A childhood belief about basements

I used to believe the Devil himself lived in the heater in our basement. We had this huge Victorian rowhouse with a strange heater that was much, much larger than modern ones, and it had a little metal door on the side. When on, the door was occasionally shudder open and closed, and my mother reassured me it was only Satan trying to get out. Parents! I lived in fear until I realized the heater was completely empty of demons, but until the day we moved, that damn thing always kind of freaked me out.