Where to Install an RO Drain Saddle?

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Installing the drain saddle of a reverse osmosis system may seem like an easy decision, but it could potentially lead to some issues if you don’t take some time to familiarize yourself with the situation beforehand.

You should keep a few general precautions in mind to ensure the optimal performance of your RO system.

So, where to install an RO drain saddle?

Key Takeaways

  • A reverse osmosis drain saddle should be installed above your drainpipe’s P or J-Trap, and upstream and as far away from any garbage disposal as possible.
  • Ideally, you install the drain saddle on a horizontal pipe section. Vertical works, too, but this may occasionally produce unwanted noises.

The Right Location: Where Should You Install Your Reverse Osmosis Drain Saddle?

What’s the best location to install a reverse osmosis drain saddle?

The main considerations to make for the installation location are whether it should go before or after the P-trap and whether it should be installed horizontally or vertically. If you have a garbage disposal, you’ll want to take that into account as well.

Under Sink Reverse Osmosis System

Above the Drainpipe’s J or P-Trap

Always install the RO drain saddle above the P-trap of the drainpipe (or the J-trap if that’s what you have).

Otherwise, your drain will not work correctly and you may run into issues with the reverse osmosis system later on.

Horizontally or Vertically

While you’re free to install an RO drain saddle vertically or horizontally, you should always aim for a horizontal installation if you have the choice.

The drain will still work correctly when put on a vertical pipe section, but it may produce unwanted noise from time to time.

If you do go horizontally, remember to install the drain saddle on the top or side of the drain pipe but never the bottom.

Upstream of Garbage Disposal

Always install the RO drain saddle away and upstream from your garbage disposal unit if you’re using one.

To close/downstream to the garbage disposal and your drain line will eventually get clogged with debris and not function correctly. Sometimes this may be unavoidable – in this case, consider using an extension pipe to move the drain saddle away from the garbage disposal.

Drain Saddle Valve Installation Procedure

Here is the process for how to install a drain saddle valve:

  1. Choose a suitable location for your drain saddle valve and mark it.
  2. Drill a hole (1/4”) through the side of the pipe facing the mark.
  3. Attach the adhesive side of the gasket to the drain clamp so it goes around the pipe and over the hole.
  4. Align the drain saddle on both sides – use a small tool like a screwdriver to verify that they are properly set.
  5. Tighten the drain saddle clamp using the included bolts. Apply gentle pressure but don’t overtighten.

If you have any thoughts about the question, where to install an RO drain saddle, 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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