So, you’ve decided to add an RO water filter system to your home, because you don’t want to be exposed to those nasty tap water contaminants any longer. You found a great model online that suits your needs and you purchased it a couple of days ago. This morning the system arrived in a big heavy box. Although you haven’t had the time to do the installation, out of mere curiosity you opened the package to take a first glance…
What a shock! You didn’t anticipate that a single system would include that many different parts. There is a tank, different filters, a membrane, an extra faucet, tubing of different colors, and a couple of smaller connectors and valves.
Now all you can think about is that hopefully you have the expertise to set everything up correctly – after all, you are not a plumber! But considering the costs for hiring a professional that would add to the expenses of the filter system itself, it’s a priority for you to do the installation on your own.
Don’t worry. We’ve got you covered! In this article we will provide you with all the resources you need for a trouble-free installation process.
On this page you will learn:
It’s time to learn how you can hook up your new reverse osmosis under sink system the right way. With a little preparation and the necessary tools, you don’t have to be a professional plumber to set up everything correctly.
Also, every system comes with detailed setup instructions. If that isn’t enough, you can find numerous helpful installation videos from different manufacturers on YouTube.
Before You Start, Carefully Read All Steps and Safety Guidelines in Your System’s Installation Manual. If in Doubt About Your Next Step, Consult the Manufacturer.
Individual steps may vary from product to product and depend on your specific plumbing setup. Therefore, the following installation details are given as a general approach.
Before you even purchase an RO system, it’s a smart idea to make sure that there is enough space under your kitchen sink for the tank and the filter module. So, look up the specifications of your favorite system and perform some measurements.
You also need to make sure that there actually is a cold water line you can draw the feed water from (which, of course, is nearly always the case).
Once the system has been delivered, unbox it and double check that all components fit in their desired location. This way you already know beforehand if you need to make some adjustments to the drain or other pipes before the installation itself can start.
Identify and assemble all necessary tools and components. Having everything you need lined up before you start the installation can save you from a lot of frustration. The following list makes no claim for completeness:
We begin the installation with setting up the RO faucet that will soon provide great tasting, filtered drinking water. Most RO faucets have a connection with a 1/4″ or 3/8″ tubing fitting.
First of all, you have to decide where you want to place the faucet, which is an easy decision, if your sink already has an extra hole for the mounting. If it doesn’t, you have to drill a new hole into the sink or the countertop. Depending on the type of material, you may require a special type of drill bit here.
Gently grind away enough surface material to safely accommodate the 1/4″ drill bit. Now carefully drill the hole and go extra slow when you are about to penetrate any metal (a drop of oil in the hole can work wonders).
When you are done, remove any remaining metal chips that could damage the surface. Place the faucet stem inside the hole and secure it with a nut from the bottom. Then attach the quick connect fitting to the bottom of the faucet and tighten it with a hand wrench.
The next step is to install the drain saddle or drain line adapter to the drain line. The saddle/adapter has to be placed above and as far away as possible from the dishwasher discharge and garbage disposal to protect your RO system from potential contamination and fouling.
Drill a 1/4″ hole into the top or the side of the drain line (never the bottom). Put the drain saddle in place and fix it with bolts. Be careful to not over tighten anything.
In step three, we install the inlet feed valve, which connects the RO system to the cold water line of the existing sink.
First, turn off both the cold and hot water supply. If the valves are inoperable, you have to shut off the whole water supply to your home. Next release the pressure in the water lines by opening the faucet. Then remove the tubing from the cold water valve and install the new feed valve. Make sure to turn the feed valve off.
Attach the cold water tubing back to the new valve and turn the cold and hot water supply back on.
You should place the storage tank within 10 feet of the drinking water faucet to not lose any significant pressure. And don’t forget that a tank can weigh up to 30 pounds when filled up to the top.
By the way: With many systems, the storage tank can also be placed on its side without affecting filtration performance. This comes in handy, if you lack sufficient space under your kitchen sink.
Before putting it in position, it is often advisable to wrap about 5 winds of Teflon or plumber’s tape around the threaded port on top, before attaching the tank valve or tank connector itself. The connector should thread on easily and only needs to be hand tight.
Now it’s time to install the RO module itself using the color coded tubing. Keep in mind that trimmed connections will maximize water flow rate. On the other hand, leaving some extra tubing will come in handy, if the system ever needs to be moved somewhere else.
Apart from this, there may be water residues in the tubes if the system was tested by the manufacturer, so keep a towel at hand to wipe it up.
As with the storage tank, many RO modules can be mounted both vertically and horizontally. When positioning, take into consideration that every once in a while you need to access the module for filter replacements and other maintenance tasks.
Once all the connections are made, place the different filters and the RO membrane into their housings according to the instructions provided. Usually, the first filter will be the sediment filter, followed by carbons filter(s), and lastly the membrane.
To put the membrane in place you have to remove the housing cap and carefully push the cylinder into the socket until completely in. Then put the housing cap back on.
Finally it’s time to start the system! Here is how:
It is recommended to flush a new RO system 2-3 times prior to use. Once you’ve done that, the installation is completed and your water is ready for drinking.
A large proportion of customers choose to install their RO system themselves. However, an even larger part prefers to turn to an expert, because these people are worried about not having the right tools and knowledge to complete the task.
If you, too, are in doubt about your manual skills, we recommend you to call a local plumber to do the installation for you.
How much the installation of an RO system costs, depends first and foremost on what kind of system you want to have installed. We distinguish between:
If you don’t already have a plumber in mind whom you trust, checking out local reviews online is a great starting point. Popular sites you can use are:
Furthermore, it is likely that you can save a lot of cash, if you talk to more than one plumber and let them know that you already have purchased a system, but need help with the installation. Ask for their expertise, references, and a cost estimate.
If you have any questions or thoughts about how to install an RO system, please don’t hesitate to leave a comment below!