-a series of SIX VIDEOS about safe and effective water systems.
Tape #1
Hard Water
MRC Catalog #75702
This VIEWER REFERENCE GUIDEis yours to keep!
DO NOT RETURN ITwhen you return the tape.
What are the signs of hard water?
water containing lots of calcium and magnesium
roughened, hard-to-clean, unsightly surfaces (scale) in bath
tub, shower, coffee pot, tea kettle;
increased cost of heating hot water (scale build-up in the water heater);
reduced water flow from faucets (scale build-up in water pipes).
* Scale build-up may shorten the useful life of water using appliances, water heaters, and plumbing.
How do water softeners work?
-Most home water softeners use the ion-exchange process.
Ion exchange softeners are filled with tiny beads of ion exchange resin which contains sodium-a mineral that does NOT cause water hardness.
When hard water passes through the resin, calcium and magnesium ions (the hardness-causing minerals) are absorbed
by the ion-exchange resin, and sodium ions are released.
When the sodium in the resin is depleted, no further hardness can be absorbed. The softener is then "exhausted," and needs
to be "regenerated."
Salt brine (which contains lots of sodium) is used to regenerate the softener. The brine removes the calcium and magnesium
which the resin has absorbed, and replaces it with sodium so that more water can be softened.
If most softeners operate on the same principle, why do some cost $400 - $500, while others $1,000 or more?
-There are several possible reasons, but a key one is the way in which regeneration is controlled.
THERE ARE THREE COMMON REGENERATION CONTROL SYSTEMS.
Time-clock control
You program the clock to regenerate on a fixed schedule (every
day, every fifth day, etc.) depending on your needs for softened water.
NOTE-Fixed regeneration scheduling may occasionally waste water and salt by unnecesary regeneration- when you're away
from home on vacation, for example.
Water meter control
Regenerates after a fixed amount of water has passed through the softener.
NOTE-This reduces unnecessary regeneration, but may not totally eliminate it. This kind of unit is often more expensive than time-clock control units.
Hardness sensor control
Sensor detects hardness of the water leaving the unit, and
signals softener when regeneration is needed.
NOTE-This minimizes potential for unnecessary regeneration. This kind of unit is usually the most expensive type of softener.
Recommended steps in selecting a home water softener-
Test untreated water for hardness and iron content.
Discuss softener sizing with suppliers
Ask about hardness removal capacity-the number of grains of
hardness that can be removed between regenerations. Softeners with small capacities must regenerate more often.
Your daily softening needs depend on:
A. the number of persons in your household;
B. the hardness of your water.
Use water meter readings to determine average water use, or estimate 50 to 75 gallons per person per day.
To determine daily hardness removal, multiply daily household water use (measured in gallons) by the hardness of the water
(measured in grains per gallon) Example: 200 gallons per day x 15 grains per gallon = 3000 grains of hardness removed daily.
Ask about rated service flow-the number of gallons per minute the unit can soften.
NOTE-Needs will vary with the number of water-using fixtures in the household and the number of persons using them.
Ask about iron limitations.
Does the iron level in your water exceed the maximum iron removal capacity (recommended by the manufacturer) of the unit you are considering?
If so, iron may foul the softener, eventually causing it to become plugged. In this case, your equipment dealer may
recommend installation of an iron filter ahead of the softener to prevent iron fouling.
SOME COMMONLY-ASKED QUESTIONS ABOUT SOFTENERS:
My softener worked great when it was first installed, but it doesn't seem to soften like it used to. Why?
Iron fouling is the most common cause of deteriorating softener performance. Putting a resin cleaner in with the salt sodium
remove accumulated iron during regeneration. You may need to do this several times. In severe cases you may need to have the resin removed and cleaned by professionals.
How much sodium is added to my diet by drinking water treated with an ion exchange softener?
The amount of sodium added to your daily diet is roughly equal to the hardness of your water, measured in milligrams per liter.
For example, if your water hardness is 400 milligrams per liter, then softening will add about 400 milligrams of sodium to your daily diet.
-other sources of information-
Your local county or community environmental/health sanitarian
Iowa Department of Public Health, Lucas State Office Building, Des Moines, IA 50319-0075 (515-242-6340)
University of lowa Hygienic Laboratory Oakdale Hall, lowa City, A 52242 (319-335-4500)
Geological Survey Bureau. Iowa Department of Natural Resources, 123 North Capitols lowa City. IA 52242 (319-335-1575)
National Sanitation Foundation. 3475 Plymouth Rd., P.O. Box 1468 Ann Arbor, Ml 48106 (31 3-769-8010)
Water Quality Association, 4151 Naperville Rd., Lisle IL 60532 (708-505-0160)
This material is based upon work supported by the U.S. Department of Agriculture,
Extension Service. under project number 89-EWQI-1-9108
Ames, lowa 50011
AE 3058 July 1991
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