In just 4 hours fell during the night before yesterdays inspect what a mess poor home owners did not have a clue that their carpet was wet in front of the fireplace and all along that same wall for about a foot out from the baseboard. They stood with their mouths open when I brought out the old IR camera
Is your focus broken?
I had one like that a few weeks ago as well. Moisture was coming in from the chimney area and flowing along the wall while being absorbed by the carpet padding along it’s path.