Well, its like 32 degrees. The stove room is 68. The living room is 64, spare bedroom is closed office is 62 and me is 63. When it was 0* those rooms were in the 50s. Maybe my expectations are to highHow warm are your rooms and how warm are you expecting them to be? I saw mid-70s earlier for the stove room, what about the others?
I’d also go around with the IR gun to each room and find the cold spots. That might reveal something as well. Check along the walls at the floor, ceiling and windows. Also any penetrations in the ceiling.