How to Install a Water Softener

Just purchased a water softener for your home? Don’t be so quick to call the plumber – you can install the system yourself with a bit of time and patience.

Providing you have a basic grasp of DIY and an ability to follow instructions, you should be able to install a water softener within 2 to 4 hours.

All water softeners are different, and it’s important to consult your user manual for specific product information. However, most will require the same basic installation process.

Learn more about installing a water softener in this simple step-by-step water softener installation guide.

🧰 What You’ll Need

Before you get started on installing a water softener, you need to have the right tools and materials for the job.


The tools you will need are:

  • Slip joint pliers
  • Plumber’s tape
  • A tape measure
  • Pipe cutter
  • Torch and solder


Your water softener might not come with all the materials needed for installation. Check whether you need to buy the following:

  • Flexible tubing or copper tubing
  • Adaptors and fittings
  • Valves and tees
  • Drain tubing
  • Air gap fitting

🤔 Where to Install a Water Softener

Most water softeners should be installed in a basement or garage depending on where you live, as close to a home’s point of entry as possible.

If you don’t have enough space for an indoor installation, you may also be able to install a water softener outdoors.

water softener installed outdoors
Example of an outdoor installation

Typical Basement Installation

When installing a water softener in your basement, place the system as close to the entry point of the incoming water pipe as possible.

You should place the softener upstream of your hot water heater. This will stop hard water scale from damaging the heating appliance, and provide hot and cold soft water to your home. It will also prevent hot water from causing damage to your water softener.

Outdoor Installation

Outdoor installations require a little more forethought. Most water softeners can be put outside, but it’s best looking for one that is specifically advertised for both indoor and outdoor use.

You’ll need to protect your water softener from the elements. Rain, snow, icy temperatures and direct sunlight can all damage the exterior of your system and shorten its lifespan. Humidity and freezing can also affect the contents of the brine tank, which may hinder the performance of the unit.

You can buy covers and enclosures for an outdoor water softener, or you could construct your own housing. Ensure the whole system is protected against water damage, including any pipes and cables. Install the system on the side of your house, as close to your water’s point of entry as possible.

📝 Water Softener Installation Step-by-Step

Once you know where you’re installing it, you can learn how to install a water softener at your water supply.

Step 1: Preparation

By this point, you should already have the tools and equipment you need to install a softening unit. You can now carry out pre-installation.

First, switch off your water supply. This will stop water from escaping your plumbing and causing leaks while you install the unit.

If your home uses an electric water heater, you should also turn this off too as a precaution.

Open the faucets in your home to drain out any lingering water.

shut off main water supply

Step 2: Install Overflow Grommet

Once you’ve carried out the pre-installation tasks, you can now start on hooking up the unit.

If your salt-based water softener uses a brine tank overflow grommet, that’s the very first thing that needs to be installed. At the back of the brine storage tank sidewall, you’ll find a diameter hole where the grommet and elbow should be placed.

install overflow grommet

Step 3: Cut Into Pipe

Next, use a pipe cutter to cut out a section of the pipe in your water supply. Ensure you take careful measurements beforehand to properly locate the softener. Sand the edges of the cut pipe and use a lint free cloth to remove any dust and catch any leaking water with a bucket or container.

cut into pipe with pipe cutter

Step 4: Attach Bypass Valve

Your next task is to install the bypass valve. Some water softening systems have built-in valves that don’t need to be installed. Consult your user manual to check what type of valve your softener uses.

To install the bypass valve, use silicone to grease the O-rings provided and insert the valve into the softener valve, pushing it as far as you can. It should click or snap into position.

If your water softener doesn’t come with a bypass valve at all, I recommend buying and installing one. With this simple mechanism, you’ll be able to shut off the cold water in your plumbing when you’re performing maintenance on your softener. In some parts of the country, it’s illegal not to have a bypass valve that can be used to divert your water in an emergency.

install shutoff valve

Step 5: Connect Outlet & Inlet Ports

Your water softener should have marked inlet and outlet ports that need connecting to your ingoing and outgoing water supply. You can now attach these ports, following the instructions in your user manual.

It’s essential that you don’t mix up the inlet and the outlet sides, as this will prevent your water softener from being able to produce soft water. It’s an easy mistake to make, so double-check before you move on.

You can choose either hard piping or flexible tubing to connect to the ports. While hard piping doesn’t need additional adaptors, flexible tubing is typically much quicker and easier to set up, and you won’t need to take your soldering gun out for the job. Flexible tubing can be removed and replaced more easily, too. Just make sure to use plenty of plumber’s tape to seal the connections, whichever choice you opt for.

install inlet and outlet ports

Step 6: Connect Drain Hose

Event the best salt-based water softeners waste a measured amount of water during regeneration, and for that, they require a drain connection.

To install the drain line, connect the unit’s drain valve to the drain hose. To secure the drain hose, use clamps. Next, connect the bottom end of the hose to a suitable drain and secure it in position.

The majority of drain hoses shouldn’t be inserted fully inside the drain, as this increases the risk of back-siphoning. To stop wastewater from entering back into your unit, you will need an air gap of at least 1.5 inches.

Purchase an air gap fitting for the job and consult the manufacturer’s guidelines carefully during installation.

connect drain hose

Step 7: Set Up Overflow Connection

To prevent the brine tank from overflowing, your water softener should come with an overflow connection. To attach this to the unit, locate the overflow valve and attach a hose, securing it in place with a clamp.

Again, direct this hose to the nearest suitable drain and secure it down, preventing it from moving out of place. Check whether you need an air gap. If so, you will need to buy another fitting.

connect overflow drain hose

Step 8: Connect Brine Line

If you have a side-by-side water softener, consisting of a brine tank and a resin tank, a brine line is needed to transport salty water into the resin bed. Follow the manufacturer’s guidelines to install this line.

connect brine line

Step 9: Post-Installation

Water softener units all require slightly different setups once they’ve been installed. If you have an electric water softener be sure that you are plugging the unit into a GFI outlet. Generally, your next steps will be to fill the brine tank and program the unit’s settings.

To start with, your water softener will require salt. Place the softener brine well in its place in the brine tank, then pour softener salt into the tank until it’s about two-thirds full. Consult your user manual for information on the best type of salt and the exact amount required.

how much salt to put in water softener

Next, check whether your water softener needs to be sanitized before use. The guidelines for doing should be outlined by your manufacturer.

It’s now time to test the unit. Put the softener into bypass, then switch on your water and open a nearby faucet, being careful not to do this too quickly. You don’t want to damage your pipes and plumbing with a sudden burst of pressure.

If there are no leaks, allow a couple of minutes for any trapped air to be released. Then slowly open your water softener’s bypass valve to allow water to make its way into the tanks. You will hear a noise as air leaves the unit through the drain. Once this noise has stopped, you can open the valve all the way.

Switch your water heater back on and check your plumbing, fittings, connections, and pipes for leaks. You can then plug the water softener in, program a regeneration cycle, and input your water usage/water hardness settings. The softener will now be ready to use in your home.

🧐 Frequently Asked Questions

Is installing a water softener expensive?

The cost to install a water softener depends on a number of factors. The best-case scenario is that your system will be sold with everything you need for setup (including the right adaptors and fittings), you’ll have all the tools required already, and you’re confident enough in your DIY skills to install the system yourself.

On the other hand, you could end up spending a few hundred dollars on installation parts, tools and accessories; even more if your home doesn’t have a plumbing system that’s easily accessible. Paying for a plumber will also significantly add to your overall installation costs.

In short, installing a hard water softener may be expensive for you, but it may also be more affordable. You can expect to pay anything from $300 to $1,500 on a water softener installation.

How long does water softener installation take?

This depends on your own DIY experience and know-how, and the complexity of the unit itself. The accessibility of your home’s plumbing system will also affect the tasks that are required during installation, and the speed at which you can get the job done.

If you know how to handle tools, your user manual’s instructions are clear, and your water supply line proves simple to hook up to, you could install your water softener in 2 hours or less.

On the other hand, if you spend ages poring over the user manual and trying to figure out what you’re supposed to be using your tools for, or your plumbing isn’t easy to access, you’re more likely to take upwards of 4 hours on the job.

Is installing a water softener hard?

For homes with accessible plumbing, no. Installing a water softener is just a case of making sure you have the right equipment for the job, then carefully following the step-by-step guidelines in your instructions booklet. As long as you stick to the guide, you shouldn’t find the process too difficult.

how to hook up a water softener

There are things that can increase the difficulty of a DIY installation, however. If you don’t have the right tools and parts for the job, and it isn’t clear what you do need, installation might become complex before you even start. If your home has old plumbing, it may also be trickier to cut the main line and connect the water softener to your water supply.

If in doubt, contact the manufacturer. They can offer information about the softener and answer your questions before you make a purchase.

Can I carry out DIY installation with no previous handy experience?

If you’ve never taken on a big DIY project before, there’s no reason why you shouldn’t still install a water softener yourself. Double-checking every step before getting started will take longer, but it’ll ensure that you don’t make any errors, and you’ll end up with the same professional result as a plumber could provide.

However, if you can’t get your head around the installation process, and neither the instructions booklet nor online videos help, I would advise considering hiring a  licensed plumber.

There should be no guesswork involved in setting up the system. Your installation cost may end up skyrocketing if you have to pay to replace a damaged section of your plumbing or purchase a new softening system because of a mistake you made along the way.

How to install a water softener to replace an old one?

Installing a water softener to replace an existing unit is very easy. You’ve already done the hard work of cutting into your water line, plumbing the system in, purchasing the right fittings and connections, and so on.

Unless your new system is drastically different from your current softener, installation will be as simple as swapping one system for another.

Simply put your existing water softener into bypass mode, then unplug it and disconnect it from your plumbing. You can then follow the setup instructions in this guide for your new water softener.

Before disposing of your old water softener, tip it up over a drain to empty out the water. Any remaining salt in the brine tank can be saved for using in your new system.

Who can install my water softener?

If you can spare the extra installation cost of getting a professional to hook up your water softener for you, you have several options.

Most retailers like Sears and Home Depot will provide an installation service at an extra fee. However, buying a water softener from a hardware store is often more expensive than purchasing the same one online, so I would advise against this if you’re still considering your options.

The second option is to hire a licensed plumber for the job. This gives you the advantage of being able to shop around in your local area and choose a contractor after looking at customer reviews and considering cost. Remember, you’re looking for a professional, high-quality job, so you don’t want to go for the cheapest contractor in the area if they have a reputation for cutting corners.