How Does a Water Softener Work

Hard water makes everyday tasks next to impossible. Have you noticed:

Dishes that are impossible to clean?
Clothes that are harsh and scratchy?
Sticky water?
Film on the shower, bathtub, or faucets?

Chances are you have hard water. We take water for granted so often that we forget that sometimes our municipal sources aren’t perfect (Flint, anyone?). If your municipal water supply produces water high in calcium or other minerals, the best solution is a water softener. This device helps millions of people around the world “soften” their water and put an end to all of the problems that hard water causes. The concept is simple but the science behind one is rather complex, so here we will cover:

How a water softener works
The two different kinds of water softeners (this is extremely important)
Why hard water is bad for the home
Typical signs you have hard water

What is Hard Water?

When water travels through the ground (particularly through limestone and chalk), small deposits of calcium and magnesium seep into it. When the mineral content of water is high, this is what is known as “hard water”.

While science has shown that water rich in minerals has moderate health benefits, it has negative consequences, especially in industrial settings. For example, businesses regularly monitor the hardness level of water to avoid costly breakdowns in equipment (boilers, for example). At your home, it also causes several costly and annoying issues. Your fixtures, dishes, and appliances are all at risk if the mineral content of your water is too high.

Any time that hardness is a problem, water softening must be used as soon as possible to prevent damage.

Why is it So Bad for the Home?

When water high in calcium and magnesium comes into contact with soap solutions, it forms deposits in your plumbing. Over time, these will clog the pipes and lead to a long list of other issues. Consider this finding:

Just a ¼ inch buildup on your heating coils can increase heating costs by 40%!

So not only do clogs put your appliances at risk and increase heating costs dramatically, it also poses problems for your:

Laundry
Dishes
Drinking Water
Hair and body
Pool

And just about anything else that has to do with water in your home. Pretty easy to see that it’s a major issue.

While you could get an expensive chemical treatment, the most affordable solution is a water softener.

How Does a Water Softener Work?

A water softener is a device that is connected to your home’s water system. It works on a principle called “ion exchange”. This trades the minerals in hard water for something else.

TERM - Ion Exchange: The process of removing “hardness ions” from the water (usually calcium or magnesium but sometimes iron as well) and replacing them with “softer” ones, typically sodium.

Calcium and magnesium in water both have strong positive charges. In a softening device, hard water is passed through a mineral tank that contains polystyrene beads (sometimes called resin). These beads are electrostatically charged with sodium. The calcium and magnesium ions bond to the beads, removing them from the water, while the sodium ions bond to the water. Voila! The exchange is complete!

What Happens Next?

Now that the beads are fully saturated with hardness ions, they can no longer soften any new water. That’s where the second tank comes into play. The “brine tank” makes the water in the resin tank salty again by flushing the resin tank with salt brine. This washes away the hardness ions and replaces them with new sodium ions. The device is now ready to start softening more water.

Here’s the process at a glance

Hard water enters the resin tank (full of sodium-charged beads)
The water and beads “exchange ions” because of their charges.
The hardness ions bond to the beads while the softness ions bond to the water.
Soft water is dispensed into your home.
The device goes offline.
Brine from the brine tank is pumped into the resin tank and flushes out the hardness ions.
The device comes back online and is ready to go again.

Salt-Based or Salt-Free Softener?

There’s an ongoing debate amongst businesses and homeowners whether a salt-based or a salt-free water softener is best. The issue is that most people think it’s an issue of preference—if you don’t like the taste of “soft” water, then there’s nothing wrong with switching to a saltless water softener.

This is wrong. And there are certain instances where you need a salt water softener or your home will still be at serious risk.

Here’s why:

Salt-Based Softeners: There are the typical models that we’ve already covered. Sodium ions bond to water and calcium/magnesium ions bond to the resin beads in the ion exchange process. You might not want one of these for two reasons: your are on a low-sodium diet or you don’t like the taste.
Salt-Free Softeners: Saltless water softeners are actually called “water conditioners”. They don’t actually remove the hardness ions from your water. They only make it so they don’t create deposits on your pipes. This solves most of the issues with hard water in your home and saves your appliances and fixtures from all of the problems high-mineral content water causes. These work fine when your hardness levels are low. Some models even come with internal filters that will filter the hardness minerals as it conditions your water.

When You Need a Salt-Based Softener

There are times when a saltless softener won’t cut it. Even if you don’t like the taste of soft water, you just need to deal with it. This is when your mineral content is very HIGH. If you have high hard water levels, you need a salt softener.

Most companies offer testing equipment to measure the hardness of your water. It’s done so in terms of grains per gallon (GPG). Anything within the range 60-120 GPG is considered moderately soft. If you are at the top range (100+), then a salt-based softener is recommended.

If the taste of the water or your sodium restrictions are that much of an issue, you can have a plumber reroute some of the water or install separate water filters on your taps to make the water better to drink.

Now that we’ve answered the question “how does a water softener work”, you need to find the best water softener on the market for your home.