How Does a Water Softener Work?

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Water hardness is a prevalent issue in about 85% of American households. And while hard water is safe for our health, it causes other issues for plumbing fixtures, home appliances, and on hair and skin. A water softener is a common solution but many often wonder, “How does a water softener work?”.

Hard water flows into the water softener tank through a home’s well or main pipeline. Then it flows through a bed of resins. These beads are negatively-charged and attract the positive charges of hard water minerals, removing them. Softened water then exits the tank and through the pipe leading to the rest of your house.

While it may seem like you don’t need to know how this stuff works, knowing how it does its work can put many people’s minds at ease.

Below, we’ll go over everything you need to know about water softeners, including their main components and the entire water-softening cycle. We’ll also cover the essential regeneration cycle that keeps your unit in prime shape.

What is Hard Water?

Water is an everyday essential for all households across the world. No one simply survives without water. We use it for drinking, cooking, bathing, cleaning, etc. A clean, safe, and healthy water supply is a significant factor for many households.

Across the United States, households typically have two sources of household water: well water and city or municipal water. For an in-depth on the differences between these two water sources, check out our detailed guide here.

According to the United States Geological Survey, about 85% of households in the country have hard water and rely on it for daily drinking, cooking, bathing, and cleaning needs. This number is comprised of homes using either well water or city water.

Water hardness is determined by the presence and amount of dissolved minerals, specifically calcium and magnesium.

These minerals are naturally found in the ground. And when water travels underground, it naturally collects deposits of these minerals.

Hard water is prevalent throughout the country and it isn’t usually a major concern for risk. These present minerals are not toxic to people’s health and are safe to drink. Moreover, hard water doesn’t affect how water tastes and smells.

While consuming and using hard water is safe, it has its own set of negative effects on many households.

Effects of hard water

Hard water leaves behind deposits and mineral buildups on everything on its trail. This includes shower and bathroom fixtures, sinks, bathtubs, and home appliances that use water – coffee makers, dishwashers, washing machines, etc.

Though these mineral deposits are not harmful to humans, it is harmful to your appliances and plumbing fixtures. It can prematurely ruin your appliances, forcing you to replace them sooner than you actually need to.

Moreover, mineral deposits and scaly buildup from hard water leave behind a sticky film of soap scum and residue. This stains bathroom fixtures and clothes and make soaps, shampoos, and detergents less effective.

Worse, these deposits can build up inside your plumbing fixtures which would decrease water pressure and restrict water flow into your home. If you have well water, it’s likely you have hard water and should consider a water softener.

How Do I Know If I Have Hard Water?

There are many available at-home water test kits widely available. Prices range depending on the brand and kit inclusions but they’re fairly cheap.

If you want your water tested professionally, you can bring in a sample to a certified water-testing center and laboratory. This will give you a complete and detailed report on the state of your household water.

Other than these two testing options, keep an eye out for these telltale signs that you have hard water at home:

  • There are white-scale deposits on plumbing fixtures, sinks, bathtubs, plates, utensils, cutlery, pots, and more.
  • Prematurely damaged home appliances that use water to operate.
  • Soaps, shampoos, and detergents are harder to lather and you notice an increase in use.
  • Filmy and sticky soap scum and residue on appliances and home items after washing.
  • Dry skin and dull and brittle hair.

What is a Water Softener?

A water softener is a whole-house water filtering system that softens hard water.

What it does is remove traces of calcium and magnesium from hard water before it enters your home through different points. It does this through a process called ion exchange. This process removes natural minerals in the water that makes it hard so you end up with soft water instead.

When hard water enters the water softener’s tank, the calcium and magnesium ions present is replaced by sodium ions before entering your home.

The Components of a Water Softener

Before we talk about in detail how water softeners work, it’s important to know the basic components of one:

Water tank

The water tank is where all the magic of water softening happens. It’s a tall, narrow tank connected to your home’s water supply line.

Inside the water tank are small polystyrene beads – also called resin or zeolite – that are permanently sealed inside the tank.

This bed of tiny resin beads is what’s responsible for the ion exchange process. These beads are negatively charged and attract positive charges from the minerals in the water. The natural minerals then cling to the resin beads and the water is now softened.

The now-soft water exits through a water supply line and flows to your home.

Brine tank

There is a smaller, shorter tank adjacent to the water tank called the brine tank.

The brine tank assists the water filtration system for regeneration (a process we will discuss in detail later). In the brine tank is a solution with salt or sometimes potassium.

Once your home’s system has reached its maximum capacity of removing and absorbing hard water-causing minerals, the solution in the brine tank will regenerate it.

This tank is connected to another water line to dispose of the minerals. This also has a removable lid which you have to fill with sodium chloride or potassium chloride pellets when the time comes.

Control valve

While the two main components of a water softener are the water and brine tanks, there is a third yet equally important component – the control valve.

This is an electronic controller that has specific settings according to your household’s water use.

This measures the amount of water that goes through the system and into your house. And when it reads that the resin bed has reached its maximum capacity, it will initiate an automatic regeneration cycle.

The program and settings are based on a variety of factors like water usage, the size of the house, the number of occupants, and the water hardness level.

How Does a Water Softener Work?

The entire process of water softening can be intimidating to understand but it’s actually pretty simple to grasp. Here’s how a water softener works:

  1. Hard water flows into the water softener tank from a water pipe or well.
  2. The hard water flows through the bed of resin beads. There, the beads attract the minerals present in the hard water, effectively removing them.
  3. The now-soft water exits the tank and through the pipe leading to your home for use.

The Regeneration Cycle

How a water softener works don’t just end with delivering softened water into your home. There is also a process called the regeneration cycle.

After some time since your water softener has started working to deliver soft water to your home, it would reach its maximum water-softening capacity. By this time, the beads will be unable to attract and remove any more hard water minerals.

This means the resin beads would need to be recharged and rinsed to be brought back to their prime working capacity.

The regeneration cycle takes place in the brine tank. The cycle uses a salt-water or brine solution, which is the reason why homeowners add salt to their water softener units.

Here’s how it works:

  1. When salt is added to the water softener unit, a salty water solution (brine) is created in the brine tank.
  2. The brine solution flows through and enters the resin tank, where the resin beads are located.
  3. There, it will rinse the beads, exchanging the collected hard water minerals with new sodium from the solution.
  4. The brine solution leaves the resin tank with the collected hard water minerals through a drain or pipe.
  5. The bed of resin is recharged, renewed, and primed for softening hard water again.

The entire cycle could take a couple of hours and during this time, it is highly recommended that you will not use water as this can pose a problem for your water softener unit. To prevent inconveniences during the day, this is usually set at night when your home is not using water.

After the regeneration cycle, the system automatically goes back to water-softening mode.

Concerns About Water Softeners

While softened water is most definitely safe to drink, the release of sodium into the water is a major concern for many. But while there is an amount of sodium in the softened water, it’s a very small amount. It’s totally safe for drinking and wouldn’t pose major health risks.

However, it’s worth noting that this may especially be a problem for people on sodium-restricted diets.

The solution to this may be to use softened water only for activities where you will not consume or drink the water (cleaning, bathing, etc.). Some simply opt for potassium chloride for their brine solution instead of salt. The one drawback to using potassium chloride is a bag of it costs way more than a bag of salt.

Does a water softener remove iron?

While water softeners can remove some traces of iron in hard water, they’re not designed for this purpose. If your main water concern involves the presence of iron, a water filtration system specifically for removing such minerals shall be your best bet. Learn about the major differences between water softeners vs. water filters to decide which you need.

How Much Does a Water Softener Cost?

Modern ion exchange water softeners typically range from $500 to $2,000. The price tag depends on factors like brand, model, size, capacity, etc.

There is also the consideration of professional installation costs and salt or potassium chloride pellets that could easily add more to how much you will pay.

Installing one for your home can be pretty expensive but many homeowners see it as a worthy investment nonetheless.

Moreover, high-efficiency water softeners can last for over 20 years, enough time for your to get back your investment’s worth.


Hard water is a common issue across the country. Many rely on it for daily use. And while hard water is totally safe, it can cause a bunch of issues you might have trouble dealing with.

The solution many look into is a water softener system. Hard water enters the water softener tank through a home’s main pipeline. It will flow into the bed of negatively-charged resin beads where the positively-charged hard water minerals are attracted to and removed. The now-soft water flows through an exit pipe and throughout your home for use.

And that has been our detailed guide on the query, “How does a water softener work?”. Hit us up below if you have any more questions!

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