Water Softeners: What are They and How Do They Work?

If you are among the millions of Americans living in homes with hard water, you’ve likely witnessed the chaos it can create in the household. Then on your quest for an effective solution, you probably heard that installing a water softener in your home is the most powerful way to defend against hard water and its destructive effects. But what exactly is a water softener, and how does it work?

Before we dive into that, let’s first explore some common problems caused by hard water in the household.

Common Hard Water Problems in the Household

Although hard water is not a health threat, it can wreak havoc in your household and sabotage your grooming routine. Hardness-causing minerals can build up in pipes, plumbing fixtures, and appliances, gradually clogging them and rendering them defective. For example, mineral scale buildup in faucets and water heaters may shorten their lifespans, decrease water flow in your home, and cut off the water supply to taps and appliances. Heck, some people even report hearing a “popcorn popping” noise in their water heaters, while some say their skin feels itchy after showering or bathing in water with high mineral content.

Hard water can also make it difficult to form a soapy lather, even with the most expensive shampoos, bathing soaps, and detergents. Instead, the hardness minerals combine with the soap to form a sticky scum that clings to your skin and hair, making them dry, itchy, and dull.

Another common hard water problem in the household is water spots on dishes, glassware, and silverware. (No, you don’t need a new dishwasher.) Hard water can also leave hard-to-remove stains on bathroom tiles, faucets, shower heads, glass shower doors, and other surfaces and plumbing fixtures.

But amid all these nuisances, a water softener has your back.

What is a water softener?

In a nutshell, a water softener is a filtration system that works to remove hardness-causing calcium, magnesium, and iron minerals from your water, essentially turning hard water into soft water. Like most people, you may have thought that all water is the same. However, that’s not the case. For instance, high amounts of magnesium, calcium, and iron in water absorbed from mineral-rich rock and soil make the water “hard.” But if the water lacks such minerals or has them in limited quantities, it is regarded as “soft.”

What are the different types of water softeners?

Water softeners come in several types, each using different processes and technologies to soften or condition water:

  • Ion exchange water softeners: Ion exchange water softeners, also known as salt-based water softeners, are the most popular water softening systems used in home applications. This type of water softener works by substituting sodium or potassium ions for hardness ions in hard water. Ion exchange softeners also have a large tank that holds the salt or potassium pellets used in the ion exchange and regeneration processes.
  • Salt-free water conditioners: As “salt-free” suggests, these systems don’t use salt to treat hard water. Instead, they rely on a mechanical filter to crystalize the calcium and magnesium and physically alter the minerals’ chemical structure. While salt-free softeners don’t remove the hardness minerals, the minerals’ new chemical structure renders them unable to form scale buildups and stick to pipes and surfaces.
  • Magnetic water softeners: Like salt-free water softeners, magnetic softeners don’t remove hard minerals from water. They neutralize the minerals to prevent them from bonding together, keeping them completely soluble.
  • Reverse osmosis (RO) water softeners: Generally, people don’t consider RO systems as water softeners, but these systems can strip water of many different chemical impurities, as well as calcium and magnesium that cause hard water. RO filters filter water through a semipermeable membrane that removes as much as 98 percent of water impurities.

If you want to learn more about the difference between salt-based and salt-free water softeners, we explain everything you need to know in this article.

What are the main parts of a water softener and their functions?

Ion exchange water softeners have three major components: a mineral tank, a brine tank, and a control valve. However, smaller capacity units combine the mineral tank and brine tank(s) into one cabinet. In contrast, larger flow capacity systems have a separate, stand-alone mineral tank and brine tank(s). Nonetheless, each system component works together to eliminate hardness minerals from water, monitor the water flow, and periodically initiate the regeneration cycle to clean the system and recharge the resin.

Understanding each component’s function will help you maintain the system correctly and potentially troubleshoot problems if you’re adept enough. With that in mind, here are the three main parts of a water softener and the function of each:

  1. The mineral tank: The mineral tank is a tall, narrow chamber where the actual softening occurs. The tank contains a sizable amount of plastic polystyrene resin beads, usually a few cubit feet.
  2. The control valve: The control valve is like a traffic cop in the water softening system. It determines when it is time to clean the resin beads now coated with hardness minerals.
  3. The brine tank: The brine tank is a shorter tank sitting adjacent to the mineral tank. The brine tank stores the highly concentrated sodium or potassium solution to recharge the beads. Salt or potassium pellets (or blocks) are manually added to the brine tank, dissolving in the water at the bottom of the tank.

How does a water softener work?

Since the ion exchange type is the most commonly used water softeners today, we’ll refer to it for this explanation. A standard water softener uses ion exchange to remove hardness minerals calcium, magnesium, and iron from water by replacing them with sodium chloride (salt) or potassium chloride.

Here’s a quick explanation of how the system works:

  1. When the hard water enters the resin tank (or “mineral” tank), it percolates down through a bed filled with plastic-like resin beads. These beads, typically made from polystyrene, have a negative charge and are coated with positively charged sodium ions.
  2. The negatively charged resin beads attract the positively charged hardness minerals as the water passes through the tank – because, as you probably can recall from science class, opposite charges attract.
  3. As the hard water passes through the resin, the hardness ions cling to the beads, and the now-softened water exits the softener tank, ready to be pumped throughout the house.
  4. Sooner or later, the resin beads become saturated with hardness ions and can’t attract any more mineral ions. Hence, the beads must be “recharged” by removing the mineral ions attached to them during the water softening process. At this point, the system must initiate a regeneration cycle to clean the beads in the mineral tank, recharge them and prepare them to soften more water. This is where the brine tank comes in. Some water softeners have onboard computers that calculate the amount of water that has flowed through the softener. When it reaches the preprogrammed setting, regeneration automatically begins. Older-style softeners use a timer-based process that initiates the regeneration process after a specified time. Newer models track the actual water usage and use it to determine when it’s time for regeneration.

How the Water Softener Regeneration Cycle Works

The regeneration process consists of three cycles: backwash, recharge (regenerate), and rinse. This process usually occurs every few days, typically in the middle of the night. Here’s how it works:

  1. Backwash: Regeneration begins with a back washing cycle in which the valve reverses the water in the tank and flushes the tank of debris. The cycle eliminates dirt and debris caught in the softener through the drain connected to the municipal sewer system or septic system.
  2. Recharge (regeneration): During the regeneration cycle, the salty water is pumped from the brine tank into the mineral tank. The highly concentrated salt solution forces the magnesium and calcium ions off the beads, and the mineral-rich salty water is then flushed out of the tank and down the drain. Essentially, the high concentration of sodium ions in the saline brine solution displaces the calcium and magnesium ions on the resin beads, coating the resin beads with sodium ions once again. The salty rinse water and all those unwanted mineral deposits are flushed out of the discharge hose into the drain.
  3. Rinse: A rinse cycle commences, in which the mineral tank is filled and rinsed with water. The system then automatically reverts to softening the incoming water.

Water Softener Regeneration Methods

Water softeners regenerate using one of two methods: co-current or counter-current regeneration.

Co-current regeneration cycle

In co-current regeneration, the brine solution enters the mineral tank in the same direction as the service flow. The brine solution (containing sodium or potassium) flows into the resin, after which an ion exchange process occurs again. But this time, the exchange happens in reverse. The aim is to use the positive sodium ions in the brine solution to replace the magnesium and calcium ions attached to the resin beads. So, as the brine flows over the beads, the salt forces the beads to release the magnesium and calcium ions in exchange for the sodium ions. As more brine passes through the resin, large concentrations of hardness minerals form and exit the system as the brine solution pushes more hardness minerals through the bed. Continuous exchange and re-exchange of minerals and regeneration occur until all the hardness ions are removed, completing the regeneration process.

Counter-current regeneration cycle

In counter-current regeneration, the water enters the tank through the bottom of the mineral tank, where the water usually exits. Typically, counter-current regeneration uses about 75 percent less salt and 65 percent less water than co-current cycling. During counter-current regeneration, the brine solution is forced up the resin bed from the bottom of the tank, where the beads are usually less depleted. This means fewer hardness minerals are present to begin the re-exchange process during the regeneration cycle. The brine is also less depleted by the time it reaches the top of the resin bed, where hard water first enters the softener.

Please Note: The regeneration process slowly dissolves the salt or potassium chloride pellets in the brine tank, so, at some point, you’ll have to add more pellets to the tank. How often you’ll need to replace the pellets depends on how much water you use.

What do water softeners remove from water?

Water softeners mainly remove calcium and magnesium from water, the two main culprits responsible for making water hard. The ion exchange process also targets and eliminates any positively charged ions, including other minerals like iron and manganese. However, water softeners only remove ferrous iron (dissolved iron) when it is in low quantities, and most of the iron is in a soluble state. Ferric iron (insoluble iron) is more difficult to remove with a softener because it will accumulate on the resin bed and resist the back washing cycle. Any remaining ferric iron in the system can produce slugs of iron in your water and make the resin beads less effective. It’s also worth noting that when dissolved iron is exposed to oxygen, it oxidizes and turns into ferric iron. That means even though a water softener can remove dissolved iron if you have high iron levels in your water, some of it will convert to an insoluble state. Here, the trick is to use a suitable chemical solution to cleanse the softener bed and protect the resin bed. You can also use an iron filter or a reverse osmosis system to remove iron from your water.

Water Quality Problems a Water Softener Won’t Fix

While water softeners do a darn good job of removing calcium and magnesium from hard water, they cannot remove other minerals, gases, chemicals, and other pollutants that can cause drinking water problems. For instance, water with a faint “rotten egg” smell contains dissolved hydrogen sulfide gas, but a water softener does nothing to remove this smell. Beyond that, a water softener doesn’t remove heavy metals, like lead and copper. Consequently, you must have a water treatment system designed to eliminate these additional contaminants, as a water softener won’t remove them.

Is it safe to drink soft water?

Soft water is generally safe to drink. However, the sodium ions released from the resin beads during the ion exchange process may be a problem for some people living in areas with extremely high water hardness levels. Typically, the amount of sodium in softened water is negligible. For example, if you have moderately hard water, that’s five grains per gallon (or about 86 ppm), which equates to 37 milligrams of sodium added per quart of water. That’s less than 2 percent of the suggested daily sodium intake. However, if you live in an area where the water is extremely hard (your water has a hardness level of over 200 ppm), you might be ingesting too much sodium through your drinking water. And of course, this could be bad for people with hypertension and those concerned about their overall sodium intake. Sure, some resins use potassium chloride (a better alternative to sodium chloride), but potassium chloride salt is often more expensive.

Should I invest in a water softener?

Deciding whether to invest in a water softener is a matter of personal preference. If you see signs of hard water in your home, you may need a water softener. But if not, you probably don’t need one.

Bear in mind that if your water is hard, the hardness won’t go away on its own, and the damages and costs incurred by hard water will continue to escalate. Without a water softener, the scale will continue to accumulate in your pipes, restricting your flow rate and increasing your risk of losing water pressure throughout your home. Hard water can also shorten your appliances’ lifespans, such as water heater(s), which may cause your utility bills to skyrocket. On top of that, if your water supply is hard, the ongoing repairs and replacements won’t cease until you install a water softener to safeguard your home.

How much does a water softener cost?

Whole-house water softeners generally cost about $500 to $2,000, depending on the unit’s type, quality, and several other factors. And don’t forget the installation cost (if you decide to hire a professional). Nonetheless, if your home has extremely hard water, a water softener is a crucial investment. Plus, water softeners typically can last for 15 years or longer with proper maintenance – despite the price tag. Some models also carry low maintenance and operational costs.

Furthermore, water softener resin can last much longer if back washed adequately. The only real monthly cost is replenishing the brine tank with sodium or potassium chloride. Based on industry standards, a family of four using a standard water softener will use about 40 pounds of salt each month. However, water with high TDS (Total Dissolved Solids) content and iron levels will require more salt to soften water effectively. A 40-pound bag of sodium chloride pellets ranges from $10 to $25. You can also upgrade to a high-efficiency counter-current brine unit, which will use even less salt or go with a salt-free water conditioner that uses no salt or potassium.

When you consider the high expenses and daily frustrations of dealing with hard water, a water softener is ultimately an investment that will not only save you a considerable amount of money but will aid your mental health (literally).

When to Install a Water Softener

If you observe signs of hard water in your home (clogged pipes, stains on kitchenware, dry hair, skin, etc.), it may be time to install a water softener. However, to ensure that hard water is the culprit, we recommend using a hard water test kit to check your water supply for hardness. You can also contact your local water provider and request a copy of their latest water quality report. This report usually includes vital information about your community’s water quality, but make sure you learn how to read and understand a water quality report beforehand. Some of the terms can be technical for some people.

We provide more information on conducting hard water tests in our article, “3 Easy Ways to Test for Hard Water and How to Measure its Hardness Level.”

Where to Install a Water Softener

Ideally, you should install your new water softener as close to the water’s point of entry into the house as possible – preferably somewhere where it’s “out of the way” and easily ties into your home’s main water line. In most cases, this is a basement, garage, utility room, or another dry, level location before the water heater. The system will also need to be close to an electrical power outlet and a drain to discharge the brine solution from the regeneration cycle.

Two other crucial precautions are to allow adequate space around the unit for easy servicing and install a bypass valve in your plumbing if your water softener doesn’t have one built into the inlet and outlet. A bypass valve helps to redirect water flow away from the device, which is very useful if you need to maintain the unit or install it without disturbing the water supply to the rest of the household.

When it comes to areas where you should never install a water softener, number one on the list is anywhere freezing might occur. Water softeners and freezing temperatures don’t play well because such conditions can cause damage and void your warranty. If temperatures are expected to drop below 40 degrees F (4 degrees C), drain the system and relieve pressure from it to protect it from damage. Also, avoid installing the system outdoors, especially in direct sunlight.

Now that you know the best (and worst) places in your home to install your water softener, the next step is installing it. Prepare to get your hands dirty!

How to Install a Water Softener (DIY Installation)

Most manufacturers recommend finding a good plumber to install a water softening system. But today, we’ll explain how you can safely tackle this project by yourself.

Steps required:

  1. Prepare the area. Clear and sweep the installation site to remove dust and debris.
  2. Align the water softener. Ensure that the system is positioned correctly with the inlet connected to the water supply and the outlet facing the water heater’s direction.
  3. Shut off the water to your house at the main water line. The last thing you want is water spewing from the pipes during the installation process. To prevent this, shut off the water supply to your home and turn off the power and water supply to the water heater.  
  4. Drain the water lines. Open a couple of bottom-floor faucets or hose bibs to ensure all the water exits your house’s water supply.
  5. Cut into the main water supply line with a pipe cutter. Use a pipe cutter to cut into the water-main leading into the supply line. Since you are installing a whole-house softening system, you need to connect the inlet and outlet lines directly to the main water line.
  6. Measure, cut, and install the pipes. Measure and cut the pipes to fit and solder on any nipples and fittings before connecting the pipe to the bypass valve.
  7. Clamp the drain hose to the softener, then feed it to where it will drain. Because the water softener needs to discard the brine solution after the regeneration cycle, you must clamp the drain hose securely and feed it into the dedicated drain. The end of the hose will need to have at least two inches above the drain hole to prevent back siphoning of the wastewater.
  8. Connect the brine tank’s overflow tube. Overflow tubes also help to prevent the brine tank from flooding and overflowing. Refer to the manufacturer’s guide for instructions regarding height and placement.
  9. Power on the system, turn the valve to the “bypass” setting and flush the water through the system to remove any sediment or debris. Open the valve very slowly to let in the water while releasing any air in the pipes. Follow the manufacturer’s instructions for setting up the flushing schedule and for adding salt to the tank.

Note: The steps above outline the standard installation process for a whole-house water softening system. Be sure to read and follow the manufacturer’s instruction guide for your water softener, as some water units are designed differently and have varied installation processes.

Do water softeners require maintenance, and how long do they last?

Water softeners do need maintenance to function at peak performance. Salt-based softeners require that you add additional sodium chloride to the brine tank periodically. But if you are concerned about the sodium content in soft water, you can add potassium chloride instead. Potassium chloride is considered a healthier alternative, but it is usually more expensive than sodium chloride. Luckily, salt-free systems, like our FutureSoft FS1 Salt-Free Water Softener, usually require less maintenance since they don’t use any salt or electricity, nor do they waste water.

Generally, water softeners can last about 15 years, but they can last much longer with proper maintenance. Ensuring the brine tank never runs out of salt and protecting the resin bed from high iron and manganese levels will protect the unit and extend its lifespan. Resin cleaners can enhance the regeneration cycle and help relieve the beads of hard minerals.

Usually, resins can last about 10 to 20 years if maintained well, but chlorinated water can quickly exhaust the beads’ ion exchange capacity. Sediment can also cause damage to the screens and injectors within the control valve, so it’s wise to install a sediment filter before your water softener, especially if you are on well water with lots of dirt and debris. We must also note that if your home has extremely hard water (over 14 grains per gallon), your water softener may not last as long as someone softening moderately hard water.

Considering all the factors that can affect a water softener’s performance and softening capacity over time, it’s difficult to determine a specific time frame for replacing the system. However, if your unit is over a decade old and you notice that its softening powers seem to be consistently declining, it may be time to invest in a new system. But overall, thorough care and maintenance can significantly extend a water softener’s lifespan.

Final Thoughts

Water softeners are an effective filtering solution used to treat hard water. Traditional water softeners use ion exchange to remove minerals from water by reversing the natural processes through which water becomes hard in the first place. In contrast, salt-free systems don’t remove the minerals but use a physical process to change the minerals’ chemical structure so they cannot stick to surfaces and damage pipes and appliances in your home.

With all the disastrous effects of hard water in the household and the incredible benefits of water softening systems described in this article, it’s clear that a water softener can be an asset to homes, especially those in areas with extremely hard water. And considering that over 85 percent of Americans have hard water, we need the protection of these systems now more than ever.

If you want to learn more about water softening or need help choosing the best water softener for your home, please give us a call at 800-589-5592 or send us a message today. We’ll provide all the information you need and help you find the ideal system for your home and budget.