Reverse Osmosis Faucet Leaking? Here Is How to Fix It!

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Reverse osmosis systems are unparalleled in their ability to remove contaminants from water, but like any filter system, they aren’t bulletproof.

Over time they can develop leaks that require troubleshooting and repairs.

Let’s take a look at some of the common issues that could be causing your reverse osmosis faucet to leak, and what you can do about it.

Key Takeaways

  • Two faucet types are sold with reverse osmosis systems: air gap faucets, and non-air gap faucets. If they are leaking, the troubleshooting process will differ depending on the type of faucet you’re dealing with.
  • Air gap faucets have a small hole in the faucet fixture that is designed to leak in case of a blockage somewhere in the drain system. To solve the leak, you’ll need to locate the blockage and remove it.
  • Non-air gap faucets generally leak if the faucet is not installed correctly, if the rubber gasket is damaged or misplaced, or if the tubing connection is loose.

Troubleshooting: How to Fix a Leaking Reverse Osmosis Faucet

When it comes to fixing a leaky reverse osmosis faucet, the first thing you’ll want to do is determine what type of faucet you’re dealing with.

Reverse osmosis systems can have two common faucet types: air gap faucets, and regular non-air gap faucets.

You can identify which type you’re dealing with by examining the faucet fixture for a small hole (the air gap) near the faucet base. Another way to determine which type you have is by looking underneath the faucet at the tubing connections. One tubing connection means you have a regular faucet, while three tubing connections mean you’re dealing with an air gap faucet.

The troubleshooting process will differ based on which faucet type you’re dealing with, so it’s important to identify the faucet type right off the bat.

young girl opening reverse osmosis faucet

Why Is My Reverse Osmosis Faucet Leaking? + Fixes

Assuming you’re dealing with a leaky non-air gap faucet, the troubleshooting process will be more straightforward.

If the faucet is leaking from the base, then you’ll want to remove the faucet from the sink and examine the condition of the rubber gasket and tubing connection.

Before you do anything make sure to shut off the cold-water supply to the RO system. There should be a shutoff valve under the sink that will turn off the entire cold-water supply. Also close the RO tank valve.

Next, open the faucet to flush out as much of the remaining water as possible.

Now you can loosen the faucet fixture and remove the entire unit from the sink. The exact procedure to do this will differ depending on the faucet design, but generally, there will be a mounting brace that must be loosened to gain access to the faucet underside.

When the faucet is loosened, pull it upward and examine the condition of the rubber gasket around the faucet base. If the gasket is out of place or damaged then reposition it or replace it.

Take a look at the tubing connection. If the tubing connection is loose, then reconnect it and ensure it’s not leaking anymore.

Leaky Air Gap RO Faucets

When it comes to leaky air gap faucets, there are more potential causes to consider. Air gap faucets are designed to send water back up to the air gap hole when there is a blockage in the drain line or sink, so you’ll need to perform a bit more troubleshooting to find the source of the leak.

How Does an Air Gap RO Faucet Work?

An air gap RO faucet is a faucet with built-in backflow protection designed to prevent damage to the filters and RO membrane. These faucets are commonly sold with RO systems and are required by plumbing codes in some municipalities.

Air gap faucets have three tubing connections instead of the one found on regular reverse osmosis faucets.

  • One connection runs from the last post-filter to the faucet, carrying filtered drinking water.
  • Another connection comes from the RO membrane housing. It carries wastewater generated by the system and passes it by the air gap in the faucet.
  • Finally, after the wastewater passes by the air gap it flows down the drain line to the drain saddle and out through your sink’s drain pipe.

Issues That Might Be Causing an Air Gap Leak and How to Resolve Them

A common source of leaking is a blockage in the drain line. This can happen when a large piece of debris becomes lodged in the line – causing water to back up and flow out of the air gap.

If you suspect a clogged drain line is the source of your leak, then disconnect the drain line from both the drain saddle and the barb on the faucet base. Then, clear out the blockage using a pipe cleaner and reconnect the drain line.

Another possibility is that the drain saddle mounted to the drain pipe is out of position. This can pinch the drain line and cause water to flow backward and out of the air gap.

To fix this, you’ll need to realign the drain saddle with the hole in the drain pipe and fasten it tight.

A kink or dip in the drain line is another possible source of an air gap leak. If the drain line is longer than necessary, it can develop kinks in the line that cut off the water flow and send water back to the air gap. A dip in the line can cause a similar issue, with pressure buildup sending water back up to the faucet.

The solution to these issues is fairly straightforward – you’ll need to straighten out the drain line and remove any kinks. If the line is too long and has a dip in it, then you’ll to shorten it by cutting off the excess and then reinstalling it.

Lastly, an improper installation of the RO system can lead to a leaky air gap faucet. The most common issue here is an improperly installed drain saddle.

Drain saddles should be installed above the P-trap and well away from the dishwasher or garbage disposal drain hookup. A drain saddle installed too close to one of these hookups can clog up from the dishwasher or garbage disposal debris.

To fix this issue you’ll need to remove the drain saddle and reinstall it in a better location. This will also require replacing the section of drain pipe where the saddle was installed previously.

plumber installing reverse osmosis system under sink

How to Prevent Your RO Faucet from Leaking Water Again

When it comes to air gap faucets some degree of leaking is not the worst thing in the world. It’s an indication that the system is working as intended and wastewater is being prevented from damaging the reverse osmosis membrane.

To minimize the chances of an air gap faucet leaking you’ll want to ensure the drain saddle is installed in the correct location, the connections are tight, there is no blockage in the drain, and there are no kinks or dips in the drain line.

Leaking from a non-air gap faucet is a more serious issue, as these faucets aren’t designed to leak. To prevent this from happening again, you’ll want to ensure the faucet is correctly installed, the rubber gaskets are intact and positioned correctly, and the tubing connection is tight and not leaking.

If you have any questions about your RO faucet leaking please don’t hesitate to leave a comment below!

About the Author Alexandra Uta

Alex is a content writer with an affinity for research and a methodical attention to detail. Since 2020, she has fully immersed herself into the home water treatment industry only to become an expert herself. Alex has been using water filters and similar products for years which has gained her lots of hands-on experience.
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