How to replace an old utility sink trap

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six50joe

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So the other day I clumsily dropped something down our laundry room sink. I thought no biggie, I'll just remove the trap and dump it out. Removed the nuts from the p-trap which were hard to turn because it's 30 yrs old with some corrosion. To my chagrin, the thing I dropped wasn't there, but it got worse.

I tried to put it back in, hand tightening both nuts, but it leaked. Long story short, I couldn't get it to not leak, trying to position the washer correctly and tighten the wall-side nut, which finally broke when I put some elbow grease into it.

I don't know how to get the wall 'arm' (correct me if wrong term) off so I can replace it along with a new trap.

The first pic shows what I saw with the trap off. The second is a close up of it after removing the flange on the wall from the pipe. At the moment, I can't tell if the pipe is soldered to the one coming from the wall, or if it is all one piece with that section in it. I just want to fix it so I can use my utility sink again. Any advice on what to try? Really hoping the solution doesn't involve opening up the wall. :eek:

IMG_5620.jpg


IMG_5622.jpg
 
Yes it appears the trap is soldered into a piece of 1 1/2" cooper. You will need a plumber. You might be able to cut that piece and put a 1 1/2" jam nut coupling on there and then a pvc trap.
 
Thanks for your adivce . I suppose I will have to get a plumber, but would like to look into the other option you suggested first. I've used jam nuts on threaded rod before, but I wasn't aware they could be used for 1 1/2" pipe. I searched for that type of use online but couldn't find anything. Is there a particular piece of hardware made for this use in plumbing, or is it something you need to rig yourself using 1 1/2" nuts?
 
If it were my house, I would un-solder the wall arm from the copper stub, and then solder in a 1 1/2" trap adapter. I would then get an 1 1/2" P trap and reinstall.
 
Thanks for all the advice. I haven't done anything with it yet, which is probably a good thing.

For the slip nut coupling solution- I haven't used one of these before. Is the nut designed to fit over the flanged part of the wall arm before tightening, or does the pipe need to be cut shorter with a hacksaw or something?

For the wall arm unsoldering solution- I've worked on a few projects desoldering electronics, but not with plumbing. What is the reccomended tool for desoldering? I'd imagine it's not an iron. Would I use a butane torch or something similar?
 
On the slip nut coupling the pipe needs to be cut. Use a hacksaw very carefully. What size is the p-trap?
 
To unsolder, I would use a Mapp gas torch (yellow). You could also use a butane torch (blue), but it will take a little longer. Use the same torch, along with sandpaper Flux and solder, to solder on a trap adapter. When soldering, remove the nut and bevel washer from the trap adapter. Once done, it is a simple task to install a p-trap. I would recommend a plastic, rather than a chrome p-trap.
Thanks for all the advice. I haven't done anything with it yet, which is probably a good thing.

For the slip nut coupling solution- I haven't used one of these before. Is the nut designed to fit over the flanged part of the wall arm before tightening, or does the pipe need to be cut shorter with a hacksaw or something?

For the wall arm unsoldering solution- I've worked on a few projects desoldering electronics, but not with plumbing. What is the reccomended tool for desoldering? I'd imagine it's not an iron. Would I use a butane torch or something similar?
 
Thanks. PVC trap adapters are also readily available at my nearest big box store. Is it possible to use of these with the copper tube coming from the wall? It's in a pretty tight area, would prefer to avoid soldering if possible due to the cramped space it's in if the result will work just as good.
 
If you insist on not soldering, you could get a "fernco" rubber coupling (with a metal shield aka mission coupling) that connects 1 1/2" copper to 1 1/2" PVC. Then a short piece of 1 1/2" PVC and then glue in the PVC trap adapter.

When choosing the fernco make sure it says copper to pvc.
 
Thanks again. Soldering a copper adapter sounds like a better permanent solution, and I'm sure is a routine plumbing task, but I haven't done it before. It's probably worth pulling up my big boy boots, preparing properly and trying it though, because I'll have confidence to do it again in the future. As a first step I'll be finding out how easy or hard it is to desolder the existing tube.
 
If your not comfortable to soldering this fitting then don't. Don't need any fires. Cut the pipe off and do
like what was said. Get the copper to plastic mission coupling and also you can buy a fitting trap adaptor and
then you don't need to glue any pipe and it gives you a little more room for the arm of the p-trap. Hope this
helps you some.
 
Tom - by "fitting trap adapter", I am assuming you mean what I call a "street trap adapter", such that rather than adding a short piece of pvc pipe, the trap adapter would fit in one end of the mission coupling and the existing copper pipe would go into the other end of the mission coupling. I am not a pro, but I do plenty of plumbing on my rental properties. I just want to make sure that I understand your recommendation.
If your not comfortable to soldering this fitting then don't. Don't need any fires. Cut the pipe off and do
like what was said. Get the copper to plastic mission coupling and also you can buy a fitting trap adaptor and
then you don't need to glue any pipe and it gives you a little more room for the arm of the p-trap. Hope this
helps you some.
 
Tom, when you say I could by a fitting trap adapter, do you mean that it's not necessary, but would make it easier to change out a trap in the future, as opposed to putting the trap PVC straight into the coupling?
 
Jeff, you are correct. Everybody has a different name for some things. Another name for it is a fitting desanko.

Joe, you put the mission coupling on the copper. Then the fitting trap adaptor on the other end. Here is a picture
of what one looks like.fitting trap adaptor.jpg
 
I went with the coupling / polyethelene p-trap solution. It was a pain to cut the existing wall pipe short due to the small space it was in. The cut wasn't silky smooth, but other than a small crimp at the end, it looked smooth enough.

I didn't end up using the 1 1/2" trap adapter because it wouldn't fit into the 1 1/2" coupling I bought. I'm assuming the OD of the larger side of the adapter requires a larger coupling (assuming no problems with this?) I just ran the plastic trap into the coupling. Tested it thoroughly, no leaks. Not as nice looking as the soldering solution, but am happy to have our laundry sink back.

Thanks again for all advice.
 

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