RO Water filter noise

[jjw13]

Hello,
My under sink RO water filter system was working fine and quietly, until recently. I've contacted the manufacturer several times, and under their suggestion replaced the pre-filters and the flow restrictor. The gurgling noise continues to come from the air gap on the back of the faucet - and it is loud. The tubes are all cut to the proper length to ensure that its draining properly, and the system does stop running when the tank is full. But, whenever I run the faucet and the tank is empty, the sound returns. The only way I can get the sound to stop is to disconnect the system's drain tube and let it run into a bowl, but once I reconnect it to the sink drain it returns. (The RO water system drain tube is connected to the pipe that runs across from the 2nd sink to the main drain, to prevent that dripping noise.) Any advice on what might be causing the sound? All help is appreciated.

[Simba Sharma]

The only way to get rid off this problem is by calling the company guy to fix it.
They will be able to solve the problem better .As I could see that you have taken all the steps to stop the noise.

[pawaterguy]

Air gap faucets are a pain in the arse for noise. They clog up and make for service trouble. Drop some chlorine down the air gap hole in the faucet to try to clean the line out. If all else fails...take the drain line tube from the RO and put it directly into the drain line...eliminating the air gap. It will not meet code...but, it will work and it will work quietly. So long as you drill and tap the drain line correctly. If the line goes through the wall tap it on top of the drain line...if it goes through the floor tap into it in the vertical line going to the floor. As long as you're not clogging up on the drain...you're golden. The air gap is there to prevent the possibility of something backing up into the RO and contaminating it in the event of a clog in the drain line.