I got home from work Wednesday, dropped off some papers on my dining room table. The carpet was wet, which was a surprise. I soaked it up, looked all over trying to figure out where the water came from, but found nothing.
The same thing happened Thursday. I recently did laundry so I thought perhaps the washing machine was leaking. But after a search, nothing obvious in the utility room. The carpet was wet all along the border with the tile.
Friday morning the carpet was wet again, so I called a plumber. He came over and quickly diagnosed the problem as an A/C drainage issue, so the normal drainage leaked out from the return vent to the dining room. It seems there is a clog and the unit needs to be cleared. So that'll happen Monday. In the meantime, I guess I'll run the A/C less, but in the middle of August in Florida, not running it isn't really an option.
If the carpet is too messed up and needs to be replaced, I plan to tile or hardwood floor the dining room. I don't really like carpeted dining rooms anyway - every piece of dropped food would stain it.