Copper fitting will not heat up

[Tbbarch]

Working on modification to 3/4" supply line in crawl space.

Installing a NIBCO 3/4x3/4x1/2 'T' to supply new toilet.
I have one 3/4 and the 1/2 soldered and good order.

The remaining 3/4 joint did not heat and distribute solder well and did not hold water when the water was turned back ON after cool down.

Trying to disassemble the 'T' starting at the failed 3/4 and now I can not get the fitting end hot enough to even melt the old solder.

- Using a propane torch. I could not get a high flame from the torch when I started because the crawl space was too cold so I keep the torch warm between uses on a heating pad. Currently running a space heater too. I'm guess the temp in the crawl space is 50 degrees.
- The house was drained down and I heated the fitting and surrounding pipe with a heat gun on High for 10 minutes.
-- I also blew out, with my lungs, any water that might be sitting somewhere though that was not necessary during the initial drain down the first time I attempted to solder this fitting.

Any ideas what is going on?

 

[Standardairconditioner]

You need to use a Mapp Gas Torch.

Google, Wiki, Youtube is your friend.

 

[Sponsor]

 

[Tbbarch]

You need to use a Mapp Gas Torch.

I can see a hotter flame may be in order but a 400 degree (15% increase) does not sound like enough to make a difference. I did 10 other joints in the same conditions before this joint.

Is there any word on if NIBCO is having quality control issues?

 

[Standardairconditioner]

Is there any word on if NIBCO is having quality control issues?

There is a PROBLEM, but it is not the product.

 

[Tbbarch]

Doing Gsearch and I see mention of damaging the metal from over heating.
That would have something to do with metallurgy.
Can copper be overheated so that it can not be soldered?

 

[Tbbarch]

Okay ... my bad.
I cut the pipe to be able to twist out the pipe from the fitting and to confirm the pipe was dry.
The pipe was NOT dry.

As I work on the new fittings, periodically a tablespoon of water dribbles out the end of the up hill side of the pipe. I went back through the house and made sure ALL valves were open.

I'm still getting some dribbling.
I do not understand where this water is coming from? I did 7 other joints before this one without water dribbling out.
It looks like just enough to be held back by the meniscus of water in the pipe but then what is feeding it?
I crawled under all the supply lines, shaking and lifted anything that looked low.

These pipes are old and there is a film of mineral deposits lining them.
Could that be holding water back?

SO -
how long does it take for house supply lines to drain down?!!

 

[hj]

FOREVER if you cannot create a low point for it to drain out, or stop the "dribbling".

 

[Tbbarch]

"FOREVER" ?

Even the meniscus will dry up eventually.
...
I'm going to go borrow some white bread ...

 

[hj]

NOT if something is continually refreshing the water in the pipe.

 

[Kreemoweet]

It's the rare vessel that does not contain a clinging film of water when "emptied". Just where do you think the water
goes when you heat the pipes to "dry" them out? Well, up into the rest of the piping system, where it condenses
back into liquid water, and slowly dribbles down into your soldering zone. It can take literally days before a cut pipe
stops dripping, even in a supposedly "drained" piping system. And then of course you have all those valves that
do not completely shut off the water ...

 

[Jadnashua]

It does not take much of any water in a pipe to cause problems with either heating it up hot enough for solder, or for the steam pressure to corrupt a still molten solder joint. And, once the joint is contaminated, either from overheating and burning the flux or water, you must take it apart, clean it up, and start over again. Bread can be an issue depending on what is downstream of that joint, too.

 

[Tbbarch]

So what's a mechanic to do?

All valves were open and the supply was not leaking. The house shut-off bleeder valve was off and the drip was 8" below the line I was working on.
I am flabbergasted that this water just decided to show up for the first time while I worked on this project.

When I heat the pipe I expect evaporated water, that lines the pipe, to travel up and out of the near by open value or at least stay away until the heat in the pipe subsides and it can condense again in the work area.

To top it off without any water near the joint I still could not heat it up. I put on a fresh can of propane and put the torch directly on the fitting and finally - too long by all accounts - it melted the solder and sucked it into the joint. Not only was it like this on the original PITA fitting but also the new coupling I had to install 6" away from it on the same pipe.

That end of the pipe is cursed.
I am going back down to turn the water back on ...

 

[Smooky]

Stuff a wad of soft bread into the pipe to stop the trickle of water temporarily.
https://www.youtube.com/watch?v=3Eu_2I4uQHM
https://www.youtube.com/watch?v=g83YSnKp0jA

 

[Dj2]

To get rid of nagging water drops, heat the pipe and let the drops steam away. This will give you a few seconds to complete your soldering before more drops appear.

 

[hj]

As soon as you apply heat to the pipe, it breaks down the surface tension of the water in the pipe and that causes it to drain down to your location. "Mechanics" have many ways to eliminate the water, depending on the situation.

 

[SteveW]

Okay ... my bad.
I cut the pipe to be able to twist out the pipe from the fitting and to confirm the pipe was dry.
The pipe was NOT dry.

As I work on the new fittings, periodically a tablespoon of water dribbles out the end of the up hill side of the pipe. I went back through the house and made sure ALL valves were open.

I'm still getting some dribbling.
I do not understand where this water is coming from?

A couple of sometimes overlooked valves to make sure are opened are 1) outside hose bibs and 2)toilet fill valves (flush toilets after water shut off).