Water softener tablets and filter with a blue background.

How to Install a Water Softener (Step-by-Step)

A water softener can supply you and your family with cleaner water. This kind of unit helps fight sediment build-up, which can benefit not only your body but anything the water touches. You may find installers to hook up the system for you. But if you are the DIY type, you may prefer to install your new water softener yourself.

If you have the right skill set, water softener installation is a fairly simple process. So, you’ve picked out the desired unit from Amazon, it has arrived and you’re ready to get cracking. In this article, we will touch on the general guidelines for installing your new water softener.

Keep in mind that each water softener has a different installation process. Make sure to read any instructions provided by the manufacturer, and that you are following all the local plumbing codes. In this article, we will go over general guidelines for installing your new water softener. There are several kinds, so we will address each one in detail. The varieties of systems we will be covering include: 

  • Salt-based system
  • Salt-free system
  • Magnetic system
  • Reverse osmosis system

Replacing an Old Water Softener

If you are replacing an old water softener, the process is pretty easy since the plumbing is already in place. Before following the steps for installing the new one, first unplug the old one and put it into the bypass. Separate the plumbing from the unit. Place the system next to a floor drain and tip it over, allowing all the water to be drained.

You may consider saving the remaining salt that is in the brine tank. Then, dispose of the old softener. Continue to the following steps to install the new water softener. Let’s roll up our sleeves and put our plumbing skills to the test!

An electric heating element covered in limescale.

Limescale is a hard chalky deposit that often builds up inside kettles, hot water boilers, and pipes where hard water has evaporated.

Salt-Based (Ion Exchange) Water Softening System

We will start with the most common water softener: the salt-based system. If you are on well water, it is imperative to install a salt-based water softener due to the large amounts of hard water that can be found within it. The benefits of using such a system are improved hair and skin, softer, cleaner clothes, and is easier on your pipes and appliances.

Become familiar with how the water softener works to see if it is the right choice for you. Homeowners will find themselves less frequently needing to replace their plumbing system and appliances due to less sediment buildup. In the long run, you will find yourself saving money, though you may possibly see an increase in your water bill. Also, keep in mind that your sodium intake will go up as well. 

Installing the system for well water should work the same as for city water unless you have problems with the supply or pressure. If you do have these sorts of issues, it might be better to consult a professional to fix the problem. After the problem is resolved, then you can easily and safely install your system. Follow these steps to install a salt-based water softener system

1. Cut water supply and drain the lines:

Before getting started, make sure to turn off the mainline water supply to avoid causing a leak. Then turn off the electric water heater and power running to it to avoid damaging it. Next, drain any water from all the lines that will be involved.

The best way to do this is by opening the lowest valve in the house and letting the water run out. Also, be sure to open any faucets that are nearby to get rid of any lingering water. Now it is time to hook up your water softener!

2. Install brine tank overflow grommet (if applicable):

At the back of the sidewall of the salt storage tank, there is a diameter hole. This is where you will install the brine tank overflow grommet and elbow.

3. Place the softener:

Put the new softener into place, ensuring that it is standing level.

4. Cut into the main water supply line:

Find the area along the mainline where you want to install your unit. This must be before the line connects to the hot water heater. With a pipe cutter, cut into the main supply line. Tighten the cutter onto the pipe, rotating it around the pipe until it has been cut through. Place a bucket underneath to catch any water that leaks from the pipe. Sand down the edges.

5. Install bypass valve (if applicable): 

Typically, units will have a built-in bypass valve. If you need to install it yourself, follow these instructions, or the instructions presented by the manufacturer: Use silicone to grease the O-rings. Push the bypass valve into the softener as far as you can, then put the holding clips in place.

If your model doesn’t come with a bypass, we recommend that you get one. It is useful to shut off the water supply easily without cutting the whole house’s water. Be aware of any local plumbing codes that may require such a valve by law. Having one will make it easy to disconnect the water softener in an emergency.

6. Connect ports:

Next connect the lines of incoming and outgoing water to the outlet ports, which should be marked. Be sure that the flow direction is correct, otherwise, the unit will not work. Use hard or flexible tubing for the connections.

Flexible tubing is easier to set up, but you will need extra adapters. The push fittings will save you the step of soldering the materials. If you do decide to solder, however, make sure that the heat doesn’t melt any of the plastic parts. Seal threads with plumber’s tape unless otherwise specified.

7. Drain connection:

Salt-based water softeners must have a drain connection. This can be done by connecting the drain hose and the drain valve fitting, then use clamps to secure the hose. Secure the other end of the hose. Do not push the drain hose into the drain because it may siphon back wastewater. Make sure there is an air gap of at least 1 ½” or whatever is required by your local plumbing codes. There are air gap fittings that can be used for this.

8. Overflow connection:

To prevent the brine tank from overflowing, you will need to implement an overflow tube. This can be done by connecting a hose to the overflow valve, and then clamping it in place. Place the other end at the drain, securing the hose in place. Be sure to implement the air gap in compliance with your local plumbing codes.

9. Install brine line (if applicable):

You will need a brine line if you are using a side-by-side system instead of a cabinet-style softener. The brine line will enable the sucking of brine from the brine tank to the resin tank.

10. Fill with salt:

Put the brine well into the brine tank, then filling the tank with salt and possibly water if necessary. Refer to the manufacturer’s instruction in the right kind and amount of salt. Typically the tank should be filled ⅔ of the way. You can prevent salt from getting into the brine well by taping over it.

11. Sanitize:

Before using the system, it is a good idea to sanitize the system. You can do this by adding 1.2 fluid ounces of bleach per cubic foot of polystyrene resin into the brine well. Do this before and after backwashing the system. The bleach will dissolve in the brine and then be transported to the resin tank. Continue with normal regeneration.

You may need to add 2 or 3 gallons of water to the brine tank, depending on your softener. To do this, you must unplug the unit for 20 to 30 minutes till the brine has been used up in the brining process. It is best to keep the bleach in contact with the resin for at least one hour in order to sterilize the system completely. Rinse with a minimum of 75 gallons of water per cubic foot. Repeat this process every 3 to 12 months to periodically disinfect the system.

12. Use bypass as you turn on water:

First, open a nearby cold water faucet, then engage the bypass valve and slowly turn on the water supply. You must do it slowly because a sudden pressure increase can damage your plumbing. Check for leaks and wait till all the air has been flushed out.

13. Slowly open bypass valve:

Open the bypass valve slowly and partially, as you allow water to flow into the resin tank. Once the noise of the air running down the drain line stops, you can open the bypass valve fully. Then turn your electric water heater on.

14. Check for leaks:

Ensure there are no leaks in all the connectors, valves, and fittings.

15. Plug in and start:

Connect your water softener to the power source, then start a full regeneration cycle, starting with the backwash cycle. Follow instructions from your manufacturer particular to your model. Set the time of day, your hard water levels, and how often you want your softener to regenerate. Enjoy your soft water!

No salt written in salt with a black background.

The main benefit of salt-free water softeners is they don’t need any maintenance.

Salt-Free Water Softening System

Most people aren’t aware that salt-free systems don’t remove the hard water minerals the same way salt-based systems do. Salt-free systems transform magnesium and calcium chemically so that they do not cause scale buildup on surfaces. Since the minerals aren’t actually removed but instead altered, the salt-free systems are technically not water-softening, but instead water-conditioning.

However, a salt-free system still provides many of the same benefits of salt-based systems. A salt-free system prevents scale building, ensures softer, healthier skin and hair, and increases the efficiency of your appliances that use water. Though the benefits may not be as evident as with the salt-based system, you will find that a salt-free system is a much less hassle. 

There are many different kinds of salt-free systems out there. We will describe the typical installation process. However, be sure to refer to the manufacturer’s guidelines for detailed instructions. Here are some general guidelines for installing a salt-free water softening system:

1. Prepare the specified spot:

Clear the area you want your unit installed and set up the components.

2. Shut off the mainline water supply:

Turn off the water, then drain the pipes. You can do this by opening the lowest spout in the house and allowing the water to drain.

3. Cut the cold water supply:

Using a pipe cutter, cut into the cold water supply before the pipe reaches the pre-filter housing. Rotate the pipe cutter around the pipe to cut it.

4. Install shut-off valve:

Attach a shut-off valve to the pipe. You can do that by gluing it to PVC or by soldering it to copper.

5. Install carbon pre-filter:

Attach the carbon pre-filter using compression fittings after the shut-off valve.

6. Install second shut-off valve:

Attach a second shut-off valve using compression fittings, then extend the pipe to the distribution head of the filter.

7. Connect downflow outlet to cold water:

The downflow outlet of the system should connect to the pipe for cold water. This will allow the water to flow through the system, then through the house.

8. Close both shut-off valves:

Close both of the valves, then turn on the main water supply.

9. Open the shut-off valves:

Open the shut-off valves slowly one at a time. When partially opened, check the system for leaks. If you don’t find any, then open the valves all the way.

10. Start the system. 

Magnetic Water Softening System

Magnetic systems, like salt-free systems, do not soften water as salt-based systems do. However, they are much less expensive and have a long life. You won’t see any increased sodium intake in your diet, making the water good to drink and use for watering plants. The magnetic system prevents scaling, but not in places where water sits more than 48 hours, like your hot water heater. Installing a magnetic system is pretty simple and doesn’t require much technical know-how like other systems.

  • Figure out where to install the system: A magnetic water softening system is fairly small and can fit over your pipe. You can place it in a variety of areas where you couldn’t typically place a regular sized system.
  • Open magnet box: Your unit should come with instructions on how to open the box. Typically it will hinge on one side which enables you to clamp it down over the pipe. Place the box around the pipe, facing the direction that allows the water flow to pass through the box the right way.
  • Close the box around the pipe: Finally, close the box around the pipe using screws or nuts to keep it in place. These should be provided with the unit. 
A glass of clean water with osmosis filter and cartridges in a kitchen interior.

Reverse osmosis is a water purification process that uses a partially permeable membrane to separate ions, unwanted molecules and larger particles from drinking water.

Reverse Osmosis System

Water from a reverse osmosis system provides some of the best drinking water. It removes almost all contaminants from tap water such as lead, salts, colloids, pyrogens, and particulates. Some disadvantages are that they remove most of the minerals, leaving the water with an acidic pH. Additionally, a lot of water is used in the process of filtration.

These instructions may apply to you only If you have purchased a smaller reverse osmosis system. There are whole-house systems that must be sized according to the house. A smaller system can be placed under the sink to enable purified water to run through its own tap. How to install a reverse osmosis system:

1. Shut off and drain water:

Shut off the water below the sink. To drain the water, turn on the taps above the drain.

2. Determine the height:

The manufacturer’s instructions should mention the recommended height for the assembly of the filter. First, measure the walls to ensure the place for your system. Then mark where the filter will go and screw it in. 

3. Install saddle valve:

Unscrew the cold water line from the valve, then add the saddle valve with its filter. Then connect the cold water line into the top of the saddle valve. 

4. Connect water filter supply to saddle valve:

One end of the water filter line will connect to the saddle valve. Then attach the other end to the filter after cutting the tubing to the right length.

5. Attach supply and waste lines:

The system comes with supply and waste lines to attach to the faucet.

6. Attach faucet to the sink and install a drain line adapter:

Cut a small hole in the waste line, attaching the valve and line. They should run from the fitting to the faucet valve. 

7. Set your unit in place, connecting the supply lines.

8. Fill the system:

Make sure to follow the manufacturer’s instructions to fill the system. Then slowly turn on the faucet. Notice if there are any leaks. If not, fully turn on the faucet. You now have a working reverse osmosis system!

Water Softener for Home Improvement

Installing a water softener is a great step in home improvement. The salt-based, salt-free, and magnetic systems can reduce hard water, which improves the quality of hair and skin, clothes, as well as reduces limescale build up in your pipes and appliances. Reverse osmosis systems will provide you with the best drinking water, which has many health benefits. Whichever you choose, you will feel a sense of pride in your handiwork as a DIYer. Not only that, but if you choose to forgo the professional installation, a little more money will be left in your pocket. 

Joshua Perkins

Joshua spent ten years as a water systems technician in California before settling down with his wife and two young children in Nashville in 2018. Through all of his experience, he learned the benefits and shortfalls of so many different types of water filtration systems, from pitchers to whole-house installations. He started Water Filter Authority in 2019 to empower other families to make the right decision for their long-term health and wellness.