How to Install a Whole House Water Filter System (Incl. Diagram)

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A whole house filter system delivers clean water throughout your entire home so that you can enjoy delicious drinking water at every tap, chlorine-free showers and brighter clothes.

However, this type of water filter requires proper installation that involves plumbing. Sounds scary? It doesn’t have to be! Getting everything up and running is only moderately difficult. And with the right tools and enough time & patience you should be able to do the setup yourself.

Just got an idea for your next DIY project? Great! The following article will provide you with everything you need to know.


Key Takeaways

Follow these steps for installing a whole house water filter:

  1. Shut off the water supply and release pressure from within the pipes by opening nearest outlets
  2. Remove pipe section from main water line
  3. Optional: Install valves and gauges
  4. Install the whole house filter
  5. Turn the water back on, flush, and check for leaks

Location – Where to Install a POE Filter?

The first question that needs to be answered is where you should install your new whole house water filter.

Of course you want to choose a location close to where the main water line enters your home so that you have filtered water at every outlet. The only exception are outside faucets that usually don’t require filtered water – but that’s up to you!

You also want a location that’s easily accessible so that you can service your filtration system – mainly replacing cartridges – without hassle.

Somewhere near the main shut-off valve and upstream of the water heater is probably your best bet. This will increase the heater’s lifespan and the longevity of all your household appliances running on hot water as they do not have to deal with sediment, lime and all that jazz anymore that might be present in your water supply.

If you are on a private well make sure to install the filter system after the pressure tank.

Our top POE water filter system? It depends on your situation. Check our reviews of the best whole house water filters to learn more.

Before or After Water Softener?

Should you install your new whole house unit before or after the softener (if you have one)?

For municipal supplies before the softener to protect the ion exchange media from chlorine and rule out potential pressure issues.

For well supplies some experts say after the softener to ensure full flow when backwashing. Also, unless you chlorinate your well, your water won’t contain any chlorine that would require removal.

Is Outside Installation a Good Idea?

Outside installation is not completely out of question, but placing your whole house filter in your garage or basement is the better option.

Installation Diagram

Here is a little installation diagram that you mind find useful:

Whole House Water Filter Installation Diagram

Parts & Tools

This is a list of tools, parts and installation accessories that you are going to need:


  • Filtration system with the different components
  • Mounting brackets (not all)
  • Tubing
  • (Push) fittings
  • Shut-off valves
  • Bypass valves (optional)
  • Pressure gauges (optional)

Required Tools

  • Drill
  • Drill bits
  • 2x adjustable wrench
  • Pipe cutter or hacksaw
  • Bucket
  • Teflon tape
  • Screwdriver
  • Solder supplies (optional)

How to Install a Whole House Water Filter System

The good news is that no matter which model you choose, the fundamental process of installing a whole house water filter system is always the same. If you are handy around the house, the entire setup shouldn’t take more than one afternoon (2 to 4 hours).

Here are some step-by-step instructions:

Before you start, carefully read the manual and make sure that you comply with local plumbing codes. When in doubt about your next step consult the manufacturer.

  1. Start by shutting off the main water supply.
  2. Drain all remaining water by opening all faucets and fixtures. This will also release pressure.
  3. Cut into the main line. Remove a large-enough section of the pipe to accommodate your filter system with all its components. Have a bucket at the ready to prevent spilling.
  4. Sand the burrs of both ends of the cut pipe.
  5. Remove any debris from inside the pipe.
  6. Install one shut-off valve on either side of the system for ease of maintenance. Also consider adding a whole house water filter bypass valve so that you have water in your home even while the system is in service mode. Shut all valves for now.
  7. If you want to be able to monitor input and output pressure install a pressure gauge next to each shut-off valve. This way you know at a glance when it’s time to change filters.
  8. If necessary, attach a piece of plywood to the back wall for easier mounting.
  9. Now it’s time to install the system itself. This will require a lot of dry fitting (flex piping is great for this). Make sure that the In and Out ports are pointing the right direction. Use adapters on ports if your pipe size does not fit. Apply Teflon tape on all threaded ends for sealing which helps to prevent leaks. Be careful not to over tighten any plastic fittings to prevent cracks. If you make use of push fittings, no soldering is required. If you prefer to solder, make sure that pipe ends are clean and keep the heat away from any plastic.
  10. If your whole house filter comes with housings, rinse their insides with warm water to remove any manufacturing debris prior to installing. Grease O-rings and make sure that they sit tight.
  11. Turn the water back on.
  12. Open all valves except for the bypass.
  13. Check for leaks. Tighten fittings and filter housings if need be.
  14. Older houses often use their water pipes for grounding of the electrical system. If this is the case in your home, add a jumper cable (copper wire) from one side of the filter to the other to ensure that the ground stays intact. You can do this with the help of grounding clamps.
  15. Flush the entire system for several minutes. This will remove any air, old water as well as installation debris.
  16. Follow manufacturer instructions to properly activate any filtration media.
  17. Close all outlets after the pressure has been restored. Done!

FYI: During normal operation the bypass valve stays closed. Whenever the system requires servicing, close both regular valves and open the bypass.


If your manual lacks important details make sure to check out some of the resources that can be found online (such as this website). How about the following installation video?

Time to Get Started

As you have seen, installing a whole home filter DIY-style is not too difficult at all. Just double-check that you have all the necessary tools and components before you start and follow the manufacturer instructions precisely. When in doubt, contact the customer service and search for additional help online. Then you will have your new whole house filtration system set up in no time!

Want more DIY? How about making your own DIY whole house water filter?

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If you have any questions or thoughts about your whole house water filter installation, please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald has been with BOS since the very beginning. She is head of content creation and has fully immersed herself into the home water treatment industry only to become an expert herself. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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Leave a Comment:

Taylor Hansen says August 6, 2020

Thanks for mentioning having the filter system installed should be by the main shut-off valve. My wife and I are building our dream home and I want to install a whole house water filter system as a part of it. I’ll have to find a company that can install it to our new home so it’s ready when it’s built.

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