Reverse Osmosis Faucet Leaking at Base? Here’s What to Do!

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So your reverse osmosis faucet leaks at the base, out of the air gap, and dribbles water all over your countertop. Annoying!

Thankfully, you can do a few things to assess the issue and, in most cases, fix it yourself.

Here’s our handy how-to for a leaky RO faucet base.

Key Takeaways

Here are the potential causes for a reverse osmosis faucet leaking at its base and how to fix them:

  • A clogged drain line – Detach the drain tube and clean it out manually with a pipe cleaner.
  • Kink/dip in drain line – Remove, straighten, or replace the kinked drain line.
  • Improperly installed reverse osmosis system – Check all the different components, especially the drain saddle.
  • A loose connection – Check all your connections and tighten if need be.
  • An old system – Time to replace your RO system entirely.
  • Feed water pressure spikes or pressure too high – Get a pressure regulator.

How to Fix a Reverse Osmosis Faucet Leaking at Its Base

There are several reasons why an air gap RO faucet could be leaking at its base.

Debris building up in the drain line is often the primary cause. Improper installation or loose connections could also be the culprit, among other things. Either way, you’ll want to fix it up ASAP to make sure you aren’t going to damage your RO system or countertop.

Further down, we will go through each possible reason for why an RO faucet base might leak and how to fix them.

young girl opening reverse osmosis faucet

How Air Gap RO Faucets Work

An air gap RO faucet is designed to prevent contaminated water from flowing back down into your filter system and damaging the reverse osmosis membrane.

The wastewater produced from the filtration process travels up a drain tube, past the air gap, and then drops down to be disposed of with the household wastewater.

The air gap is a little pocket of air, and once water moves past it, it can’t travel back up. As such, air gaps are used as backflow prevention and are often required by local plumbing codes.

A Clogged Drain Line

This is one of the main reasons for a faucet base leak, so it should be the first thing you check. When dealing with water that has high levels of sediment, blockages can happen even more often.

Essentially, there’s dirt somewhere along the drain line that causes a partial or full clog. The drain water cannot go anywhere except flow out the faucet base (the air gap hole).

Other areas that can get clogged include the drain saddle, and when the drain saddle clamp has rotated from the hole drilled in your sink drain pipe.

How to Fix

There are a couple of ways you can do this. First is to seal the air gap hole with your finger, and then blow down the tubing connecting the reverse osmosis system to the air gap. See if the air flows freely or if it dislodges any blockages.

If the blockage cannot be dislodged, then you’ll need to detach the drain tube and clean it out manually with a pipe cleaner. Reconnect and check if it’s fixed the leak.

Kink/Dip in Drain Line

Drain line tubing with kinks or dips in it can restrict the flow of water to the drain saddle, causing leaks from the air gap hole.

How to Fix

Turn off the RO system and remove the kinked drain line. Straighten it out, then reattach and test it out. If you can’t straighten it, the drain line may need replacing.

Improperly Installed Reverse Osmosis System

Sometimes even small mistakes during the system installation can cause issues with your RO’s performance. Some of the main problems for an improperly installed reverse osmosis system are:

  • Drain saddle not far enough away from the disposal (more likelihood of debris entering the tubing)
  • The drain saddle is rotating around the drilled hole from the air gap faucet installation.

How to Fix

For this issue, the best thing to do is to remove and reinstall the drain saddle again, being doubly sure not to make any mistakes when installing.

Also check the faucet itself. If this is not possible, a new air gap faucet may be needed.

plumber installing reverse osmosis system under sink

A Loose Connection

Loosely connected components of the RO system can also cause issues. This can happen during installation, when maintaining and changing the filtration components, and over time, as things generally get a little loose due to the pressure used in an RO system.

How to Fix

Check all your connections and tighten them. Check that the drain saddle is appropriately aligned and not loose, and realign if needed. If tightening doesn’t work, you may need to uninstall and reinstall the loose components altogether.

An Old System

While an RO system can last a good ten years, it will eventually wear out and need replacing. This can lead to it leaking more frequently, or leaking and not being able to be fixed. If your system is experiencing more issues than average, or if it is getting louder, or the water is starting to taste odd, then they are signs your system might be due for a replacement.

How to Fix

Time for a new system!

Feed Water Pressure Spikes or Pressure Too High

Pressure spikes or high internal water pressure in the filter system can also cause leaks and damage the components of the faucet.

How to Fix

You will need to replace the RO faucet if it is not fixable and buy a pressure regulator to ensure it does not happen again.

Preventing Future Leaks

  • Clean your drain line annually or whenever you do your filter replacements. Prevention of a clogged drain is better than a cure.
  • Don’t rinse chunks of food and debris down the sink drain.
  • Use an all-natural drain cleaner every so often to break down any waste that may be stuck in your drain.
  • Ensure your air gap faucet is installed correctly to begin with.
  • Ensure the drain saddle is installed far away from your disposal.
  • Try not to bump the system under your sink, as this can loosen the drain saddle over time.
  • Double-check your system is aligned and connected correctly whenever you replace the filters.

If you have any questions about a reverse osmosis faucet leaking at the base please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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