How to Install a Whole House Reverse Osmosis for Well Water

You may have well water in your home, and you might want to have exceptional pure water quality, not just for drinking but throughout your home. Some well water, being groundwater, can be compromised by numerous difficult contaminants that Reverse Osmosis (RO) can be the only feasible option to have clean water for your house.

Reverse osmosis purifies the water and separates chemicals, pesticides, pharmaceuticals, and dissolved solids from the purified-water. It can remove contaminants like arsenic, boron, chromium, copper, mercury, silver, lead, sodium, and nitrates. Some of these are toxic, and it would be wise to eliminate them from every faucet in your house.

Installing this system needs careful planning and research understanding of your water’s chemistry.

Things to Consider:

1. Water Test

Conducting a detailed water test will reveal the contaminants present in your water. You will know the pretreatment you need to do with it when you know the contaminants present and their level.

Gather some samples from your water source and have it tested in certified labs or water test labs. These labs use the EPA standard and measure the presence of contaminants in parts-per-million.

2. Water Pretreatment

You need to have your water undergo pretreatment if your water is of poor quality. Your RO membrane needs protection from particular water contaminants. Doing this will prolong the lifespan of the RO membrane and maximize the RO system over-all performance. That is why you must have your water tested first and find out its composition. Executing this will give you an idea of the best way to pre-treat it.

You may be required to have a water softener if you have hard water. Hard water contains hard minerals like calcium and magnesium that can damage your RO membrane and might lead to requiring frequent replacement of the RO membrane. A water softener will eliminate these hard minerals and preserve the RO membrane’s efficiency and longevity.

RO systems usually require both sediment and carbon prefilters. Sediment filter filters out solids away from the water. RO membrane is capable of doing this job as well, but it could cause harm over time because it may lead to obstruction. The other prefilter stated is used to rid of Chlorine.

3. Figure Out the RO system size needed for the Whole House

You need to find out the daily water usage of your house to have an idea of what kind of RO system would best fit to support it. You need to have a storage tank that can provide water to the whole house even when the water is running. A water specialist can aid you in choosing the right measurement of the RO system and tank that will be able to sustain your whole household water needs.

4. Water Post-treatment

The water produced from a reverse osmotic is mildly acidic, and acidic water is corrosive and can erode copper plumbing and cause pinhole leaks to appear. That is why it is a good idea to have a pH adjuster to adjust the water’s pH before it enters your house.

Keep in mind that reverse osmosis operates by removing disintegrated contaminants, but it has no application for microbial elimination. Ultraviolet (UV) light is the one you need to remove living organisms and viruses. It is usually the last part of filtration processes.

5. Figure Out Where to Install Your RO System

Install your RO system in a place where water enters your house. These will prevent contaminated water from going inside.

A Whole House RO system is massive and takes up a lot of space. Keep in mind that a RO system needs to be indoors and be kept in a room where the temperature will not freeze your water nor your equipment. You also want to make sure that there is enough area for your pretreatment, post-treatment equipment, and your tank.

Choose an area that could easily access your key water source. Also, make sure that the location allows for clean drainage of wastewater.

6. Waste/ Wastewater

The RO system purifies water and produces wastewater as a byproduct. The RO membrane separates the purified-water called permeate from the solution-filled-with-contaminants called brine. The brine needs a specific drain that will allow for its easy removal from the system and the house.

Steps for RO System Installation

Carry out all the plumbing by following the state and local plumbing codes, so remember to check them. Also, keep in mind that some municipalities require installation by a licensed plumber.

RO systems usually have all the tubing and items you need to have it installed. You can hire a plumber to do a professional installation for you. Most of the plumbers take just twenty minutes to read installation instructions and an hour or two to do the installation.

If you want to do the installation yourself, here are some materials you need:

  • Adjustable wrenches
  • Buckets (to catch the remaining water in the main supply after shut off)
  • Drill
  • Drill bits(assorted)
  • Tubing Cutter
  • Whole house RO system

Make sure that you shut off your home water supply first before proceeding to the installation. Read the instructions and conditions in your RO system manual before you begin the installation process and double-check that you have all the components listed in your manual. Doing this will avoid common issues or troubles from occurring.

Step 1:

Choose a convenient location near the main shutoff. There should be enough room under the filter system that you will not have any trouble when you need to have it changed.

Step 2:

Mark the pipe and cut it, then place a new shut off valve. An adapter may sometimes be needed to connect your pipe size and your filters.

Step 3:

Make sure that it will not be difficult for you to reach your filter when you need to have it changed when you build your RO System. Once you are satisfied, you can mark it for cutting.

Step 4:

After cutting the pipe, you can now install your RO system. Place your compression rings and nuts to secure the connection, then turn back on your water system.
Check if there are any leaks and tighten the connections if there is a need.

(You will need to add a jumper cable if you already have a ground wire in your water supply pipe to restore this feature)

Consult professional help and ask questions if you ever get confused during the installation process.


Reverse osmosis is a cost-effective method for purification, but it takes careful planning and diligent maintenance. If you want to have one installed to support your whole house water consumption, make sure that you are committed and have done thorough research.

Do not ever be afraid to ask for professional help when you are unsure of what to do.