# 3 Compartment Sink Drains



## JWBII (Dec 23, 2012)

Gentlemen I'm going to be doing several 3 compartment sinks and all I can ever remember being taught to order in order to connect to the strainers are female adapters. It seems that female adapter threads and strainer threads are not the same and they can only go on a little bit.

What do you guys suggest? 

How have any of you ran your indirect drains on these sinks? 

What fittings do you like to use on these sinks?

Any pictures would be great as well. If I remember right I have to hard pipe these so slip nuts and chrome will not be allowed.


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## benrich07 (Jun 4, 2013)

You can do either 2" dwv copper with a female adapter on the rotary drain or 1.5" with a male adapter into the rotary drain. I have done both it is not difficult at all


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## Plumberman (Jul 7, 2008)

benrich07 said:


> You can do either 2" dwv copper with a female adapter on the rotary drain or 1.5" with a male adapter into the rotary drain. I have done both it is not difficult at all


Was thinking the same thing...


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## crown36 (May 21, 2013)

JWBII said:


> Gentlemen I'm going to be doing several 3 compartment sinks and all I can ever remember being taught to order in order to connect to the strainers are female adapters. It seems that female adapter threads and strainer threads are not the same and they can only go on a little bit.
> 
> What do you guys suggest?
> 
> ...



Do you know which compartments you can run indirect waste and which you can connect to the sanitary system? (Ie; wash, rinse and sanitize).

Will you have a food waste grinder? Solids interceptor? Will there be a grease trap involved/required?


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## JWBII (Dec 23, 2012)

No those aren't things I know at the moment. They are all running to floor sinks. The strainers are already installed in the sinks and they are male. I believe the threads are straight threads while copper fip are tapered so they will barely thread.


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## benrich07 (Jun 4, 2013)

Standard basket strainers??


If that's the case you may have to come off the strainers with flange tailpieces and then transition to dwv copper


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## crown36 (May 21, 2013)

benrich07 said:


> Standard basket strainers??
> 
> 
> If that's the case you may have to come off the strainers with flange tailpieces and then transition to dwv copper


 I have never seen tubular plastic under a commercial 3 compartment sink. Least here anyways. SCH 40 all day long.


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## JWBII (Dec 23, 2012)

Yeah it's chrome and copper only on this job, no plastic.


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## benrich07 (Jun 4, 2013)

If I were doing this I would put in rotary drains, and go dwv all the way to floor sink. If they don't wanna pay for that then I would go with brass or chrome off the strainer and transition to dwv with brass adapter


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## JWBII (Dec 23, 2012)

Rotary drains aren't happening. Drains are supplied by the kitchen equipment guys so I get to work with what's supplied. No biggie to me, just wanted to see what all advice you guys had to offer


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## Marlin (Aug 14, 2008)

The kitchen guys always give us strainers with threads for a nut. Being that we aren't getting paid to supply the strainers so long as it will pass we put it what we are given. 

What we are allowed to do is use tubular brass extra heavy (I forget the gauge) tailpieces coming off the strainers then schedule 40 PVC to the floor sink. They just started allowing the PVC about two years ago.


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## MDPlumber1977 (Mar 4, 2013)

I use 1-1/2" or 2" No Hub Bands right on the threads of the strainer. Works like a champ every time and is especially effective when you have to offset the indirect waste tight to the sink.


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## theplumbinator (Sep 6, 2012)

JWBII said:


> Rotary drains aren't happening. Drains are supplied by the kitchen equipment guys so I get to work with what's supplied. No biggie to me, just wanted to see what all advice you guys had to offer


I would refuse to install their ghetto sink strainers, they're not what the job requires. Either use rotary strainers or go get Kohler brass basket strainers. At least if you have to use a basket strainer the Kohler has real threads that a female adapter will screw on to. Anything else will be a call back for you later. Unless you run all three bays indirect. You should only have to run the sanitize bay indirect though. Ive been through exactly the same scenario before myself.


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## Rando (Dec 31, 2012)

I use 1 1/2" copper FIP's on regular basket strainers sometimes. On vegie sinks and prep sinks that's usually what you get from the kitchen equipment supplier. I've seen lots of flanged tailpiece into trap adapter type set ups. They always fall apart. 
You have to file down the first few threads on the FIP. It's a solid connection and I've had no leaks.
Never done it on a three compartment though. All the three compartment sinks I've done have had the commercial strainers with 2" male and 1 1/2" female.


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## JWBII (Dec 23, 2012)

Let me back up. My title should have been different. The three compartments are actually perfect for a change. The fip will thread right onto the threads without a problem. The last ones I did were regular strainers and the threads would barely go on which is why I wanted to ask before I got started.

The 1 1/2 one however is a standard strainer where the threads will barely work. I don't have the option of just refusing to do what they want nor to just use what I want. This isn't my company and if it results in a call back that won't be my fault. I don't want to use flanged with compression as I do feel they will fall off. I never thought about the no hub idea.


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## theplumbinator (Sep 6, 2012)

JWBII said:


> Let me back up. My title should have been different. The three compartments are actually perfect for a change. The fip will thread right onto the threads without a problem. The last ones I did were regular strainers and the threads would barely go on which is why I wanted to ask before I got started.
> 
> The 1 1/2 one however is a standard strainer where the threads will barely work. I don't have the option of just refusing to do what they want nor to just use what I want. This isn't my company and if it results in a call back that won't be my fault. I don't want to use flanged with compression as I do feel they will fall off. I never thought about the no hub idea.


Well I guess just load up the threads with blueblock. First thing I do when I have to install one of those sinks is throw the three crummy stamped $5 strainers in the garbage. And say it never came with any if someone asks.


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## justme (Jul 4, 2012)

JWBII said:


> Let me back up. My title should have been different. The three compartments are actually perfect for a change. The fip will thread right onto the threads without a problem. The last ones I did were regular strainers and the threads would barely go on which is why I wanted to ask before I got started.
> 
> The 1 1/2 one however is a standard strainer where the threads will barely work. I don't have the option of just refusing to do what they want nor to just use what I want. This isn't my company and if it results in a call back that won't be my fault. I don't want to use flanged with compression as I do feel they will fall off. I never thought about the no hub idea.




On those types of threads I will take the female adapter and heat it up and it will thread right on to the basket strainer no problems.


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## MTDUNN (Oct 9, 2011)

Most 3 compartment sinks come with cheap basket strainers. I always throw them out and use rotary drains for commercial applications. Or I will use double cups for bargain jobs. 

You can't fit a square peg in a little round hole.


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## Andrew G (May 27, 2013)

Inspectors in Seattle are usually fine with 1.5" no hub bands connecting standard strainers to schedule 40 abs. Pretty easy to disassemble and clean. 
If they're stop and waste style strainers, it seems that more cop dwv is spec'd out, we use a 2" fip that works pretty well, then if a grease interceptor is to be installed , it's vented and tied into the sanitary. If none then all the compartments are indirect into the floor sink with a cleanout at the first compartment upstream. Love seeing them direct connected, clogged, and no way to get a snake in the line.... Not.


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## aldridgeplbg (Dec 26, 2011)

*3 comp drains*

the way that i have done this what you are talking about i believe is to take brass flanged tailpiece and sweat them inside of 1 1/2 " copper if you are going to do dwv copper. Plastic I take a copper pencil reamer and ream the top of a 1 1/2 pvc female and thread it on if they are cheap basket strainers hope this helps


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