First time poster here. I discovered a leak today only when the shower is running. Water is dripping out from the furnace access cover area outside, and the seam over the cargo access door on the same side. Happens with both hot or cold water running. I took the access door in the shower off, and there is no water leaks seen from there. Also, no leaks when the sink is running, so I believe it's in the shower drain - either the actual fitting from the shower to drain line, or in the trap fittings. Either that or a crack in the shower floor? Any suggestions on how to access the plumbing under the shower? Thanks!