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How To Fix Reverse Osmosis Leaking From Air Gap – 4 DIY Fix

Reverse Osmosis Leaking From Air Gap


The reverse osmosis system is the common under-counter and countertop home appliance. It removes harmful chemicals and biological entities, hence ensuring drinking water safety. But what if the reverse osmosis air gap leaks occasionally? Isn’t it annoying?

If the RO system leaks from the air gap, it means the drain lines are blocked or problematic, and the saddle connection is faulty. Don’t panic; you can fix it by opening and cleaning the drain tube and saddle until the drain system is free to flow. Carefully reassemble the drain saddle and fix the drain tubing in its proper position.

In this blog, we will describe how air gaps in the RO system work and why it gets blocked occasionally. Plus, we will explain the methods in detail to fix air gap leaks and how to prevent them from leaking in the future. Stay tuned

How Does an Air Gap in the RO System Work?

The air gap is the physical space designed in the reverse osmosis faucet. It prevents drained water from flowing back into the system. Occasionally, when the drainage system gets clogged, it restricts the flow toward the disposal. In this event, the air gap starts pouring the wastewater and prevents backflow into the system.

Why is Water Coming Out of My Air Gap?

Why is water coming out of my Air Gap

If your reverse osmosis system leaks from the air gap, it is a sign that something is problematic with the drainage system. It could be due to the clog formation in the drain tube, any blockage in the drain saddle, or debris accumulation narrowing down the drain pipe near the disposal.

Here, I will discuss the reasons in detail that can cause the water to pour out of the air gap.

1. Blockage or Clog Formation: 

Suppose the feed water contains excess minerals, dirt, and contaminants. In that case, there is a high chance of clog formation in the drainage system. The feed water, when filtered, the wastewater contains high levels of contaminants and minerals. When it flows in the drain lines, it accumulates into its tubing and saddle clamps. So, it restricts water flow towards disposal and causes air gap leaking.

2. Drain Line Issues: 

Tempered drain lines and damaged RO faucet stems can be the cause of air gap leaks. It restricts wastewater in the drain toward disposal and starts the air gap pouring.

3. High Water Pressure: 

The RO tank pressure should be between 7 to 8 PSI if the feed water pressure exceeds, which in turn increases the pressure in the tank and drain system. There is only gravity force that causes drain water out of the disposal. When the wastewater pressure increases from the RO membrane, it causes water to pour out of the air gap instead of draining all water from the disposal.  

4. Improper Installation: 

The loose or misplaced drain saddle clamp, unorganized drain saddle mounting, bad drain tubing distribution, and improper check valve installation can cause the occasional air gap leak.

Suppose you are experiencing an air gap leaking water. In that case, it’s important to determine the issue promptly. Depending on the cause of the problem, you may need to clean, repair, or replace components of the RO system itself.

How to Fix Reverse Osmosis Faucet Leaking From Air Gap?

How to fix reverse osmosis faucet leaking from air gap

If your reverse osmosis system leaks from the air gap, this could be due to any blockage in the drainage system, tempered draining tubes, unorganized drain saddle mounting, and false plumbing. To fix the RO air gap leakage, disconnect the drain tube and saddle, remove the obstruction causing the blockage, clean it, and reconnect it properly to ensure free wastewater flow.

To fix the issue, here is the step-by-step guide to follow along.


Before performing this, make sure you’ve shut off the RO water supply.

1. Disconnect the Drain Line and Drain the Saddle Clamp

Disconnect the Drain Line and Drain the Saddle Clamp
Disconnect the Drain Line and Drain the Saddle Clamp

If the reverse osmosis system leaks from the air gap faucet, the most common reason for this can be the blockage due to clog formation or debris accumulation anywhere in the drainage system. So,

  • Disconnect the drain tube from the drain saddle
  • Disconnect the drain saddle clamp from the drain pipe

2. Clean the Drain Line or Tube

Clean the Drain Line or Tube
Clean the Drain Line or Tube

A plug or clog formation mainly restricts the drain water to flow. It mostly depends on the quality of the source water fed to the RO system. A highly contaminated water source produces more concentrated drain water, which in turn forms clogs and causes blockage in the drainage system. To clean the drain tube

  • Take a small metal wire or rod and a bucket 
  • Swirl it into the drain tube to take out the clog.
  • Repeat this process until the tube becomes clean  
  • Turn on the RO water supply and check if the drain line is clean.
  • Pour the drain water into the bucket until all the blockage comes out.
  • Cross-check the RO faucet air gap if it is not dripping water now.
  • If the air gap stops leaking, it means the drain is cleaned.
  • Shut off the RO water supply and follow the further steps.

3. Clean the Drain Saddle and Pipe

Most of the time, clogs get stuck into the drain pipe and saddle opening. Cleaning the saddle and drain pipe is important to avoid air gaps from occasional leaking. To clean it

  • Take a metal rod, place it into the drilled hole, and drain the pipe
  • Clean the saddle and pipe to ensure free wastewater flow

4. Reconnect the Drain Line and the Saddle

Once you’ve ensured the drain pipe, tube, and saddle are cleaned. Then, it is time to reconnect the setup again. Connect the saddle clamp back and the tubing to its position.

  • Take the drain saddle front plate and place it. Ensuring that the front plate opening is aligned with a drilled hole into the drain pipe
  • Place the drain saddle back plate and tigh it.
  • Take the drain tube and reconnect it with the drain saddle carefully by pushing it into the saddle opening.

How to prevent the Air Gap in the reverse osmosis system from Leaking water?

To prevent the air gap from leaking in the RO system, you must understand the reasons behind this. The air gaps most commonly leak due to debris formation into the drainage system. The clog formation within the drain system restricts the water flow, which makes the air gap leak. 

However, you can’t prevent the RO system from occasional air gap leaks, but you can minimize the frequency. To do this, you can improve the drain system plumbing or use Megamicriobes drain cleaner on a weekly basis.

Below, I will explain the most useful tips to avoid this air gap leak event.

1. Use Drain Cleaner

It is very difficult to prevent air gap leaks, but you can minimize the frequency of this occasional leak. For this purpose, you can use megamicrobes liquid drain cleaner available in the market.

2. Cut the Excess Drain Tubing

Remove or adjust the excess drain line tubing. Do not let the tube down than the drain saddle level. It will also help to minimize the chances of clog formation within the line.

3. Mount the Drain Saddle Properly

Mount the Drain Saddle Properly
Mount the Drain Saddle Properly

If you face air gap leakage frequently, it is best to mount the drain saddle in a horizontal position. Keep the saddle drilled hole aligned with the drain tube to ensure the free drain water flow. Proper drain saddle mounting will also prevent the RO system from making a gurgling noise.

4. Mount Place Drain Saddle Far Away From Disposal

Disposal is responsible for forming the debris and shooting it into the drain saddle, which in turn narrows down the saddle drilled hole. It is wise to keep the drain saddle far away from the disposal.


In this detailed guide, We explained the reasons why is your reverse osmosis system leaking from the air gap. We’ve also provided step-by-step solutions to diagnose and get rid of this annoying issue. Additionally, I’ve provided some permanent fixes to minimize the frequency of occasional RO system air gap leaking.

Suppose you are not tech-savvy or uncomfortable with any plumbing process. In that case, it’s best to seek professional assistance to fix the air gap leak. However, we advise you to reach out to RO system support from the brand you’re using. 

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