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PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR
CHEMICAL CONTAMINANTS in WATER
CLOGGED SUPPLY PIPING
DEBRIS in WATER SUPPLY, Water Heater
DRINKING WATER TESTING
EPA GUIDE to WATER QUALITY
FHA WATER TESTS REQUIRED
FREEZE-PROOF A BUILDING
HARD WATER - SOFTENERS
HEAT TAPE USAGE GUIDE
MUNICIPAL WATER PRESSURE IMPROVEMENTS
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER
PLUMBING SYSTEM ODORS
PRESSURE CONTROL SWITCH ADJUSTMENT
REVERSE OSMOSIS CONCENTRATE DISPOSAL
SEWER GAS ODORS
WATER HEATER SCALE REMOVAL
WATER HEATER SCALE PREVENTION
WATER ODORS, CAUSE CURE
WATER PRESSURE & FLOW MEASUREMENT
WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER SOFTENERS & CONDITIONERS
WATER SOURCE ALTERNATIVES
WATER SUPPLY & DRAIN PIPING
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WINTERIZE A BUILDING
Water softener operation: here we explain how water softeners and similar water conditioners work, types of water softeners, and the basics of what water softener controls are present and what they do. How water softeners work, methods to remove minerals from home water supply.
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Also see SOFTENER ADJUSTMENT & CONTROLS where we provide details about water softener setting and salt dose adjustments.
Conventional ion-exchange water softeners used to remove minerals from "hard" water in buildings usually use salt in an ion-exchange process, swapping in sodium ions (salt) and causing calcium and magnesium to precipitate out of the building water supply (and to collect in the water softener).
Definition of "hard water": Hard water is generally taken to mean water containing minerals over 121 mc (micrograms) per liter of water, or over 7 grains of hardness per gallon.
Salt in the brine tank (red arrow in our photo at left) is used to place a charge of salt molecules in the resin tank (green arrow). During a regen cycle (explained below) under control of a timer or on some systems more advanced systems that actually monitor the mineral level in the water supply.
Resin inside the water softener treatment tank (green arrow in our photo) contains salt molecules which are brought into contact with building water as it passes through the softener. The "resin" is made of tiny plastic beads of zeolite which are coated with salt or potassium ions. (Ions are molecules that have an electrical charge.)
As hard water which is to be treated flows through the resin or treatment tank (tan arrow in our photo at left) containing the salt-coated zeolite resin beads, salt molecules (NaCl) on the bead surface are "swapped" into the water displacing other mineral molecules that we're trying to remove from the water, such as Calcium (Ca or CaCO3) or Magnesium (Mg) that clog up pipes and create other problems. The Ca or Mg ions stick to the resin beads where they have replaced the NaCL. The resulting "conditioned water" or "soft water" (blue arrow in our photo at above left) flows out of the treatment tank and into the building for use.
In sum, during that contact time as your building water passes through salty resin inside the treatment tank, the ion-exchange occurs to soften the water.
Periodically the water softener needs to recharge itself, a step which is controlled either manually by the
homeowner or run automatically by a timer built into the water softener. Usually these steps involve pumping water backwards through the water softener and to a building drain, followed by
dissolving salt tablets or crystals in a nearby holding tank and pumping the new salty water into the softener.
The salty water passing back through the treatment tank has given up some of its salt to regenerate the resin beads there and it has picked up the un-wanted calcium and magnesium that were previously removed from the building water as it passed through the same tank earlier. The water used during the regeneration cycle gallons is discharged through a drain tube into an approved destination like a drywell.
How often a water softener needs to backwash and recharge itself depends on two factors: how much water is used in the building and how hard the water is.
How much salt a water softener uses at its backwash cycle depends on the hardness of the water being processed.
Water softeners address these two variables and is regenerated or "recharged" by these means
The water softener installer sets up the water softener control to specify
Some experts suspect that many homeowners use more salt and more frequent backwashing than the water usage and hardness require.
Details about how to set or adjust the water softener controls are at SOFTENER ADJUSTMENT & CONTROLS.
Details about how a water softener is installed and hooked-up are at INSTALLATION of WATER CONDITIONERS
Frequently Asked Questions (FAQs) About How Water Softeners Work
Question: Aqua Cera Water Softeners?
Curious if you're familiar with the brand of water "conditioner" Aqua Cera. Salt and electric free unit that uses it's media to condition, not soften, water. Water will still test hard as usual however their claim is that there will no longer be any scale build up at fixtures. They also recommend these units for people who don't like the slimy feel of softened water. Sounds fine and good but how proven is this technology? - Anon 6/14/12
Anon, we discuss these, to put it nicely, highly questionable tools, gadgets, and magic equipment in more detail at OTHER SOFTENER METHODS. Generally, there is no independent, credible evidence whatsoever that the systems you describe actually work, and the "white papers" and other literature we've found has been prepared by the vendors themselves or their agents. If it's too good to be true, it is probably not true.
Question: Should water actually leave the water softener during a backwash cycle?
Never used a water softener before, went to do a backwash and regenerate. Should the water actually leave the softener and then refill because it sounds as though it wants to run but no water is leaving the tank and filling back up - Jhar1986 9/19/2012
Reply: yes. Here are the details:
Jhar, reviewing from above,
Questions & answers or comments about types of water softeners, what controls are found on water softeners, & how water conditioners and water softeners actually work.
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Technical Reviewers & References
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