WEBVTT - How Water Softener Works

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<v Speaker 1>Welcome to brain Stuff from how stuff works dot com

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<v Speaker 1>where smart Happens. Hi, I'm Marshall Brain with today's question,

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<v Speaker 1>how does a water softener work? We call water hard

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<v Speaker 1>if it contains a lot of calcium or magnesium dissolved

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<v Speaker 1>in it. Hard water causes two problems. First, it can

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<v Speaker 1>cause scale to form inside of pipes and water heaters

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<v Speaker 1>and tea kettles. The calcium magnesium participate out of the

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<v Speaker 1>water and stick to things. Eventually pipes can become completely clogged. Second,

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<v Speaker 1>the calcium and magnesium react with soap to form a

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<v Speaker 1>sticky scum and also reduces the soaps ability to lather.

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<v Speaker 1>Since most of us like to wash with soap, hard

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<v Speaker 1>water makes a bath or a shower less productive. The

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<v Speaker 1>solution to hard water is either to filter the water

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<v Speaker 1>by distillation or reverse osmosis to remove the calcium and

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<v Speaker 1>magnesium altogether, or to use a water softener. Filtration would

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<v Speaker 1>be expensive to use or all the water in a house,

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<v Speaker 1>so a water softener is usually the less expensive solution.

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<v Speaker 1>The idea behind a water softener is simple. The calcium

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<v Speaker 1>and magnesium ions in the water are replaced with sodium ions.

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<v Speaker 1>Since sodium does not precipitate out in pipes or react

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<v Speaker 1>badly with soap. Both the problems of hard water are

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<v Speaker 1>completely eliminated. To do the ion replacement, the water in

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<v Speaker 1>the house runs through a bed of small plastic beads

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<v Speaker 1>or through a chemical matrix called zeolite. The beads or

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<v Speaker 1>zeolite are covered with sodium ions. As the water flows

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<v Speaker 1>past the sodium ions, they swap places with the calcium

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<v Speaker 1>and magnesium ions. Eventually the beads or zeolite contain nothing

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<v Speaker 1>but calcium and magnesium and no sodium, and at this

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<v Speaker 1>point they stop softening the water. It's then time to

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<v Speaker 1>regenerate the beads or zeolite. Regeneration involves soaking the beads

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<v Speaker 1>or zeolite in a stream of sodium ions. Salt is

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<v Speaker 1>sodium chloride, so the water softener mixes up a very

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<v Speaker 1>strong Brian solution and flushes it through the zolder beads.

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<v Speaker 1>This is why you load up a water soften or

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<v Speaker 1>with salt crystals. The strong Brian displaces all the calcium

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<v Speaker 1>and magnesium that is built up on the beads and

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<v Speaker 1>replaces it again with sodium. The remaining Brian plus all

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<v Speaker 1>the calcium and magnesium is flushed out through a drain pipe.

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<v Speaker 1>Regeneration can create a lot of salty water, something like

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<v Speaker 1>twenty five gallons for each cycle. Do you have any

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<v Speaker 1>ideas or suggestions for this podcast? If so, please send

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<v Speaker 1>me an email at podcast at how stuff works dot com.

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<v Speaker 1>For more on this and thousands of other topics, go

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<v Speaker 1>to how stuff works dot com.