The house I grew up in was built in 1914 and I have no idea when the furnace was put in. It was a pot-bellied, coal burning contraption with large cylindrical tubes that sent the warm air to the upstairs rooms. I thought they resembled long arms which even made the monster (the furnace) seem more human. I remember on Saturdays when I was playing outside, the truck would arrive full of coal. The truck would back up to the side of the house and dump black coal into the small basement window that emptied right into the coal bin inside the basement. The coal bin was like a separate room in the basement near the furnace. I wasn't afraid of the coal bin.
I was always afraid of the furnace. I don't think it helped matters any when my oldest brother threatened to put me into the furnace. He opened the little door in the stomach of the beast and I saw flames inside. The coals glowed. That was enough for me. My brothers used to stoke the furnace by shoveling more coal into the center of the ugly beast. I also remember them taking the "clinkers" out to the alley. I haven't used that word in a long time. Clinker just doesn't come up in normal conversation.
Well, I had a bad dream about the furnace. I dreamed that I was playing alone in the basement. That would never happen in this lifetime. Anyway, in the dream the furnace started to chase me and I ran up the basement steps and through the kitchen to the back porch. My mother was hanging up clothes in the backyard and ignored me as I ran around her screaming. I looked back and the furnace was coming through the back door. (That also could not happen as it was way bigger than the doorway). Dreams are not always logical however, I was always afraid of that furnace.
When I was in sixth grade we got a new furnace. It was a large and boxy and didn't look like a monster. It didn't look like it had arms and I was never afraid of it.
I am sure there is a clinical name for an unrational fear of furnaces. I was also afraid of rivers as a child. Subject for another day.....