Reverse Osmosis Drain Valve - Best Location in Single Drain Sink?

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My sink only has one drain that connects directly to the garbage disposal, and the Reverse Osmosis drain valve installation doesn't have any recommendations for this setup.

Would the circled area (just before the Redi-Vent but after the P-trap) be the best place to install the RO drain valve, extending the pipe a bit if necessary?

Or is there a better option (e.g. install new connector with valve coming out of garbage disposal just before P-trap)?

Thanks in advance for sharing any thoughts!
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Tuttles Revenge

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Bit late on answering this but because I'm researching this very same for a future clients project I thought I would put this to bed.

The reverse osmosis system should have some form of Air Gap built into the faucet that is designed to prevent your clean water tubing from being contaminated from the gunk in the drain. This Kingston Brass KSAG819DL faucet has the airgap built into it. The tube that drains the system should then attach to the drain of your sink. This can be done with a slip joint tee on a vertical section before the trap or on a horizontal section if you have a double bay sink.

Below is the fitting we will be installing in our project. But some RO systems come with a saddle tee that pierces a small hole in the side wall of the drain pipe or on the top of the horizontal pipe.

To directly answer the question of where not to hook up the drain.. not on the vent or any portion after the trap. Those areas are not protected against sewer gases coming back up.
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