17+ How To Remove Solder From Copper Pipe PNG. Can those connections to the elbows be heated and the solder removed, the pipe cleaned, and a new section of pipe soldered to the same elbow connections? If all else fails, you can try removing the solder from your old copper pipes by rubbing it with some sandpaper.
Also recognize that sweating a large copper drain line calls for a large propane torch;
Do not solder copper fittings that are directly connected to valves, water heaters, faucets etc. Copper pipes are often used for carrying potable water to sinks, showers, sprinklers, washers that's because copper is durable and resists corrosion. You could always solder on new shut offs as a fall back if you nick the pipe. While repairing electronics we often need to unsolder some element from a printed circuit board.