Apparently I must have a hole in the duct work leading to my sons room. Within a month, his walls and furniture are so dusty, you can write your name in it. This only happens in his room and the main intake filter isn't that dirty when I change it each month. I went up in the attic and can't see any holes, but I don't think it would take a really big hole. Is there an easier way than disconnecting the duct work and shining a flashlight inside of it? My heat pump is in the attic and there is not a lot of room to maneuver.
Thanks