This is my first winter in this rental home. Our furnace is in a utility closet that is accessible only from the outside of the home. The home is a rambler with a crawlspace and all of the ductwork to the vents is in the crawlspace (almost all the registers are on the floor). The "cold" air return is in the ceiling of the central hallway. I've never seen a return in a ceiling, but to each his own.
The mystery is that every time the furnace turns on, it pulls cold drafts from every imaginable crack or crevice in the house. For example, if you put your hand next to the door sill, then the moment the blower turns on, a strong draft of cold air starts coming in. This seems to be true in every room, including the utility closed where the furnace is located.
What is causing this low pressure vacuum and how can I fix it?