Soldering copper plumbing pipes

[FP]

I am replacing a tub in our master bathroom today and was working on the inlet copper lines. I soldered everything together and turned on the water to the house. The soldered joint held for about 4 minutes and then the elbow joint on the cold water pipe burst off.

I turned the water off, dried the pipes and tried to resolder the joint. This time there was an immediate little stream of water that came shooting out of the joint.

I tried one last time and the joint held. It has been working for the last 5-6 hours.

Did I just do a crappy solder job? I have only done 3-4 plumbing soldering jobs in my life and have never had a problem before. I am very reluctant to close the wall and tile out of fear the thing will burst again. If a soldered joint holds under full pressure for a while is the likelihood of it failing pretty slim?

UPDATE: Well, the good news is the joint referenced above hasn't been a problem. The bad news is a different joint failed and I woke up to a garage full of water. It was literally raining in my garage. The joint that failed wasn't completely soldered all the way around I guess. I spent the morning cleaning up the mess and resoldering the line. Hopefully the drywall isn't damaged. I was more worried about the electrical as it was coming through the hanging lights. Bah, next time I think I'll just hire a professional to do the plumbing. This sucks.

 

[FoBoT]

Originally posted by: binister


Did I just do a crappy solder job?

apparently

what did you use? a propane torch?

 

[FP]

Originally posted by: FoBoT

Originally posted by: binister


Did I just do a crappy solder job?

apparently

what did you use? a propane torch?

Yep, the standard blue benzomatic torch.

I would really hate for the joint to fail while I am away. This is the first "in wall" soldering job I have done.

 

[FoBoT]

weird, unless you have water leaking into the joint when you are doing it, it is pretty easy


just give it a couple days before you close it up, better safe than sorry

 

[ric0chet06]

did you clean the pipe ends with emory cloth? Then flux the ends?

 

[sierrita]

Originally posted by: binister
I am replacing a tub in our master bathroom today and was working on the inlet copper lines. I soldered everything together and turned on the water to the house. The soldered joint held for about 4 minutes and then the elbow joint on the cold water pipe burst off.

I turned the water off, dried the pipes and tried to resolder the joint. This time there was an immediate little stream of water that came shooting out of the joint.

I tried one last time and the joint held. It has been working for the last 5-6 hours.

Did I just do a crappy solder job? I have only done 3-4 plumbing soldering jobs in my life and have never had a problem before. I am very reluctant to close the wall and tile out of fear the thing will burst again. If a soldered joint holds under full pressure for a while is the likelihood of it failing pretty slim?

Yes, if it holds under pressure for several days, it's not likely to fail after that.

I don't want to sound condescending or anything, but did you thoroughly clean (wire brush or sandpaper) all fittings? Use good flux? Proper plumbing grade solder?

 

[nutxo]

heat the joints and let it suck the solder in. Make sure to clean pipe ends and flux.

 

[PottedMeat]

Did you do all that cleaning/emery cloth stuff on the joint?

Did the solder wick into the joint?

 

[FP]

Hmm... I had wondered if the problem was because the "exhaust" from the soldering had no place to go since it was the final solder. I didn't think to open the valve line. Oh well.

FoBoT: Have you ever had a plumbing solder job fail? If so, did the subsequent solder jobs hold or did you start fresh with new pipes/joints?

 

[FP]

Yes, I cleaned the inside/outside of both the pipe and the joint, put regular ol' plumbing flux on the pipe and soldered it as I normally do (heat pipe till flux sizzles, remove flame and touch solder to pipe). The front of the pipe has a nice clean shiny solder but I can't see the back of the pipe because it is recessed in the wall.

Anyway, I guess my main question is if the joint holds for a few hours/day is it pretty safe to assume it will hold for good or have people experienced otherwise?

 

[FoBoT]

i haven't done a lot , but the only time i had any problems was when some water was leaking into the joint while i was doing it, it kept cooling off the pipe, so it was really hard to get it to stick

 

[dartworth]

If it isn't leaking by now, you should be ok.

You should trying soldering some 6" copper pipe...

 

[NoShangriLa]

It is very likely that you burnt the copper joint/s therefore the carbon built up repelled the solder. Or, you didn't heat the copper to proper temperature to ensure solder flow.

Try turn the water on/off quickly several times after you shake the copper pipe to see if it holds. Also, keep an eye on it in the next few days to see if it develop leaks.

It might be beneficial to leave the soldering to the guys that do it for a living and use copper glue, quick connect sharkbite fittings (rated for cold & hot water up to 200F), or quick connect John Guest fittings (rated for cold water usage).

 

[kindest]

they have glue now for copper..
just-4-copper.. its pretty neat stuff.
dries in like 5 minutes.. and will hold up to like 900psi or something redicolous..
ive used it on my bathroom.

 

[NoShangriLa]

Originally posted by: binister
Hmm... I had wondered if the problem was because the "exhaust" from the soldering had no place to go since it was the final solder. I didn't think to open the valve line. Oh well.

FoBoT: Have you ever had a plumbing solder job fail? If so, did the subsequent solder jobs hold or did you start fresh with new pipes/joints?

Positive pressure shouldn't be a problem if there is a long pipe run, or you could simply open a valve some where in the house to relieve pressure.

[add] I have had 1 solder joint failed however the 1" copper was touching the wood frame at the back side. I have fixed many poor copper joints that others worked on (up to 4"), and most of them by persistently add flux to the heated joint to wash away the carbon built up. Larger pipings sometimes require de-sweat and re-sweat to get a proper joint.

 

[FP]

Update in first message.

 

[Pacfanweb]

Originally posted by: nutxo
heat the joints and let it suck the solder in. Make sure to clean pipe ends and flux.

Yep. It's called Sweat Soldering.

The sandpaper is the key.

 

[TheoPetro]

as long as you didnt overheat the pipe the solder will be drawn into the crevice between the pipe and the fitting and there wont be any problems. If you did over heat it then the solder will melt into the fitting and youll have holes.

 

[BUTCH1]

Originally posted by: NoShangriLa

It is very likely that you burnt the copper joint/s therefore the carbon built up repelled the solder. Or, you didn't heat the copper to proper temperature to ensure solder flow.

Try turn the water on/off quickly several times after you shake the copper pipe to see if it holds. Also, keep an eye on it in the next few days to see if it develop leaks.

It might be beneficial to leave the soldering to the guys that do it for a living and use copper glue, quick connect sharkbite fittings (rated for cold & hot water up to 200F), or quick connect John Guest fittings (rated for cold water usage).

Wow, never new about sharkbite fittings until now..I replaced my own HW heater (home depot wanted $195 to install it) used
solder and all went fine. Next project/repair Sharkbite fittings or the just-4-copper glue look much simpler..

 

[compuwiz1]

How is it safe to drink water, after using nasty chemicals and solder, which has lead in it, to connect plumbing? :laugh:

 

[TheoPetro]

Originally posted by: compuwiz1
How is it safe to drink water, after using nasty chemicals and solder, which has lead in it, to connect plumbing? :laugh:

solder doesnt have nearly as much lead as it used to. There is still 50/50 solder but that isnt approved for use in any consumable water lines. I think (could be wrong) whats used now is 90/10. The flux is all burnt off by the time any water touches it anyway. The pipes are also flushed.

I thought you were being sarcastic but just in case you actually worried someone.

 

[dartworth]

Originally posted by: compuwiz1
How is it safe to drink water, after using nasty chemicals and solder, which has lead in it, to connect plumbing? :laugh:

solder that is used on potable water does not and should not contain ANY lead...

 

[drnickriviera]

Originally posted by: binister
Yes, I cleaned the inside/outside of both the pipe and the joint, put regular ol' plumbing flux on the pipe and soldered it as I normally do (heat pipe till flux sizzles, remove flame and touch solder to pipe). The front of the pipe has a nice clean shiny solder but I can't see the back of the pipe because it is recessed in the wall.

Anyway, I guess my main question is if the joint holds for a few hours/day is it pretty safe to assume it will hold for good or have people experienced otherwise?

Tip, solder from the blind side of the joint first. Take the solder and bend it to a J shape. You should see the solder flow to the front side.

You did heat the joint not the pipe correct? Put the heat where you want the solder to go.

I've done hundreds of joints and never had one blow off like that.

 

[slsmnaz]

Go rent a Propress machine and be done with it. No need to solder anymore

 

[JDub02]

Originally posted by: drnickriviera

Originally posted by: binister
Yes, I cleaned the inside/outside of both the pipe and the joint, put regular ol' plumbing flux on the pipe and soldered it as I normally do (heat pipe till flux sizzles, remove flame and touch solder to pipe). The front of the pipe has a nice clean shiny solder but I can't see the back of the pipe because it is recessed in the wall.

Anyway, I guess my main question is if the joint holds for a few hours/day is it pretty safe to assume it will hold for good or have people experienced otherwise?

Tip, solder from the blind side of the joint first. Take the solder and bend it to a J shape. You should see the solder flow to the front side.

You did heat the joint not the pipe correct? Put the heat where you want the solder to go.

I've done hundreds of joints and never had one blow off like that.

Yep, I just did an in-the-wall solder joint a few months ago when a pipe burst from freezing. Much easier to start at the back and work forward with the solder. Joint has held up for 2 months now and still good ... and I'm far from a professional.