I had the same problem with a copper soldered joint a year ago.....baffled
me for a while....I heated that dang joint until it was red as could
be....but it wouldn't budge. Then I realized that the joint was NOT
soldered with conventional solder, it was silver soldered....which meant
that I would have needed to get out the acetylene torch to loosen the joint.
I ended up cutting the joint and then going from there.

Apparently, some builders silver solder because it's quicker...but makes it
a pain in the behind for homeowners.

Good luck

--
Mark
"ississauga" wrote in message
om...
I am using a propane torch to melt a recently made solder joint
holding together half inch copper plumbing pipes, but the solder won't
melt no matter how long I heat it for. I leaked out the water and
heated once till copper pipe turned red. Is there another way to melt
the solder ?