How do water softeners work

A.� They all work along the same basic principle, replacing unwanted minerals in the water with more acceptable ones: the process is called ion exchange.

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Generally calcium and magnesium ions are replaced with sodium ions.

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The softening unit contains a porous resin covered with negatively charged molecules that attract and bind positive ions. To start with, positively charged sodium ions coat the resin, but, because their positive charge is weaker than those of calcium and magnesium, they are released by the calcium and magnesium ions as water flows over the unit. So the unwanted calcium and magnesium minerals are replaced by sodium.

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Q.� Doesn't the resin become 'full' of calcium and magnesium

A.� Yes, and it has to be 'renewed' every few days. The unit rinses the resin with sodium chloride, or saltwater to you and me.

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The high concentration of sodium ions in the salty water displaces the calcium and magnesium ions on the resin, and they’re rinsed away as waste. The end result is a softening unit once again covered in sodium ions waiting to attract the unwanted calcium and magnesium.

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Q.� Why do we soften water

A.� Because household detergents work more efficiently with soft, rather than hard water. Calcium and magnesium ions interfere with the action of household soaps and detergents, but sodium doesn't. The calcium and magnesium minerals combine with the soap and stop it from foaming properly.

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Click here to read how soap works and why it needs to foam.

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Another efficiency reason for softening water is that calcium and magnesium deposits can build up in your plumbing system, reducing the flow of water to taps. A build up of these minerals in water heaters creates a scale that interferes with their efficiency.

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Q.� So it isn't healthier to soften water

A.� No, hard water poses no health hazard.

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Q.� Where do the chemicals come from, I thought water just contained hydrogen wand oxygen

A.� Yes, but most of the water we use has passed through the ground before it makes it into our taps, picking up unwanted minerals as it does.

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Q.� Is all the household water softened

A.� No just our washing and drinking water.

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Want to know how something works Click here to ask.

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by Lisa Cardy