I feel your pain. Ten years ago we were living in an old apartment, and my bedroom was essentially an attic, and as you know, heat rises, so my room was bottling up all the heat: since the apartment was really old, the air conditioning was inadequate - the super didn't allow window units, but said we could have a portable unit, so we got one for my room, and after installing it and turning it on for the first time, it too read the room temperature as being well into the 80s.