Thanks, folks!
Splint, we do leave the door open. I also live dry, here in southern CA. I also shortened the drain hose, because the mfg says that if it's too far in, it can siphon back. That didn't help. Next is to add a drain line for the screen, and put a ball valve on it. Then I can drain it after every use. I have to run the clean cycle with bleach before doing any of my laundry, and the towels. Nothing like putting a "clean" towel to your face to dry it, and it smelling like mildew. I'll be at Lowe's tomorrow and will pick up what I need.