The answer to 'P-trap constantly running' is that a P-trap that is constantly running or leaking is typically caused by a clogged or improperly installed drain pipe. The P-trap is a curved section of pipe under a sink or tub that is designed to hold water and create a seal to prevent sewer gases from entering the home. If the P-trap is not working correctly, it can allow water to continuously run down the drain.
Some common causes of a running P-trap include a clogged drain, a damaged or dried out P-trap seal, or an improperly installed P-trap. Homeowners may be able to fix a simple clog or tighten the P-trap themselves, but if the issue is more complex, it's best to call a professional plumber to diagnose and repair the problem.