Is this common? (Flowermate)

I decided to run my Flowermate a session with no flower inside. I've had it for about a month and I've probably only cleaned the chamber once. It's a little dirty, stained brown a bit by fairly regular usage but no visible residue at the bottom. When I ran a burn-off session, I noticed vapor coming off from the chamber itself. I just wanted to confirm, is this a regular thing? Is the vapor likely just from the residue from past use? I just want to make sure it isn't smoke. Thanks for reading! I'll provide a picture of the chamber and maybe a video in the comments.