What is wrong here?

[PlumbIt]

I was told that I should not have that elbow after the P-Trap. Is that correct?

Also, the location of the RO drain is not good. I was going to put a loop in the 3/8 RO drain under the wall tube and then back in the top. That way no sewer gas can escape to the air gap (i.e., the RO drain has its own "P-Trap"). Alternatively, it was suggested that I use one of those dishwasher drain Y connectors with RO drain at the disposal. What do you suggest?

 

[hj]

The RO should connect before the trap. The elbow is okay, although I would not have used a {double slipnut version).

 

[Sponsor]

 

[PlumbIt]

The RO should connect before the trap. The elbow is okay, although I would not have used a {double slipnut version).

Thank you. Would you connect RO with a Y at the DW inlet? Also, how do I eliminate a slip nut? Glued PVC?

You're not going to ask about the piece of downspout? Perfect channel for the faucet weight!

 

[Tuttles Revenge]

The only issue with the 45° elbow is that it is a slip joint. UPC code only allows 1 slip joint after the trap.

Definitely going to have to see how that downspout channel works out. I HATE when my guys install plumbing in the Center of sink bays "cuz it looks good" and the weight smacks or gets hung up on everything!!

 

[Tuttles Revenge]

Thank you. Would you connect RO with a Y at the DW inlet? Also, how do I eliminate a slip nut? Glued PVC?

You're not going to ask about the piece of downspout? Perfect channel for the faucet weight!

You can move that RO saddle to the vertical drop after the disposer. And yes, a glued fitting with a trap adapter would be the suitable replacement.. tho in the grand scheme of things wouldn't be high on my list unless you were already replacing a piece that has a RO hole punched in it.

 

[PlumbIt]

The only issue with the 45° elbow is that it is a slip joint. UPC code only allows 1 slip joint after the trap.

Definitely going to have to see how that downspout channel works out. I HATE when my guys install plumbing in the Center of sink bays "cuz it looks good" and the weight smacks or gets hung up on everything!!

It works like a charm - no noise, super smooth - problem solved. I happened to have a piece of downspout laying around which gave me the idea.

 

[PlumbIt]

You can move that RO saddle to the vertical drop after the disposer. And yes, a glued fitting with a trap adapter would be the suitable replacement.. tho in the grand scheme of things wouldn't be high on my list unless you were already replacing a piece that has a RO hole punched in it.

I don't understand how to incorporate a glued fitting. The Marvel has a compression inlet. The drain pipe that I see is plastic (not glued). I do not see a PVC trap arm for sale (the say PVC but the description is all polypropylene). What would seem ideal is from Marvel - slip joint - PVC - glued PVC 45 elbow - glued PVC trap arm - slip joint - plastic P-Trap ...

 

[PlumbIt]

I don't understand how to incorporate a glued fitting. The Marvel has a compression inlet. The drain pipe that I see is plastic (not glued). I do not see a PVC trap arm for sale (the say PVC but the description is all polypropylene). What would seem ideal is from Marvel - slip joint - PVC - glued PVC 45 elbow - glued PVC trap arm - slip joint - plastic P-Trap ...
View attachment 96165

OK - I will answer myself. Starting from the Marvel: ABS Female NPT/Glue Slip - ABS Straight - ABS 45 Elbow - ABS Straght - ABS 90 Elbow - ABS P-Trap with compression fittings.

 

[Tuttles Revenge]

Its hard to see in the photo clearly what you have to work with. Looks like Black ABS at the wall but either way would be the same process. You need to have at least 3/4" of pipe to work with at the wall to glue a coupling to. Then a piece of pipe with a 45 or street 45 to glue on with a trap adapter glued in the same place as the slip joint 45.

 

[wwhitney]

The only issue with the 45° elbow is that it is a slip joint. UPC code only allows 1 slip joint after the trap.

FWIW, that's not quite what UPC 1003.2 says. It says "one approved slip joint fitting," and that's arguably in addition to the trap adapter (as otherwise the section could be worded more simply, referring only to the trap adapter with no reference to an "approved slip joint fitting").

Cheers, Wayne

"UPC 1003.2 Slip Joint Fittings. A maximum of one approved slip joint fitting shall be permitted to be used on the outlet side of a trap, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps."

 

[Jeff H Young]

FWIW, that's not quite what UPC 1003.2 says. It says "one approved slip joint fitting," and that's arguably in addition to the trap adapter (as otherwise the section could be worded more simply, referring only to the trap adapter with no reference to an "approved slip joint fitting").

Cheers, Wayne

"UPC 1003.2 Slip Joint Fittings. A maximum of one approved slip joint fitting shall be permitted to be used on the outlet side of a trap, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps."

I get that Wayne but when you say arguably That sorta means that there can be argument the other way
It also was probebly intended to outlaw using a nipple like a gal nipple in liew of a proper trap adapter which on a good job aint going to fly . maximum of one and maximum of one additional mean differant things I can see its arguable but after reading that sentance numerous times it seems clear that only a trap adapter is allowed.

 

[Tuttles Revenge]

There are 2 separate fittings after the outlet of the trap. The 45 and the Trap Adapter. Only 1 is allowed.

 

[Jeff H Young]

There are 2 separate fittings after the outlet of the trap. The 45 and the Trap Adapter. Only 1 is allowed.

Thats how I read it as well and I think the r4eason they mention the trap adaper is because they are commonly omited when a gal nipple is sticking out the wall and that practice isnt legal according to this wording. I kinda see waynes point but read it like 10 times and it seems more clear to me

 

[Tuttles Revenge]

A slip joint connection is allowed to be made on tapered trap arms per UPC. Just need to use a flat washer. In the they had to use lead washers.

Chapter - Definitions:
Slip Joint. An adjustable tubing connection consisting of a compression nut, a friction ring, and a compression washer, designed to fit a threaded adapter fitting or a standard taper pipe thread.

 

[Tuttles Revenge]

I don't understand how to incorporate a glued fitting. The Marvel has a compression inlet. The drain pipe that I see is plastic (not glued). I do not see a PVC trap arm for sale (the say PVC but the description is all polypropylene). What would seem ideal is from Marvel - slip joint - PVC - glued PVC 45 elbow - glued PVC trap arm - slip joint - plastic P-Trap ...
View attachment 96165

More like this.

 

[Jeff H Young]

A slip joint connection is allowed to be made on tapered trap arms per UPC. Just need to use a flat washer. In the they had to use lead washers.

Chapter - Definitions:
Slip Joint. An adjustable tubing connection consisting of a compression nut, a friction ring, and a compression washer, designed to fit a threaded adapter fitting or a standard taper pipe thread

I think 1003.2 discuses requirements the definitions are just that definitions but not nessesarily all the requirements involved

 

[wwhitney]

There are 2 separate fittings after the outlet of the trap. The 45 and the Trap Adapter. Only 1 is allowed.

That's certainly one way to count things, and that's what I thought for a while, but if you want to count that way, then you'd just write 1003.2 like this:

"(Alternate Version for Rhetorical Purposes) UPC 1003.2 Slip Joint Fittings. The only slip joint fitting permitted to be used on the outlet side of a trap is a listed tubing trap adapter, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps."

But since they wrote it as below, I'm pretty sure the intention is not to count the trap adapter.

Anyway, that's what my logical reading says; obviously local AHJ interpretation is what matters in the end.

Cheers, Wayne

"UPC 1003.2 Slip Joint Fittings. A maximum of one approved slip joint fitting shall be permitted to be used on the outlet side of a trap, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps."

 

[Jeff H Young]

That's certainly one way to count things, and that's what I thought for a while, but if you want to count that way, then you'd just write 1003.2 like this:

"(Alternate Version for Rhetorical Purposes) UPC 1003.2 Slip Joint Fittings. The only slip joint fitting permitted to be used on the outlet side of a trap is a listed tubing trap adapter, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps."

But since they wrote it as below, I'm pretty sure the intention is not to count the trap adapter.

Anyway, that's what my logical reading says; obviously local AHJ interpretation is what matters in the end.

Cheers, Wayne

"UPC 1003.2 Slip Joint Fittings. A maximum of one approved slip joint fitting shall be permitted to be used on the outlet side of a trap, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps.

There could be more info available in UPC training manuals or something although technically they arent part of the code book itself Ive run aqccross this kind of stuff my entire time in the trade Ive never had 100 percent confidence in every case with one persons opinion or interpetation. Ive also been told that trap adapters are required on tubular traps

 

[Tuttles Revenge]

The beautiful thing about code and law is that they're written with words which can be interpreted. The reasoning behind the code is not explained in the code book and often left out of the training manual.

And to reiterate my initial advice. I would only change that 45° fitting because of the RO placement changing. Otherwise its simply not enough of an issue to worry about. I wouldn't change it out simply to comply with code.

 

[Reach4]

The beautiful thing about code and law is that they're written with words which can be interpreted.

Interpreted creatively? Maybe capriciously, arbitrarily?