I recently purchased this unit. I had the plug on the drain for 5 weeks. It worked fine. Then, one morning a wokw to a puddle of water under the unit. I removed the plug and drained most of the water out. At that point, I connected a 5/8" drain tube as opposed to replacing the cap. That did not stop the leaking. It seems that the drain has a horizontal slit that goes back further than the hose can go and water leaks thru this. I thought it was a defect so I returned it to HD and replaced it with same model. I initially attached a drain tube, but it leaked right away. I placed the cap on and for now, it works fine. Also, I'm windering about the automatic shut off that is supposed to work when the reserve water tank is full. Any comments or help? kenb123@verizon.net