The answer to 'drain constantly running' is that a continuously running drain is often caused by a problem with the drain stopper or the drain itself. This can be due to a malfunctioning or stuck drain stopper, a clogged drain line, or a problem with the plumbing fixture.
Some common symptoms of a constantly running drain include the sound of water continuously running, a drain that won't fully close, or a drain that drips even when the fixture is not in use. Potential solutions can include adjusting or replacing the drain stopper, clearing a clogged drain line, or repairing or replacing the plumbing fixture. In some cases, the issue may require the assistance of a professional plumber, especially if the problem is with the underlying plumbing system.