3. a, b, and c. All three factors are critical to efficient water softener operation. Generally, softeners are operated at the most economical rates with a) three to eight pound salt levels, b) about 10 percent sodium or potassium chloride in the regenerant as it moves through the ion exchange resin beads, and c) a brining flow rate between 0.25 and 0.40 gallons per minute per cubic foot of resin.
4. False. The dissolving process also tends to pack the salt particles together tighter.
10. False. DIR softeners are likely to use about 25 percent to 50 percent less salt than time clock units.