How to Properly Fix a Leaky Copper Pipe Plumbing Fitting
Copper pipe fittings often leak because the joints were not soldered well when they were first installed or if the joint is so old that it is not watertight anymore. Regardless of the reason why they became leaky, fixing them requires you to remove and resolder the joint so it is watertight again. The task seems challenging, but it actually is not as hard as it looks. Solder does not have a high melting point, and just needs to be reheated. No need for adding more solder, although doing so helps ensure that the joint is truly watertight afterwards.
1. Switch off the valve that is supplying water to the part where the leaky joint is located. The valve to switch off can be the small one that is located near the affected joint or the water main valve. Switch the latter off, and you cut off the supply of water to the whole house.
2. Get a lighter or match and striker and light a hand torch. Use the lit torch to heat the joint, and once it is hot enough, detach the pipes from the fitting and wipe any excess solder from the ends connected to the fitting. Toss the old fitting away.
3. Once the pipe ends have cooled, get emery cloth and rub all the ends with it. This cleans the ends and helps them accept new soldering easier. Once you have cleaned the pipe ends, brush flux on them, and then connect a new fitting to them. Unroll approximately twelve inches of solder so it is ready once both fitting and pipe are hot enough.
4. Start to heat pipe ends, making sure to work one pipe at a time. Once you have sufficiently heated the fitting, the solder will melt as soon as it touches the former. Apply solder to the end part of the fitting, making sure to run it all throughout the copper piece. Do this same step with the other pipes you will connect with the fitting.
5. Once the fitting has cooled, switch the water supply on to check if leaking is still going on. You should also do this since the flow of water also helps cool the fitting. Repeat the first three steps if the fitting still leaks. Contact a plumber for further assistance if the joint is still leaky despite repeated attempts to sort the problem out.