A water softener is a water filtration system that treats hard water and converts it to soft water. It works by using the ion exchange process in which a certain amount of sodium ions is exchanged for calcium and magnesium ions. Water softeners work by removing these hard water minerals.

Water softeners are highly sought after in areas plagued with extreme water hardness due to a high concentration of hardness minerals such as calcium and magnesium in the water underground. Soft water, the end product of the water softener, has more benefits to the household and is more friendly to the surfaces, pipes, and appliances in the home. The beauty of the water softeners is that you can test their potency by conducting a hardness test that examines hard water in grains per gallon (GPG).

Before we talk about how a water softener works, we need to understand the importance of having soft water in our households.

Why You Need a Water Softener

To Protect your Pipes and Appliances from the After-effects of Calcium and Magnesium Ions

Hard water poses no threat to your health because calcium and magnesium are good for the body. However, that’s not the case for non-living things such as your water heaters, laundry machines, and your pipes. Hard water usage gradually leads to an accumulation of scales in your pipes and appliances that can damage them. It does the most damage to your water heater because the more it heats water, the more calcium and magnesium hardens and gets stuck on the heating elements.

These scales ruin your pipes and making them prematurely eligible for a replacement by clogging them. This automatically lessens the water supply to your home and affects surfaces such as your sink and faucet heads over time. That’s why water softeners are important.

Hard Water Causes Dry Skin and Hair

No one wants to have flaky, itchy, and dry skin after having their bath. But that’s exactly what will happen if you use hard water to bath. Hard water contains a high concentration of hard minerals that stays on your skin and your hair.

Ironically, they give you the impression of having a good bath because you will feel very clean. However, as soon as the water dries, your skin feels dry and itchy. The same thing goes for your hair. They make your skin gradually lose its shine and strength. If you’re keen on appearance and skincare, this is a good reason to get a water softener.

To Prevent a Botched Laundry and Dishwashing Activity

You tend to use far more soap or detergent with hard water than you do with soft water. This is because hard water hardly absorbs soap or lathers. Aside from the low soap efficiency of hard water, your dishes and entire kitchenware (washed with hard water) will be spotted.

Then for your clothes, they’ll fade fast. Clothes quickly lose their color when washed with hard water because it’s harsh on fabrics. Even worse, your clothes will become coarse and less comfortable on your skin when you wear them. This point emphasizes the need for water softeners.

Softened Water Saves you Money and is More Efficient in the Home

Softened water being supplied to the home prevents the development of scales, which won’t affect the ability of the pipe to channel water to the house. Plus, you spend less on repairs. There’ll be no premature repairs or replacements for both appliances and pipes. Scales greatly reduce the lifespan of your pipes and appliances. Hence, we need to prevent their presence to ensure your appliances and pipes last as long as they’re supposed to.

It Creates a Balance in the Distribution of Minerals in the Water

Water softeners remove calcium and magnesium from the water and release sodium or potassium chloride in their place. This greatly lessens the presence of calcium and magnesium ions in the water and keeps their presence in the water minimal. The presence of sodium in the soft water strikes a balance in the mineral content of the water. Such water is fit for consumption, cooking, and cleaning and poses no health challenge. Sodium is known for regulating bodily fluids and transmitting neural impulses. Aside from calcium and magnesium, the water softener also removes iron and manganese from the water.

Now that you know the reasons to purchase a water softener let’s get you familiar with the demerits of a water softener.

Disadvantages of a Water Softener

The Presence of Salt in Water

There’s always the issue of too much sodium in softened water. People who usually drink tap water are against the use of water softeners because these systems increase their daily intake of sodium ions. Depending on the frequency of hydrating one’s body, it’s very likely to go beyond the recommended quantity of sodium per day. Not that the consumption of these amounts of sodium will cause severe health issues, but it calls for concern.

Softened Water can’t be Used to Irrigate Farms

Water that’s low or deficient in calcium and magnesium ions but has healthy levels of sodium chloride can’t be used to irrigate farms. Softened water triggers the development of soils with an alkaline pH. Such soils are usually poorly structured and cannot make an irrigated farm productive.

The Installation and Maintenance of the System is Costly

You can spend as high as $2,000 to install a water softening system in your home. Aside from the cost of the purchase, the installation costs, there’s the issue of maintenance. The resin beads and the sediment filter will need to be replaced at some point. Also, the brine tank of the water softener will need to be topped up from time to time as the quantity of sodium or brine solution lessens. Once the brine solution is depleted in the brine tank, the water softening abilities of the water softener system will wane. This is because the resin bead has no sodium left to exchange for calcium and magnesium.

The Substitute for Salt in Water Softening is Also Costly

Potassium chloride is a worthy substitute for salt in the water softening process. However, they are not cheap. In fact, they’re more costly to acquire than sodium ions. While a bag of salt will cost you a maximum price of $6, you can spend up to $30 on potassium.

The System is Wasteful

The water softener system usually wastes a lot of water during the regeneration of the media beads. This periodic process involves a lot of salt and water, which is used to backwash the system. The resultant effect is a lot of wastewater which is bad for the environment. This also means an increase in water usage by the home and a higher water bill.

The Major Components of a Water Softener

The water softener comprises three major parts: the mineral/resin tank, brine tank, and control valve. They’re all vital parts of removing calcium and magnesium ions from the water, overseeing the water flow, and the periodic but essential regeneration process.

Mineral/Resin Tank

This part of the water softener is where hard water comes out as softened water. First, the resin tank receives hard water, which comes through the resin beads or bed. In the process, the resin beads attract calcium and magnesium to it and discharge a certain amount of sodium ions from the brine tank into the water. Then, the water flows into your house.

Brine Tank

This part of the water softener is also key in the softening process as well as regeneration. The brine tank is typically shorter than the resin tank, and it’s usually positioned adjacently to it. The brine tank contains a strong concentration of sodium ions or potassium to rejuvenate the positive charge of the resin beads.

This tank is periodically refilled with salt or potassium to keep the water softener in optimum condition. These minerals usually dissolve to the bottom of the water tank. A large quantity of brine solution is generally withdrawn from the brine tank when the control valve realizes the resin beads’ water softening abilities have declined. This brine solution is usually flushed via the resin beads in the resin tank. Once the brine tank no longer has salt, the water softening system will not soften hard water.

Control Valve

This part of the water softener is responsible for measuring the quantity of water that flows through the resin tank into your home. It usually has a meter that measures the water supply coming from the source to the media beads. After some time, the ability of the resin beads to soften hard water gradually declines. So the control valve triggers the regeneration process to flush out the accumulated minerals (calcium and magnesium) on the resin beads before they severely hamper the softening process.

The valve also has a programmed console with the capacity limit, when the control valve can automatically trigger the softener to commence the regeneration process. This limit depends on factors such as the size of the home and the degree of water hardness. Therefore, control valves are vital to the efficiency of the water softener.

How Does a Water Softener Work?

So, not that we know the main components of a water softener, let’s have a quick look at this video that explains how a regular water softener works:

Now let’s dive a little bit deeper into the details of the process:

The Ion Exchange Process (The Science and Depth of It)

The ion exchange process enables the water softeners to eliminate what hard water contains. The ion exchange involves the physical and chemical composition of the minerals (sodium, calcium, and magnesium) present in the water. Minerals are made of atoms. Now, these atoms are subdivided into two categories. The first category is referred to as cations, and they carry a positive charge. The second category of atoms is called ions, and they carry a negative charge. These two categories of atoms have a magnetic attraction to each other.

Ion exchange enables removing different ions (atoms with a negative charge) and substituting with other ions and even cations. The pull of these atoms has different intensities. For instance, calcium and magnesium have a very intense positive charge in contrast to others. Water softeners work by leveraging these atoms with a positive charge to get rid of hardness minerals such as calcium and magnesium, with resin beads inside the resin tank. After all, these hard water minerals are the very reasons water softeners are needed.

After a continual ion exchange process over some time, the water softener works out its maintenance by initiating regeneration once the resin beads have accumulated a specific volume of hard water minerals. These hard minerals are usually flushed or backwashed with salt or brine solution. While calcium, magnesium, sodium are classified as cations or positively charged minerals, the resin beads inside the water softeners carry a negative charge. Chemically named Sodium Chloride (NaCl), salt is a combination of negative (chloride) and positive (sodium) minerals. When salt goes through the resin beads during the regeneration process, the beads relinquish these agents of water hardness to draw sodium ions.

Now, a media must be present in the resin tank to treat hard water. The media is responsible for creating the ideal conditions for the ion exchange process to be effective. Aside from the resin beads we know, another media used is zeolite.

Like the resin beads, the zeolite also has a negative charge, which can draw or attract positively charged minerals. This media begins the ion exchange process by drawing the sodium ions to their surface. When hard water flows through the water softener tank, the media also draws the hard water minerals to it. These hard water minerals soon displace sodium ions on the surface of the beads because they possess a less intensive positive charge.

These hard water minerals remain stuck on the resin’s surface while softened water flows into your home. This water is free of the hard water minerals that trigger the development of scales in your pipes and appliances and consequent plumbing issues. It should be noted that water treated by the water softener isn’t salty. It just contains trace amounts of sodium ions.

The Regeneration Process

The water softener system uses this process to sanitize and rejuvenate itself to treat hard water for as long as possible continually. The system uses salt and water in this process.

In this process, hard water minerals (calcium and magnesium) accumulated on the resin bed through continual hard water supply are flushed out of the system. This is another crucial process to understanding how a water softener works. Without this process, the water softener will be ineffective because the media bed will be heavily laden with calcium and magnesium. It is a process that’s even more technical than the ion exchange process.

Regeneration Cycles

Counter-Current Regeneration

This is a type of regeneration cycle in which water flows through the base of the resin tank, which is typically the exit point. This cycle involves the upwards flow of the brine solution through the media bed. It begins from the bottom of the media (the area with the least presence of accumulated calcium and magnesium). By the time the brine solution gets to the top of the media (the surface area where the water softener system initiates contact with hard water), it is still high in concentration.

This regeneration cycle is usually more conservative than the co-current regeneration cycle because it uses much less salt and water. It also enables a more equitable distribution of the rejuvenating sodium. This way, the most intensely charged resin beads will be at the base of the resin tank, the point just before the water flows into the house. This regeneration cycle is also referred to as upflow brining.

Co-Current Regeneration

This cycle is referred to as downflow brining. It works inversely to the counter-current regeneration cycle. In this cycle, the brine solution flows into the mineral tank of the water softener through the normal entrance. This solution makes contact with the media beads from the top, and it involves another ion exchange process. Once the brine makes contact with the beads, the salt triggers the media beads to discharge the calcium and magnesium being held in exchange for sodium.

The contact between the brine and the media will trigger the hard water minerals to flow through the entire water softener. These minerals are in strong concentration due to the accumulation. The salt solution forces more hard water minerals through the media, and in the process, swapping and re-swapping of minerals occur. The concentration of the salt solution would have considerably weakened by the time as the hard water has flowed out of the water softener. In this cycle, the beads with the strongest charges are usually at the top of the media bed in the water softener. Therefore, it uses much more salt and water in its regeneration process.

What Influences or Prompts the Water Softener System to Regenerate?

This is another crucial thing to help you understand how a water softener works. What influences the water softener system to regenerate depends on the water softener’s capacity, model, and brand. The valve of the water softener usually controls regeneration. However, there is time-initiated regeneration and demand regeneration.

Time-Initiated Regeneration

This is when regeneration is typically set off by timing. The control valve usually has a clock that can be programmed to regenerate the water softener after a specific number of days and at a particular time (usually at midnight when the demands or water usage is lowest). For example, if you set the clock to regenerate every seven days, the water softener is placed on a weekly regeneration routine. The configuration of the valve’s clock should depend on the degree of water hardness in your environment, the level of water usage in the home, the size of your household, and finally, the capacity of your mineral tank. For any reason, if there is a need for water when the water softener is regenerating, you’ll have to settle for hard water, which can be accessed via an automated bypass function of the water softener.

Demand Regeneration

This is another way the water softener works. It works when the water softener regenerates after a certain amount of hard water has been treated through the water softener. You can also say the water softener regenerates after removing a certain amount of calcium and magnesium from the water supply to the home. This type depends solely on the level of water usage. The more hard water your water softener treats, the sooner the water softener will need to regenerate. The size of your household directly influences the level of water usage. The more occupants in your house, the more the water demand.

Issues in Regeneration

Several things can go wrong during the regeneration process of your water softener system. This is one more thing to note about how a water softener works.

Faulty tubing in your Brine Tank

The first thing is a faulty or leaking tube from your brine tank. Since salt is crucial to this process, this means that your system cannot flush out hard water minerals such as calcium and magnesium.

Inaccurate Valve Configuration

This is perhaps the most common issue pertaining to the regeneration process of the softener system. It’s either you miscalculated the time your softener should regenerate or the quantity of hard water it should soften before regenerating. Again, this is more common if you are not conversant with the factors that should determine your valve setting.

Faulty Valve or Timer

This should be fixed. Otherwise, regeneration in your water softener may have to be done manually, which may not be convenient. You’re even likely to forget, and when your water softener is overdue for regeneration, it can be a problem for its efficiency.

Salt Mushing

This is the crystallization or granulation of salt in your brine tank. When salt forms crystals or granules, they will remain at the bottom of the brine tank. In this state, they can do two things. You can stop the flow of water to the mineral tank or even halt the entire operations of the water softener.

Conclusion

This article is about the water softener and how it works. The article contains in-depth information on this water treatment system, starting from the various reasons you need a water softener to the merits and demerits of the water softener. Then, there’s information on the parts of a water softener, how the water softener works, from the ion exchange process to the regeneration process. Next, information was given on the types of regeneration cycles: co-current and counter-current regeneration cycles. Finally, we summed up the article with the various issues in regeneration.

About the Author

Paul Morton

Paul is a retired plumber who now spends hours on home improvement projects. From fixing toilets to leaking pipes in crawls spaces, there is nothing Paul can't do or wouldn't try. Paul was running his own plumbing company and is our expert in regard to all types of water filtration systems.

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