Best Water Softener for Tankless Water Heater

Best Water Softeners for Tankless Water Heaters

If you live in an area with hard water, a water softener is something to always have within reach. With hard water containing minerals (calcium and magnesium the most), it makes sense that, along with soap, this will lead to the formation of a filmy residue. In time, it can give your clothes and dishes a feeling of “uncleanliness,” which can only ruin them for good later on.

Top 10 Best Water Softeners for Tankless Water Heaters

   1. Magnetic Water Softener & Conditioner

When you don’t want to spend time installing a water softener for your tankless water heater, the Magnetic Water Softener & Conditioner is a valid option.

It’s the latest hydro-magnetic technology, and you don’t need to use any salt for it. The system includes rugged and tough Neodymium magnets that are incredibly strong. You don’t need any tools for installing the magnets. You don’t need to call a plumber nor make any modifications.

However, the system is going to reduce calcium, minerals, limescale which cause hard water spots. It’s made in the USA with solid steel, without any plastic casing so that you can see their strength. It has a galvanized base and triple coating with rubberized topcoat for weather resistance. It presents 360-degree surround magnetic field technology, and you can use it along with the salt-based system. You can choose between 7 sizes, according to your application. The system works for any size and material of pipes (iron, PVC, ABS, or copper).

It’s a great water softener to use for small homes, apartments, and mobile homes and it’s 100% portable.

Let’s check the right parts once again:

  • The system is made with high-quality Neodymium magnets
  • It’s very well made, reliable, and rugged
  • You can use it for all sorts of sizes and materials of pipes
  • It doesn’t require maintenance nor tools for install

The downsides aren’t deal breakers:

  • It may not give impressive results if the water is hard
  • You may have to wait for the results to show

Remember that you pay less than $30 for the system, and its efficiency may come as a surprise to many.

   2. KleenWater Tankless Hot Water Filter System

Anyone shopping on a tight budget should take a look at the Tankless Water Heater Filter, KleenWater KW2520SCALEX Tankless Hot Water Filter System.

The system is going to protect both tankless and traditional tank hot water systems since it’s made for pre-filtration. It contains a transparent water filter housing, wrench, bracket, and one polyphosphate water filter cartridge (2.5x20in), with the material being  safe for food and drinking. The phosphate ingredient reacts with calcium bicarbonate (naturally occuring) in the water supply, leading to a tight, thin, passivating, and non-corrosive film on the pipe wall. The film works as a glass coating which separates water from the hot water system/metal plumbing.

The filter is tight and gives 125psi maximum working pressure and 120-degree maximum temperature. It’s designed for cold water applications, and it’s perfect for tankless water heaters.

Despite its price, the system may be installed at the “point of entry,” ensuring anti-corrosion, anti-scale, and sediment filtration for the whole house. This way, you’re going to protect all plumbing elements and water from corrosive acid water and hard water.

The head comes with ¾” NPT inlet/outlet threads, presenting a 14-GPM flow rate. The filter is versatile, and it’s compatible with most brands of tankless water heaters and traditional tank systems (Ecosmart, Ecotemp, Rinnai, Atmor, Bosch, Norits, and so on).

Let’s check the positive aspects:

  • It’s versatile and compatible with tankless and traditional tank water systems
  • It’s made with polyphosphate which is suitable for food and drinks
  • It’s tough and rugged
  • You can use it for most brands of tankless water heaters

The downsides shouldn’t stress you out:

  • You may have to replace it after a couple of months
  • It only comes with 3.4”NPT

Beggars cannot be choosers, and the system prevents limescale and build-up from your pipes and tankless water heater efficiently. Isn’t that enough?

   3. Aqua-Pure Whole House Scale Inhibition Inline Water System

The 3M Aqua-Pure Whole House Scale Inhibition Inline Water System AP430SS is a versatile and dependable system for protecting your tankless water heater. It contains polyphosphates, which are going to block the scale build-up in tankless and traditional water heaters.

It’s also dependable for expanding the durability of hot water appliances, downstream plumbing fixtures, pipes, faucets, and showerheads.

The system features ¾” NPT inlet/outlet connections which ease out the installation, for increased flow rate (up to 10GPM). The pressure ranges from 25 to 125PSI, whereas the operating temperature ranges from 40 to 100F degrees. You can also install it on the cold water line feeding the water heater.

The build of the system is impressive, with the 304 stainless steel head perfect to install on current copper pipes. The system is made with corrosion-resistant material for a longer lifespan.  The single vessel/cartridge design of the system allows effortless installation for both professionals and non-professionals.

Remember to change the disposable filter every six months or whenever you notice a slower flow rate. You may adapt the filter to different pipe sizes thanks to the reducing adapter on either end.

Here’s our take on the pros:

  • It works for traditional and tankless water heaters
  • It’s versatile and allows adjustments to various pipe sizes
  • It contains polyphosphates
  • It’s not difficult to install

The cons shouldn’t worry you:

  • Some may think it’s not enough for the hard water in their home
  • Not everyone finds the installation effortless

The goods outweigh the bads, and the system is an excellent value for the money on any given day.

   4. Mobile-Soft-Water Portable Softener

Let’s say you want to take your RV for a drive, but you also need a water softener to use. The Mobile-Soft-Water Portable Softener is one of the many portable models to check, even though it stands out with the price and performance.

It’s a compact unit that saves a lot of space for storage, which means so much in a less generous RV. It’s an excellent choice for narrow spaces, short trips, and other applications. It’s a point-of-entry mobile water softener that conditions water of magnesium, calcium, lead, iron, radium, and many more heavy metals. It works with both well and city water.

Not only that the unit is portable and easy to carry around, but it also regenerates without using electricity. Installing and using the system isn’t complicated.

The unit may treat up to 5GPM of supply water with 10-grain total hardness. It comes with all the elements you need for the mount, and even one year limited warranty on materials. It improves the water taste and may filter all sorts of water.

Here’s our list of favorites:

  • It’s compact and highly portable
  • It\s easy to use
  • It works with well and city water
  • It improves the water taste

Don’t worry about the inherent flaws:

  • It may need some time to start running
  • It’s not able to handle a big house

We know that the system isn’t all roses and rainbows, but there are many other things to appreciate. The portability, the efficiency, and reliability are the selling points, and you should consider it for your applications.

   5. Electronic Water Softener System

Another solid choice for improving the performance of your tankless water heater is the Electronic Water Softener System – Chemical-Free House Electronic Descale.

It’s electronic water softener that is both reliable and effective for purifying the water for improving the quality of water. The tankless water filter softens the hard water without affecting the minerals while expanding the durability of your tankless water heater, pipes, and various appliances.

You can use the water softener for both hot and cold water for eliminating salts, impurities, and limescale from water. The system is also going to solve the problems you have with dry hair, itchy skin, or dull dishes.

The water softener comes with all the elements you need for installation. It’s small, so mounting it isn’t going to be a problem. It doesn’t require regular maintenance, and it’s easy to install. You also get a user manual for more details on install and use.

Here’s our opinion on the positive aspects:

  • It’s excellent for softener the hard water
  • You may use it for both cold and hot water
  • It doesn’t alter the taste of water
  • It comes with everything you need to install

We’re not making a drama out of the shortcomings:

  • The instruction could be more user-friendly
  • The connecting wire could be better

For those of you interested in using an electronic water softener, this one is going to be a wise investment for the long run.

   6. HydroFLOW-Eco-Friendly Alternative to Salt Water Softener

Did you ever try an alternative to salt water softeners? If not, you should give the HydroFLOW HS38 | Eco-Friendly Alternative to Salt Water Softener a try.

The system comes with advanced technology which treats water electronically for blocking the minerals build up to water heater, faucet, or pipe. In all fairness, the system cannot prevent the white scale/stuff, but it does prevent the minerals from collecting to the pipes and faucets.

You don’t need to make any plumbing alterations since the system is non-intrusive. The installation is a do-it-yourself project, and you may easily attach it to the incoming cold water line pipe. A system is a dependable option for pipes less than 2inches in diameter.

It’s an earthly friendly system that doesn’t use any chemicals for softening the hard water. It’s compatible with Galvanized, PEX, PVC, and Copper, and it’s maintenance-free as well.

Listing our favs:

  • It’s an electronic system
  • You can use it for copper, PVC, PEX, and galvanized fixtures
  • It’s easy to install
  • It’s maintenance-free

The cons aren’t major:

  • If you’re dealing with hard water, some other methods should be considered along with this system
  • Not everyone is happy with the results

As long as you’re managing to focus on the positives, the system can work for many tankless water heater applications.

   7. Hansing Whole House Water Softener System

Even if the Hansing Whole House Water Softener System may seem too much for a tankless water heater, you should check it anyway.

The salt-free water softener uses ¾” FNPT stainless steel threaded. The media is made from fruits polysaccharide and coconut activated carbon, which makes the system a healthier option to the chemical opponents. It doesn’t lead to scale and blocks minerals, odor, bad taste, and 99.5% of chlorine.

The high flow design also solves the problem of not working when the flow rate is lower than 5GPM. The housing is made with 304 stainless steel, with the o-ring sealing the build.

The system comes with mounting brackets and screws, whereas the installation isn’t complicated.

The cartridge’s lifespan depends on the water hardness and use, but you also get a wrench for future replacing of the cartridge.

You can use it for both well and city water.

Here’s the list of positive aspects to consider:

  • The system doesn’t use chemicals for softening water
  • It’s efficient and reliable
  • You can use it with well and city water
  • The cartridge lasts for five years or so

The minor issues are easy to overcome:

  • It doesn’t come with pipe fitting
  • Check to see if it’s not banned in your area

The system is active, dependable, and great to use for the whole house, not only for your tankless water heater.

   8. Anti Scale Systems for Tankless Water Heaters

Created especially for the tankless water heaters, the Anti Scale Systems for Tankless Water Heaters | Applied Membranes Brand is loaded with several positive qualities.

The 20” Big Blue Pentek Filter Housing comes with ¾” in/out connectors, easing out the setup. The Anti-Scale filter cartridge is made with A8210 anti-scale media which is highly efficient against hard water

The bracket is made with sturdy and heavy-duty steel, and it’s both durable and easy to mount. You also get Inlet Ball Valve, filter wrench for effortless cartridge change-out, and pressure relief button for efficient operations.

The filter comes entirely assembled, and it’s ready to install out of the box. The maximum pressure is 90psi, whereas the maximum temperature is 100F degrees, with a service flow rate ranging from 0.5 to 10gpm.

The system is going to improve the performance of the tankless water heater and expand its durability too. It benefits the downstream equipment and household appliances as well.

Let’s take a look at the good things:

  • It’s made for tankless water heaters
  • It comes ready to use out of the box
  • It’s efficient and reliable
  • It’s not difficult to mount

The shortcomings are minor:

  • It comes with ¾” in/out connectors
  • You still need to change the filter every eight months or so

Stay focused on the pros, since they’re many and try it next time you need.

   9. Triple Action Poly Salt-Free Water Softener

When you don’t want to get a filter every six months, the Triple Action Poly Salt-Free Water Softener is the right model for your needs.

The system is a salt-free water softener which comes with NSF Certification, and it’s BPA free. The system includes two-micron iron and bacterial filter, which explains its efficiency. It’s able to remove iron and intestinal parasites. You may confidently use it for well and city water, but not higher than 25 grains hard.

Unlike many of its competitors, the system is rather subtle and has a compact design. Once you install it, you may even forget it’s there. The bracket for the wall mount has a rugged build but doesn’t look bulky.

It’s an eco-friendly option too since you don’t have to get cartridges to replace. Anyway, the system comes with the recharge kit and Poly Salt-Free Sifter.

Let’s take another look at the qualities:

  • It includes two-micron iron and bacterial filter
  • You may use it for well and city water
  • You don’t need backwashing nor electricity
  • It’s compact and has a subtle profile

The pet peeves aren’t significant at all:

  • It’s not the cheapest water softener
  • Installation can get tricky

Despite the minor issues, the water softener is still a valid option to consider for your tankless water heater.

   10. Fleck Grain Water Softener

The Fleck 5600SXT 48,000 Grain Water Softener is a wise investment to make, especially if you’re using a pricey tankless water heater.

The system is a digital on-demand water softener and has paddle wheel meter. It comes with Fleck bypass valve and 1” male threaded yoke connection. It’s able to serve up to 12GPM service flow rates, softening medium to hard water.

The construction is impressive, and the system has a standard black brine tank with safety float. It features a high capacity resin and impresses with its durability feeling. It uses an ion exchange process for removing calcium and magnesium, the leading causes of hard water. The system also works on a meter based regeneration process. Therefore, the water is measured, and the system regenerated when needed.

Digital Control increases the efficiency and reliability of the system. The list of features continues with backlit LCD, touchpad controls, and 48-hour internal power backup. The interface is easy to understand, and everything about the system is high quality.

The tank comes with a 10-year warranty, and it’s made in the USA.

Let’s take a second look at the best parts:

  • It uses an ion exchange process for eliminating magnesium and calcium
  • It comes with impressive features
  • It has LCD and touchpad controls
  • It’s durable, reliable, and powerful

The downsides shouldn’t throw you off:

  • It may take you a couple of hours to install
  • You need to buy the drainage tubing

Regardless of the minor problems, the system is an effective and robust option which is worth every single penny.


Buying Guide for Water Softeners for Tankless Heaters

What does a water softener do?

A water softener is made for removing the calcium and magnesium while replacing them with sodium in a mineral tank with ion exchange. The soap isn’t going to leave a film anymore, but the water softeners may alter the lifespan of the tankless water heater (keep reading for the details).

What are the main advantages of water softeners?

If it’s the first time you’re thinking about using a water softener, here are the most significant benefits of water softeners:

  • They cut down the spending

Hard water presents a high level of calcium which is a poor heat conductor. Therefore, the scale builds up from the mineral in the hard water make the water heater to use more energy, to get to the desired temperature.

Therefore, the energy bill gets higher, and it’s just because the minerals in the water make the water heater work harder and more for heating the water.

The water softener system will block the developing of build-up, increasing the performance of the tankless water heater. When there’s no scale, the tankless water heater performs efficiently again.

  • The plumbing lasts longer, and the risk of clogs is reduced

But it’s not only the water heater that develops scale build-up from the hard water, and the plumbing can develop it too. Not only that the diameter of the pipes gets smaller (affecting the flow and efficiency), but the tubes can even last less.

The water softener eliminates the build-up and reduces the risk for messy clogs. Take it with a grain of salt, since the water softener may be useless when you pour grease down the sink.

  • You do less cleaning

Scale build-up is tough to clean, rending you to spend hours scrubbing in the bathroom. If you have hard water, it’s going to be everywhere in your house: pipes, coating the shower, the sink, and wherever it gets.

  • The laundry gets cleaner

Soap cannot lather very well in hard water, which is why you may have to use lots of it for getting the level of clean you desire.

When you use a water softener system, the clothes become soft and bright since the soap can lather and make them squeaky clean.

  • You get softer hair and skin

Forget about pipes, clothes, and sinks. Your skin and hair are going to be thanking you for using the water softener. Your hair isn’t going to be frizzy, dry, and your skin will not be dull anymore when using a water softener. Without the calcium and magnesium in the water, your hair and skin can look healthy and bright once again.

One last tip before you go shopping!

You should get all the information you need before buying. For instance, the salt-based water softeners have been around for more than a century, and stand out as the most affordable option. They eliminate the calcium and magnesium, replacing them with sodium ions.

You can also take a look at the salt-free water softeners (some professional raise a brow to the name), which don’t remove the minerals from the water. However, they still prevent the build-up of limescale and come in two different types: catalytic and electromagnetic.


FAQs about water softeners

Q: Do tankless water heaters also need a water softener?

A: Tankless water heaters are also sensitive to the hard water, even if the effects as less significant and don’t show that fast. With water running through the heat exchangers, the minerals drop out of suspension, with the majority of mineral disappearing while flushing. The build-up does need more time to develop, but it’s only a matter of time until it affects the performance of the tankless water heater.

Q: Is it difficult to install a water softener?

A: It’s always safe to get a professional plumber for installing a whole-house water softener onto the primary coming into the plumbing. The tankless water heater is going to last longer, and it’s going to perform better too.

Q: Does the scale detection eliminate the need for a water softener?

A: It’s only some manufacturers that make tankless water heaters with built-in scale detection. The feature only informs you when you need to flush the unit, and doesn’t eliminate the problems caused by hard water. Keep in mind that the scale detection is only available in the pricier models.

Q: Does the water softener take much space?

A: More often than not, you can install the water softener close to the main water inlet. For instance, if you install it under the kitchen sink, you will lose some space that you may very well use for storing something else.

Q: Do water softeners waste water?

A: It’s one of the main downsides. It’s common for water softeners to wastewater throughout the regenerations, which may increase the water bill up to 10%.  You only need to do it every couple of years, though, which makes it for the water waste.

Q: Is soft water as good as hard water?

A: It’s tricky since soft water isn’t great for cooking or drinking. You must have a separate tap for drinking, with many people choosing hard water over the soft type. For the water softeners that use salt, you may have to add rock salt any now and then, which means more spending. It’s a wash, and this is why you need to give it a good thought before using the water softener.

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