Quote Originally Posted by _chelseaaa View Post
I got it from a guy at an expo, there’s only one vent. The room is pretty cool, around the low 70’s. There’s definitely cool air coming in through the windows. I’ve tried blocking them off with towels and hanging heavy curtains.
It wouldn't surprise me if the cold air leaking in through the windows makes the floor area colder than the rest of your room.

This is a terribly "redneck" solution, but I use clear plastic pieces cut from a painter's drop cloth, and clear packing tape, to seal up/cover my remaining old, poorly-insulated, single-pane windows remaining in my house (I'm slowly replacing them as finances permit). For under $10 in supplies per winter I figure I'm saving $40-50 monthly on heating bills by eliminating those drafts.