I agree that there is probably some water left in the pipe. If
you are replacing it anyway, drill or cut a small hole in the
elbow to let water and steam out.

Before you ever attempt it on the real piping, I would suggest the
following:
Go to the store to buy the new elbow you need. Get the solder,
sand paper, flux, and torch that you will need. Get a tubing
cutter also if you need one.

Buy an extra elbow or tee and the shortest piece of copper pipe
they will sell.

Sand the inside of the elbow. Sand the outside of the end of the
pipe. Flux both pieces. Assemble. Sweat together with the torch
and solder. Make sure the pieces are on a brick or some fire safe
surface - NOT the concrete floor. Apply heat to the joint. Keep
the end of the solder touching the copper - you may melt off
several drips. You need to find out and know when the copper is
just barely hot enough to draw the solder. It is possible to get
the copper too hot and not be able to make a joint, but you need
to know the lowest temperature that will work - you can get quite
a bit hotter, but you don't want to get it too hot. Once the
joint starts to draw the solder, remove the heat and continue to
apply the solder until the joint is too cool to melt solder. You
have now put a joint together. Now take it apart!!!! you have
control of all the variables. You have dry pipe, clean copper,
fresh solder, and no tension on the joint. You will need to have
a vise or some way to hold the assembled joint (put your foot on
it if you won't burn yourself). You will need to get the joint
hot enough to melt the solder. Use a pliers to pull the fitting
off the pipe. You will now have reasonable experience of all
that is involved.

Go forth and conquer.
to melt the solder that is holding the joint



(top posted for your convenience)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Keep the whole world singing . . . .
DanG (remove the sevens)




"Phillip944" wrote in message
oups.com...
I'll admit it... I've never soldered anything in my life. So,
to
replace a corroded, leaky copper elbow joint, my father-in-law
instructed me to heat the pipe, pull off the old joint, then
replace
it... after proper preparation, of course.

The problem is that I heated the old elbow, but nothing
happened. I
heated the pipe & the elbow... nothing. Couldn't get it off.

Any suggestions would be greatly appreciated, as I dread the
cost of
having a plumber do what seems to be a simple replacement.