There is a 2" pipe coming out of my concrete slab where a basement shower was supposed to be with a glued in trap below the slab. I'd like to use that drain for a sink & ice machine. Can I connect the sink directly to the 2" (with a sanitary wye) and no trap? What about connecting the ice machine's drain directly to the 2" also?

You will always need a trap anytime you connect to a septic or city sewer. Are you planning on a p trap under the sink before it goes into the 2". You may need a vent but one was probably included in the shower setup.

Thanks for answering, ma0641.There is a trap in the 2" below the concrete slab. Here's what I was thinking:1. Install a sanitary tee close the floor. Glue a 90 off the tap, and then put a snap in 2" drain fitting into the 90. Attach the ice machine's gravity drain just above this drain opening.2. Extend the 2" up to another sanitary tee/reducer and connect a 1-1/2" p-trap to the sink basin.3. Extend the 2" up to just below the countertop and cap it with a 2" vent.Sound like a plan?Thanks!

Is this in a commercial place ?

Is this in a commercial place ?
No, it's in my home.

How close is the shower drain to the new sink location ?

How far is the sink and the drain going to be from the shower drain? If not over 5', you will probably be best to install a 2"x4" increasing coupling to the 2" shower drain and indirectly drain the ice maker and the sink INDIVIDUALLY into the drain. Here, the ice maker could have a 1" drain and the sink could have an 1.25" drain... both connect above or just slightly into the increaser coupling.

In this way, the sink drain and the ice maker drain can't cross contaminate, right?

Mark

How far is the sink and the drain going to be from the shower drain? If not over 5', you will probably be best to install a 2"x4" increasing coupling to the 2" shower drain and indirectly drain the ice maker and the sink INDIVIDUALLY into the drain. Here, the ice maker could have a 1" drain and the sink could have an 1.25" drain... both connect above or just slightly into the increaser coupling.

In this way, the sink drain and the ice maker drain can't cross contaminate, right?

Mark

The sink is literally right next to the shower rough in.

What about connecting the sink to the shower rough-in directly and setting up a separate open drain for the ice machine? Would I need a trap for the sink, or can I use the trap that's below the slab?

Need an air gap from the ice maker so it can't siphon back. If there is a p trap in the floor, you don't p trap under the sink. Depending on your local code, double trapping may be prohibited.

Agree. Icemaker drain cannot be connected directly to sewer drain. It has to drain via "open drain", just like in commercial kitchens. That's why I ask you that question before

Both the ice maker and the sink need to connect indirectly to this shower drain... otherwise, the sink would be considered unvented. Use the increaser at the shower drain I mentioned and run separate drain lines from the ice maker and the sink and install so you have a small air gap between the drains and the increaser.

48297

Good luck!