If you find that your copper pipe needs cleaning due to corrosion, there are a few easy steps to help you.
Step 1 - Prepare
If you do not have direct access to the copper pipe joints then you will need to use a wrench or pliers to remove them to be cleaned. Otherwise, you can wash them in place.
Step 2 - Use Vinegar and Baking Soda
The first thing that you want to try is mixing vinegar and baking soda to make a paste. You can use this solution to rub on the pipe joints and allow it to sit for about 10 minutes. Then take a clean cloth and wipe the paste off. Be aware that the mixture will bubble excessively at first so add the ingredients gradually.
Step 3 - Use Soap
For smaller or hard to get to areas use a toothbrush, and for larger you can use a cleaning pad. Put soap on either the brush or the pad and clean the joints thoroughly. You may need to repeat this process a few times while rinsing with water in between soap applications.
Once you are finished you can reinstall the joints if need be. If cleaning the pipe joints does not work, you may want to consider replacing them with new joints.