P-trap newbie

Users who are viewing this thread

thebordella

New Member
Messages
22
Reaction score
0
Points
0
Location
Ithaca, NY
Hi all,

In my previous post about a water supply line problem (resolved: https://terrylove.com/forums/showthread.php?t=32787) I attached some pictures (one also attached here). You can see here the remaining section of drain pipe left after I removed the old vanity.

The reason this section of drain is remaining is because I don't know what I am doing. The old sink had old metal sections of pipe - both straight and curved - that eventually connected to a curved plastic section (almost like two P traps in sequence or something -- I don't know, but there was more than the one "curve" you see in a typical P trap diagram). I had no luck undoing the metal couplings so I simply cut right through a section of the plastic pipe. The remainder is what you see here. I decided at the time I would deal with this problem later.

Well, it is now later!

I've looked at diagrams of P traps. My first question is, why does the waste line in my picture curve pointed up? In all the diagrams I see for a P trap, the line curves down after the straight stub out from the wall. (As you can guess, I am not the original owner of this house, so I don't know why things are the way they are.)

My intent is to put a new vanity in and hook up the sink. What do I need to do to get from what you see here to a typical P-trap to the sink? I'd like to use plastic wherever possible. Are there any approaches that don't involve solvents to join the sections? How do I unjoin the sections you see there now?

thanks!
-Aaron
 

Attachments

  • pipe1.jpg
    pipe1.jpg
    34.6 KB · Views: 2,694

Gary Swart

In the Trades
Messages
8,101
Reaction score
84
Points
48
Location
Yakima, WA
I would cut the elbow and coupler off, leaving just a stub sticking out. The P trap, sometimes called a "J" or "U" trap, comes down from the sink then curves back up toward the sink (like a "U" ), then turns 90 degrees and goes into that stub coming out of the wall. The actual connection to the drain requires a threaded adapter glued on the PVC pipe with a slip joint connector screwed to that. All of the connections from the sink to the drain are made with slip joints connections that are just hand tightened. The reason we cut that elbow off is connecting downward into that would create what is called an illegal S trap. That's a P trap with an extra curve. Any decent hardware store can assist you in getting the right parts for the p trap. They usually come as a packaged set of pieces with everything necessary.
 

thebordella

New Member
Messages
22
Reaction score
0
Points
0
Location
Ithaca, NY
Thank you, that helps!

Just to clarify, you are saying to cut to the right (closer to the wall) of that white "collar" (coupler?) in the picture? This will leave a short stub but I suppose I can work with that.

I will look for the P-trap kit you describe.

-Aaron

I would cut the elbow and coupler off, leaving just a stub sticking out. The P trap, sometimes called a "J" or "U" trap, comes down from the sink then curves back up toward the sink (like a "U" ), then turns 90 degrees and goes into that stub coming out of the wall. The actual connection to the drain requires a threaded adapter glued on the PVC pipe with a slip joint connector screwed to that. All of the connections from the sink to the drain are made with slip joints connections that are just hand tightened. The reason we cut that elbow off is connecting downward into that would create what is called an illegal S trap. That's a P trap with an extra curve. Any decent hardware store can assist you in getting the right parts for the p trap. They usually come as a packaged set of pieces with everything necessary.
 

Gary Swart

In the Trades
Messages
8,101
Reaction score
84
Points
48
Location
Yakima, WA
Yes, cut the couple and elbow off. You only need an inch or so to glue the threaded male adapter on the pipe.
 

hj

Master Plumber
Messages
33,600
Reaction score
1,037
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
drain

If that elbow and coupling are glued on, then someone who also "did not know what he was doing", made a bad connection previously. I think you may have more problems with that broken hot water connection than with the drain. Another question. If you don't know what you are doing, WHY are you doing it?
 

loafer

Mechanical Engineer
Messages
50
Reaction score
0
Points
6
Location
Maine
If everyone knew what they were doing, there would be no point to this forum.

If that elbow and coupling are glued on, then someone who also "did not know what he was doing", made a bad connection previously. I think you may have more problems with that broken hot water connection than with the drain. Another question. If you don't know what you are doing, WHY are you doing it?
 

Gary Swart

In the Trades
Messages
8,101
Reaction score
84
Points
48
Location
Yakima, WA
HJ questions whether the coupler is glued to the pipe stub coming out of the arm. I rarely disagree with HJ, he's most knowledgeable responder on this forum, but whether glues on not, that's the place to cut what you have to make a P trap. As I indicated before, you almost certainly had an S trap and that needs to change to a P trap. If you will refer to Florida Orange's diagrams, think of the 3/4 S trap that instead of pointing at 45 degrees down, it would come straight out and into the pipe in the wall. That would make it a P trap. There are other things that you need to know such as pipe size, P trap size what male adapter you need, but any good plumbing shop can assist you with that.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks