If you have recently had a new disposal installed, the installer may not have removed the knock-out plug that allows the discharge to pass through. This will cause the discharge to back up and out of the air gap on your sink. (Thinkstock)
If you have recently had a new disposal installed, the installer may not have removed the knock-out plug that allows the discharge to pass through. This will cause the discharge to back up and out of the air gap on your sink. (Thinkstock)