On top of that, some rooms don’t have proper cold air return to the furnace, meaning those rooms don’t get proper air circulation and can be the reason for a room being warm. I’m experiencing this right now. One bedroom has a cold air return on the other side of the wall, but nothing in the room itself, and it’s the hottest room in the house. I gotta cut an entry to that cold air return duct.

Cigarette smokers. Mostly because I hate the smell and smokers have their sense of smell damaged so much they don’t notice. And sometimes when it sticks to their clothing I just can’t be around them at all.