Reverse Osmosis System Leaking? Here’s Why + How to Fix!

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You wake up one day and notice your reverse osmosis system is leaking. What could be the cause? And how do you fix it?

In this article, we’ll discuss what causes reverse osmosis systems to leak and what you can do about it!

We’ll also share tips for preventing leaks in the future, so keep reading to learn all about it!

Key Takeaways

Your reverse osmosis system could be leaking due to:

  • The system’s age – replace if it has exceeded its lifetime
  • Feed water pressure spikes – adjust water pressure or get a pressure regulator
  • Loose tubing or other connections – tighten
  • Improper installation – reinstall
  • A leaking O-ring – clean, lubricate, reposition, or replace
  • Over-tightened filter housing – adjust
  • Cracked filter housing – replace
  • Clogged filter/membrane – replace
  • A damaged storage tank – replace
  • A leaking faucet – fix or replace
  • Overall low-quality product – replace

How to Troubleshoot a Reverse Osmosis System That’s Leaking

If you notice a leak in your reverse osmosis system, it’s time to troubleshoot.

RO systems consist of many different parts that work together to filter your water. A problem with any of these parts could result in a leak. So, what parts are most likely to cause problems? Where should you look?

Finding the Source of the Leak

Take a flashlight with you and follow the trail of water to find the source of the leak. If you don’t find it right away, carefully inspect the most likely places for a leak to start. Places to inspect include:

  • Storage tank
  • RO faucet
  • Tubing connections
  • Filter/membrane housings

Why Your RO System Is Leaking + How to Fix It

So, why is your reverse osmosis system leaking?

Well, your RO system could be leaking for different reasons; let’s talk about these and some easy fixes.

plumber installing reverse osmosis system under sink

System Age

Older reverse osmosis systems are more likely to develop leaks than newer ones. The average RO system lasts 8-10 years. The leaks can signify that it’s time to let your RO system go and get a new one.

How do you know age is the problem with your system? You know your system is old when:

  • You notice more frequent issues and damages in your system than normal.
  • The system sounds a lot louder than usual.
  • The water tastes bad even after you change the filters.
  • You’ve been using your system for 10+ years.

The only solution to this problem is to replace the entire unit. If your system is still fairly new, pay attention to how much time it has left and replace it when it hits the 10-year mark (provided it’s causing problems).

Feed Water Pressure Spikes

RO systems are highly dependent on water pressure; they remove contaminants from water using high pressure. However, a sudden spike in your feed water pressure could damage your filters or their housings, tubing, connectors, and even the air bladder inside the storage tank. Too high or unstable pressure could also cause membrane shell rupture.

All of these system damages come with one consequence — leaks in the RO system.

Solutions to feed water pressure spikes:

  • Adjust your water pressure if possible.
  • Get a new pressure regulator.
  • Replace any damaged components of your RO system.
  • With an under sink RO system, you could install a separate pressure valve before the system.

Loose Tubing or Other Connection (Improper Installation)

Reverse osmosis systems go through endless wear and tear, which causes connections to go loose. When tubing is loose, leaks begin to spring up in the system.

Another cause of leaks in an RO system is accidental bumping. This is very common in under sink RO systems. Because they’re set in cabinets, it’s easy to accidentally bump the system or tug a line when accessing that cabinet. Bumping into the system and tugging lines can cause connections to become loose, which often results in leakage.

Besides loose tubing, other loose connections can also cause your system to leak. Improper installation of filter housings or an incompatible adapter means that all the parts of your system will be unable to work as they should.

Solution: Tighten all connections. Push tubing all the way into their quick-connect fittings. Check adapters and filter housings. If the leaking persists after tightening connections, you may need to uninstall and reinstall all the components.

A Leaking O-Ring

An O-ring is a small (typically black) rubber ring that is used to provide a tight seal between interlocking components. O-rings are a vital part of any RO system because they prevent water leakage from the filter housings and ensure water actually flows through the filter cartridges.

Most reverse osmosis filter housing leaks arise from problems with the O-ring. Small cracks or even dirt and dust can cause problems in the O-ring and result in leaks. Your O-ring could also cause leaks if it’s twisted or pushed out of place.

Leaking O-rings are more than a mere inconvenience – the water leakage can contaminate the water or even damage the entire system. It’s crucial to check your O-rings for any signs of cracks, damages, or wear and replace them when necessary.

If an O-ring is leaking but undamaged, you can simply push it back in place so it fits securely. But if your O-ring is damaged, you have to replace it.

In summary, an O-ring will leak if it’s broken, not in place, faulty, or dirty. Cleaning and lubricating O-rings with food-grade silicone also helps.

Over-Tightened Filter Housing

You may think a tight filter housing would prevent a leak, but in reality, many leaks are caused by over-tightened filter housings. Manufacturer manuals clearly state that you should avoid over-tightening your filter housing.

When you over-tighten your filter housing, hairline cracks can form in the sump or threads, causing leaks. Over-tightening could also cause the O-ring to flatten, pushing it from its normal position and causing leaks. It could also crush the O-ring.

A clear sign that your filter housing is over-tightened is little drops of water flowing from the top of the filter housing. If your filter housing is already leaking from being over-tightened, you must replace it. Depending on its current state, you’ll also need to replace or reposition the O-ring.

Cracked Filter Housing

Over-tightening your filter housing doesn’t stop leaks. Instead, it causes cracks to run across said housing. There’s no fixing a cracked filter housing. The only solution is to replace it.

Here’s how you can replace a cracked filter housing:

  1. Turn off the water inlet and storage tank valve.
  2. Drain all remaining water.
  3. Unscrew the cracked filter housing and screw on a new one.

Clogged Filter/Membrane

RO systems work around the clock. Eventually, filters and membranes get clogged and begin to restrict the flow of water. When the pressure gets too high, leaks may start to appear. Fortunately, fixing this is easy – all you need to do is replace your filters.

If you use hard water, you’ll need to replace your filters more often, especially the RO membrane. You could also install a water softener at the point of entry to your house to soften your water.

blue reverse osmosis membrane

A Damaged Water Storage Tank

Your tank could be damaged if the air bladder inside is torn, if there’s a hole in the tank, or if one of the valves is malfunctioning. The solution is to find and replace any broken parts. If this isn’t possible, buy a new tank.

A Leaking Faucet

A leaking RO faucet is never fun. Your faucet could leak due to loose connections, damaged O-rings, clogged aerators, high water pressure, or a faulty faucet valve. Inspecting the faucet and connections carefully can help you determine the exact cause of the leak.

Leak at Faucet Stem

The faucet stem is the part of the faucet that controls the flow of water. It’s located inside the faucet body, directly under the handle. The faucet stem has a rubber O-ring near the base that forms a watertight seal when the faucet is closed. If this O-ring is damaged, the stem develops a leak.

The faucet stem could also leak if the stem itself is damaged, if the water pressure is too high, and if there’s sediment buildup around it.

Leaking Air Gap

The air gap is designed to prevent wastewater backflow into the RO system. A leak in the air gap could be due to improper installation, high pressure, or a clogged or damaged drain line.

Low-Quality Product

Low-quality RO systems are bound to have issues with leaks. For example, low-quality filters will clog faster and cause more leaks. Only buy your reverse osmosis products from reputable brands to avoid this unpleasant scenario.

Tips for Preventing RO Water Filter Leakage

Here’s how you can prevent future RO Leaks:

High-Quality Components

Procuring high-quality components is important if you want to prevent future leaks. Only get top-grade replacements when you change your filter cartridges.

Timely Filter Replacements

Replacing the filters and membrane in your reverse osmosis system on time will save you a lot of trouble. Check the manufacturer’s specifications to determine when your filter elements need to be replaced. This lowers the chances of getting clogs.

Being Mindful When Replacing Filters

You need to be careful when replacing filters. It’s tempting to want to over-tighten your filter housings, but don’t do that. Only tighten a filter housing with your bare hands (not too forcefully) or carefully with the plastic wrench that comes with your system.

System Inspections and Cleaning

Reverse osmosis systems experience a lot of trouble when not properly cleaned or maintained. You should clean yours at least twice a year with regular dishwater and a sponge (no complex routine here). Removing the dirt and sediment buildup in the system helps to prevent clogs.

Another thing to pay attention to is your O-rings; they need to be cleaned and lubricated with food-grade silicone. Do not use petroleum jelly.

Remember to check the storage tank for leaks and replace filters if your water tastes weird.

If you have any thoughts about the question, why is my RO system leaking, 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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