluate Stain Removal Efficacy and/or Use of Less Laundry Detergent at Lower Water Temperatures” - found that softened water can reduce detergent use by as much as 50 percent and heating costs by up to 24 percent.
Determine if you have hard water by using WQA’s Diagnose Your Water tool.
What Makes It Hard, What to Do About It
Calcium and magnesium ions - present as salts such as sulfates and carbonates - cause water to be hard.
Consumers can reduce water hardness by buying or renting certified water softening systems and connecting them to their water lines.
How Softeners Work
Ion exchange - aka, cation exchange - water softening is the most common way for homeowners to soften their water.
In the ion exchange process, water passes through a bed of softening material, typically sulfonated polystyrene beads. Unwanted minerals in the water attach to the resin beads as sodium ions are released into the water.
When the resin beads become saturated with unwanted minerals, the softening system rinses the beads with dissolved salt, which scours the deposits from the beads and prepares the beads to remove more unwanted minerals. This rinsing and regeneration process occurs about once a week, usually at night.
Water softeners not only exchange hard ions for soft ions, they can remove most heavy metals, as well. However, to remove dirt, chemical and organic contaminants, a water filtration system containing different resin should be installed.
Two Ways Water Softeners Regenerate
There are two ways in which water softeners trigger regeneration cycles: 1) using a preset time clock, and 2) based on actual demand or usage. Time-clock-driven regeneration sometimes leaves the user with hard water when more water is used prior to regeneration than it is set for. The time-clock softeners can also waste salt when less water is used prior to regeneration. Demand initiated regeneration softeners are the most efficient technology because regeneration occurs only as needed based on the amount of water actually used.
Water Softener Selection
The non-profit Water Quality Association (WQA) can help homeowners select a quality water softening system that works best for their situation and budget. WQA’s Gold Seal Certification for water softeners is awarded to products that pass stringent laboratory tests, literature review and materials assessments, and have been submitted to periodic audits as required by the American National Standards Institute (ANSI) and the Standards Council of Canada (SCC).
WQA can also help consumers find water quality professionals in their area who can sell, install and service a unit.
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