A plumbing cleanout provides a convenient place to access a building's drain pipes to clear clogs and debris. You can remove a cap on the cleanout to supply the needed access. The plumbing codes of most localities require the installation of cleanouts during the plumbing rough-in during building construction.
A plumbing cleanout consists of the main body and a threaded cap. The body is usually the same diameter as the drain pipe where it will be installed. The extension is the portion of the body that the cap is threaded into and is designed to be easily accessible in the event of a blockage. The cap should be 2 inches above the level of the floor or the ground outside.
A cleanout may be inside a building or outdoors. A cleanout that is outside the building should have a cap visible within a few feet of the building's foundation. A cleanout located inside the building may be inside a wall or floor. A cleanout may be easily accessible in buildings that have a crawlspace or a basement. Cleanouts are usually in the drain where there is a 90 degree turn and positioned in such a way that when you remove the cap you can easily work on the blockage.
Removing the Cap
Place a large bucket under the cap if it is located inside the building to catch any liquid that may still be in the lines. Adjust a pipe wrench to fit the square fitting on the end of the cap. Place the wrench over the fitting and turn it in a counterclockwise direction to loosen the fitting. Remove the wrench and twist the cap off by hand.
Clearing a Blockage
A plumbing auger looks like a large power drill and it available for rent at home or plumbing centers. Turn on the auger and feed it into the clean-out extension. Some augers will extend automatically to reach the clog. Use a garden hose with a high pressure tip if you do not have access to an auger. Do not use a hose if the cleanout is inside the home. Coat the threads of the cap with pipe dope and tighten it into place with a pipe wrench to provide a good seal against sewer gas.