Air gap reverse osmosis faucets may gurgle constantly for different reasons. It could be because of air bubbles inside the system, siphoning, or an oversized membrane.
Air can be released out of the system by tilting it while opening the RO faucet.
Siphoning can be prevented by maintaining a straight drain line from the air gap faucet to the drain saddle.
An oversized reverse osmosis membrane needs to be replaced.
It can be perfectly normal for an air gap RO faucet to gurgle if you’re running it for the first time or while the storage tank is refilling.
Why Does My Reverse Osmosis Faucet Gurgle Constantly?
First of all, only air gap reverse osmosis faucets may gurgle; “regular” faucets won’t.
With that said, there are three possible reasons for why your reverse osmosis faucet gurgles constantly.
1. Air Bubbles Inside the System
Air bubbles trapped within your reverse osmosis system can create a gurgling noise. Usually, air finds its way into RO systems during maintenance activities (like when you’re replacing the filters).
When air bubbles accumulate, the result can be a gurgling noise in your reverse osmosis faucet. You can avoid trapping bubbles in the faucet by filling the housings with water when replacing filters.
How to Get Air Bubbles Out of Your RO System
If you already have air bubbles trapped in your RO system, here’s what to do:
Close the tank valve.
Tilt the entire system module to around 45° so only one filter stage housing touches the floor.
While the system is titled, turn on the air gap faucet and let the water flow for a minute.
Wait for about 30 seconds.
Repeat 3 to 4 times.
2. Siphoning
A drain tube connects an air gap faucet to the sink drain pipe. If this drain tube bends lower than the connection points, it acts like a siphon to move water dripping from one end to the other. The movement of trickling water through the tube in a “siphoned” position causes a gurgling noise.
What to Do to Resolve the Issue
To stop gurgles caused by siphoning, adjust the length of the drain tube so that it doesn’t sag lower than the connection points. If the water runs straight from one end of the tube to the other, there will be no gurgling noises.
If your RO membrane is larger than necessary, the membrane will send more water down the drain during purification. Most RO drains cannot control extensive water flow without gurgling.
The Solution
The obvious solution is to use a smaller membrane that suits your water usage. If your faucet drain only gets what it can handle, there will be no gurgling.
Gurgling Noises That Are Perfectly Normal
With air gap RO faucets, some gurgling noises are perfectly normal and do not need fixing.
For example, when you use a reverse osmosis system for the first time, it’s common to hear a lot of noise from the air gap or drain line. The air removed from the system causes the noise.
The movement of the wastewater from the RO membrane to the drain causes another normal gurgling noise. This should only be heard when the storage tank refills, though.
If you have any thoughts about the question, why does my reverse osmosis faucet gurgle constantly, 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.
Learn more about Gene and the rest of the BOS Team.
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Leave a Comment:
Darold Wolff says
June 23, 2023
Our RO system is about two years old and all filters were changed about two months ago. Recently we have noticed increasing gurgling sounds through much of the day but have not heard any sounds in the morning when we first enter the kitchen. How can these rather annoying sounds be eliminated?
