View Full Version : Installing pvc p-trap .. how to connect to metal pipe from wall (no threads)

05-08-2011, 12:41 PM
A few days ago our pedestal sink started leaking, so yesterday I started looking around and noticed that the pipe going to the p-trap is leaking. While moving the pedestal, the minor shocks completely broke the pipes going to p-trap and going to the wall. so I went to Home depot and bought new sink popup drain (pvc, expandable with chrome top, 1-1/4") and new pvc p-trap (1-1/2" because I thought the old chrome one was 1-1/2")
Then I noticed that the metal pipe coming from the wall has no threads. I am guessing that the pipe corroded and the threaded part broke down. (Is that galvanized steel?) Here are couple of photos. The ID of the pipe is 1-1/2" and OD is 1-3/4")



I couldn't pull out the escutcheon completely. Here is a picture of behind the escutcheon.


So question is how do I connect all this together?

After some reading around forums, I came up with this idea ..
Use fernco reducer rubber coupling (http://www.amazon.com/Fernco-P1056-150-Flexible-Reducer-Coupling/dp/B000BQ7TAM) and connect a 1-1/4 threaded on one side pipe to this wall pipe, buy another 1-1/4 p-trap and connect that p-trap to the pvc popup drain on inlet side and this metal threaded pipe on the outlet side. Does that seem right? Is there a better way?


05-08-2011, 12:54 PM
I do not really know what you have there. That "bell" escutcheon is concealing something inside it because the pipe on the left is bigger than the one on the right next to the bell, but it could be a "cover tube" over a copper drain pipe. Remove the bell and then take a picture.

05-08-2011, 01:35 PM
I do not really know what you have there. That "bell" escutcheon is concealing something inside it because the pipe on the left is bigger than the one on the right next to the bell, but it could be a "cover tube" over a copper drain pipe. Remove the bell and then take a picture.

I didn't quite understand the pipe on the left and the right part .. but I got up close at the color change in the pipe and noticed that there is level difference when the brown changes to chrome. It seems like a chrome pipe is fitted over a copper pipe and soldered at the end. Here are couple of close-ups of that area right near the wall



05-08-2011, 01:52 PM
Yes , your trap arm was soldered to a copper pipe in the wall. You could have the broken piece removed and redone. Or you could solder a threaded trap adapter onto the stub. You may not be able to cover that with a bell escutcheon.
Easiest, but "ugliest" ,given that this is apparently a pedestal sink, is fernco rubber adapter clamps.


05-08-2011, 02:01 PM
Thanks Jimbo .. Now I will have to figure out how to remove the soldering and if the trap arm will then come out easily ..
Is that a doable job for a decent DIYer?

Is soldering a new trap arm like copper pipe soldering? I assume this will be easier since the trap arm is over the copper pipe and there is enough overlap?

Need to learn new tricks now .. If the family will accept another few days of inconvenience

Any tips n tricks? links for how to do this etc?


05-08-2011, 04:07 PM
It looks like that chromed piece is just soldered onto the copper pipe. No rocket science in removing it - you heat it up and slide it off. Normally, you'd use a compression fitting (desanko) that was soldered onto the stub. To get that new piece installed, you'd want to use a cotton rag to wipe the excess solder off of the stub after you pull the sleeve off of it. If you don't get enough off, you may need to sand it down a little so the new piece will fit. A deep bell escution might cover the whole thing to make it pretty, if required. then, you'd slide the end of the trap arm into it and tighten the compression fitting. With the 1-1/2" pipe you have, you'd have to have a 1-1/4" trap, or it wouldn't fit.

05-10-2011, 11:03 AM
Thanks Jim .. 5 minutes of soldering torch heated it enough to take the chrome out. And the house is not on fire (yet!) I am hoping that I did not burn something inside the wall while the flame strayed a bit.

The HD guys told me to get 1-1/2" schedule 40 PVC trap. They didnt have 1-1/4" schedule 40 trap. They did have 1-1/4" traps, but the guy there said, don't use it, its flimsy and not really good to use. And the trap adapter wouldnt fit PVC 1-1/2" trap arm as you said. So at the moment I am going with Mission CK 115 connector (http://www.missionrubber.com/Products/BandSealCouplings.php) between the copper pipe (1-1/2") to PVC pipe (1-1/2")

Here are pictures of taking out chrome sleeve to help out new DIYers in future ..



05-10-2011, 01:15 PM
You have a copper stubb,clean it up with sand cloth till it bright and shiny,then solder on a new trap adapter(desanko).

05-10-2011, 01:58 PM
If you don't like the 1-1/4" stuff available at the big box stores, check out a plumbing supply shop, or, spend a bit more money and get a heavy gauge chromed brass unit. The proper fitting to connect your trap arm to the wall is readily available.

05-10-2011, 05:59 PM
So now everything is dry fitted. Looks good .. I think I am done for the day. Tomorrow I will install the popup drain (with plumber's putty at the drain) cement all PVC pieces and tighten the coupling .. Point out any omissions .. give any suggestions ..

I will do desanko adapter later in a few months. (We are replacing the pedestal with a vanity, that would be good time. Also I am going to change the location of one of the outside faucets so I will be doing some soldering to get some practice.) That adapter and PVC 1-1/4" P-trap will be the improved solution ..

Thanks all for your help