OK, so when my heater comes on, the master bedroom gets nice and toasty, as does the living room and kitchen/dining area. The 2 bedrooms on the other side of the house stay pretty cold. The air coming out of the register in the ceiling is warm, but there is almost no force behind it. The air is basically just leaking out of the hole. What the hell do I do?! My kid's room is friggin cold!