Why Does My Reverse Osmosis System Make Gurgling Noise? + Fixes
Written by: Gene Fitzgerald // Last Updated: Jun 1, 2023
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Reverse osmosis systems generally produce some strange sound effects from time to time.
But if these sounds become too persistent and loud, this could indicate an underlying issue.
For example, one of the most common symptoms of a reverse osmosis system not functioning properly is unusual gurgling noise. Let’s elaborate!
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Key Takeaways
You should not be surprised to hear some gurgling noise from your reverse osmosis system. However, overly loud or ongoing gurgling usually indicates a problem.
Issues that can cause excessive gurgling noise include:
- A misaligned drain saddle – realign
- Excessive feed water pressure – adjust
- An oversized RO membrane – downsize
- A defective flow restrictor – replace
- Air trapped inside the filter system – release
- A drain line that’s too long causing siphoning – shorten
Normal vs Abnormal Reverse Osmosis Gurgling Sound
If you’ve just purchased your reverse osmosis system recently, you might notice a strange gurgling or dripping noise coming out of it. This is completely normal and will subside over time. It’s just air being removed from the system.
Another reason for normal gurgling noise is when the system is producing filtered water and sends wastewater down the drain doing so.
However, if the sound is more persistent or particularly loud, this could indicate that there is indeed something wrong.
Why Does My Reverse Osmosis System Make a Gurgling Noise and How to Fix It?
There are several common causes for unusual gurgling noise from reverse osmosis systems. Identifying the problem comes down to going through that list and eliminating potential causes one by one. Here are the things you should consider.
Misaligned Drain Saddle/Pipe
If your vertical drainpipe is not hooked up correctly and is crooked, this could cause water to get ejected from the RO system dripping down directly into the P-trap. This can make gurgling and dripping noises. The fix for this is to simply straighten the drainpipe. This way, the RO waste water runs down the side of the drainpipe all nice and quiet.
Feed Water Pressure Too High
You need to be careful about the pressure of your plumbing if you’re using a reverse osmosis system. Generally, you will need to provide a high level of pressure to ensure that the system operates correctly. However, it’s possible to make the pressure too high and prevent the system from functioning properly. In this case you might have to control your plumbing pressure with a dedicated pressure regulator.
Excessive feed water pressure could cause your RO system to send high amounts of wastewater down the drain causing gurgling.
Oversized RO Membrane
An oversized reverse osmosis membrane will send more water down the drain than it should. This can cause gurgling as well. Make sure that you’re getting a membrane that’s adequately sized for your current situation.
A Defective Flow Restrictor
If the flow restrictor on your reverse osmosis system is not functioning correctly, this could also lead to unusual gurgling noise and other strange effects. In this case you will have to replace the flow restrictor entirely. Don’t attempt to repair it as this is usually a more complex job than you would be able to handle.
A Gurgling RO Faucet
Air gap faucets are particularly prone to gurgling.
Air Bubbles Inside the System
If air is trapped within the filter system, this will cause some gurgling from the reverse osmosis faucet. Your system might trap air for various reasons, and you need to investigate the root cause of the problem so that you’ll know how to fix it.
For now, open the faucet and tilt the system 45° to get rid of any trapped air.
Further Reading:
Siphoning
If the tubing that connects your air gap faucet to the drain is too long, it could sag in some places, which can result in the creation of air pockets. The only way to fix this is to make sure that the tube is as short and straight as possible, so that air doesn’t have any chance to get trapped.
RO System Gurgles Constantly?
Some minor amount of gurgling is to be expected when operating a reverse osmosis system. However, if the problem persists, you might need to investigate the actual cause. In pretty much all cases, constant gurgling is related to draining. If your system is draining too often, you have to figure out what’s wrong and address the issue at its source.
Here is an overview for why a reverse osmosis systems keeps draining and how to fix it:
- Low feed water pressure – increase
- Clogged reverse osmosis membrane – replace
- Underpressurized storage tank – repressurize
- Ruptured tank bladder – replace tank
- Broken ASO or check valve – replace
- Broken flow restrictor – replace
- Reverse osmosis system improperly installed – reinstall
If you have any questions about reverse osmosis system gurgling please don’t hesitate to leave a comment below!
About the Author Gene Fitzgerald
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