I just recently moved into a house in February. It is 17 years old and the HVAC/Furnace is original to the house. I had multiple inspections done, so I know that the AC unit's condensation line clogged and the pan overflowed causing a leak in the ceiling. You can see where they had to patch the hallway ceiling from the damage. The house was vacated at the end of August 2013 started looking at this house in November 2013, closed at end of January 2014, and have been living here since February 10th. We just now noticed a brown stain in the corner of the ceiling in the same area as the HVAC that is in the attic. Obviously we have just been running the gas furnace not the AC since it's now April 1st. We have had a lot of ice and snow for being in North Carolina. The inspections never came up with any current leaks and all stains seen at the time were tested for moisture. I read that stains can seep back through paint. Does this stain look "old" or like new water damage? (I am a first time home buyer, so of course I am a little freaked out)
This picture was enhanced to make the stain a little darker to show where it is.