I need to know how to remove a pipe that has been soldered

You're asking how to unsweat a copper fitting? First turn off the water and open the lowest faucet that you have and drain the system. The pipes HAVE to free of water to melt solder. If enough water remains in the pipes to prevent the solder from heating then you will have to cut the pipe with a set of copper cutters and remove ALL the moisture. Next fire up your torch and apply heat to the fitting to be removed. When the solder melts and begans to run take a pair of pliers and twist and pull at the same time while applying heat from the torch. Whatever you wish to unsolder should come apart now. If you need instructions on how to solder a copper to copper joint just click on back and I'll be glad to walk you through it. Good luck and thank you for rating my reply. Tom