Water softening how does it work

Find out more about regeneration here. A water softener simply has two jobs — to soften water and regenerate itself. Single cylinder water softeners need to pause the water softening process to regenerate, our innovative twin-cylinder design means that the regeneration process can take place at any time without interrupting your enjoyment of softened water. All you need to do is simply top the block salt up when it runs out, this is the only maintenance needed.

Operation is silent during normal use and regeneration sounds similar to the filling cycle on a washing machine, lasting around 10 minutes. Find out more about maintenance here. Softened water provides so many benefits to your home and family, from a shiny kitchen and bathroom to being soft on skin and hair. Call Get a 3 month trial. How a water softener works. Calcium and magnesium in water both carry positive charges.

This means that these minerals will cling to the beads as the hard water passes through the mineral tank. Sodium ions also have positive charges, albeit not as strong as the charge on the calcium and magnesium. When a very strong brine solution is flushed through a tank that has beads already saturated with calcium and magnesium, the sheer volume of the sodium ions is enough to drive the calcium and magnesium ions off the beads.

Water softeners have a separate brine tank that uses common salt to create this brine solution. In normal operation, hard water moves into the mineral tank and the calcium and magnesium ions move to the beads, replacing sodium ions. The sodium ions go into the water. Once the beads are saturated with calcium and magnesium, the unit enters a 3-phase regenerating cycle. First, the backwash phase reverses water flow to flush dirt out of the tank.

In the recharge phase, the concentrated sodium-rich salt solution is carried from the brine tank through the mineral tank. The sodium collects on the beads, replacing the calcium and magnesium, which go down the drain.

Once this phase is over, the mineral tank is flushed of excess brine and the brine tank is refilled. Most popular water softeners have an automatic regenerating system. The most basic type has an electric timer that flushes and recharges the system on a regular schedule.

During recharging, soft water is not available. A second type of control uses a computer that watches how much water is used. When enough water has passed through the mineral tank to have depleted the beads of sodium, the computer triggers regeneration. These softeners often have reserve resin capacity, so that some soft water will be available during recharging. A third type of control uses a mechanical water meter to measure water usage and initiate recharging.

The advantage of this system is that no electrical components are required and the mineral tank is only recharged when necessary. When it is equipped with two mineral tanks, softened water is always available, even when the unit is recharging. Companies that sell water softening equipment generally offer test kits that help you determine the hardness of your water. For commercial testing sources, check your Yellow Pages under "water analysis.

The salty rinse water, calcium and magnesium ions are flushed down the drain, and the system resumes normal operation. Every so often it is necessary to add a bag of sodium chloride salt to the softener unit to prepare this salty rinse water.

Each cubic foot of resin can effectively remove calcium and magnesium from about 3, gallons of hard water, which the Water Quality Association defines as 10 grains per gallon hardness. The process adds about milligrams of sodium to each gallon of water, which the U. Food and Drug Administration considers to be in the "low sodium" range for commercially sold beverages.

For people who are concerned about their overall intake of sodium, resins that instead release potassium into the water do exist, but the potassium chloride salt used to renew the resin every few days is more expensive than ordinary sodium chloride salt. Sign up for our email newsletter. Already a subscriber? Sign in.

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