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How a water softener works

Hard water

Water hardness, or hard water, refers to the amount of calcium and magnesium contained in water. This is a natural result of water as it moves through the water cycle. These minerals are not harmful when consumed through your drinking water, but can cause issues throughout your home.

Water with high levels of calcium and magnesium can clog pipes with mineral build-up left behind as the water flows through.

Hard water also reduces the ability of soap to lather, and the minerals form a sticky scum that prevents easy rinsing of anything being washed. This includes your hair, dishes, and glasses with water spots. They will all have a white chalky scale or residue left behind.

Water softeners

A water softener does not produce pure water, but it removes the calcium and magnesium in hard water by using resin beads in the “ion exchange process” and cleans itself periodically by the process of “regeneration”. Water softener systems are made up of a Media Tank, Brine Tank, and Control Valve. Smaller capacity models combine the media tank and brine tanks into one cabinet.

The Media Tank is where the water is treated and hard water is softened (calcium and magnesium are removed).

The Brine Tank is where a highly concentrated solution of salt is stored, or potassium may be used as a salt-free alternative, albeit more expensively.

The Control Valve is the device that regulates the flow of water into and out of the media and brine tanks during regeneration.

Ion exchange

As incoming hard water passes through the media tank, the resin beads attract the hard water minerals and they are removed, producing soft water. This is the normal operating mode of your water softener, as it softens hard water entering your home, giving you soft water and all its benefits.

Read more about the benefits of soft water

During ion exchange, the control valve keeps track of the amount of water used and determines when the media needs to be cleaned (regenerated).

Regeneration

To clean the resin beads, now coated with the calcium and magnesium removed from your water, the softener uses the process of regeneration which consists of three cycles: Backwash, Recharge, and Rinse/Refill.

Regeneration begins in the Backwash cycle, where the valve reverses water flow in the tank in order to flush out the tank of excess water and debris.

In the Recharge cycle, the brine solution is pumped into the mineral tank. This concentrated solution forces the calcium and magnesium off of the media, cleaning it of hardness.

The excess calcium and magnesium is then flushed out of the tank and down the drain in the Rinse cycle and the brine tank is refilled with treated, soft water ready for the next regeneration cycle to begin.