I have what I think are fruit flies that fly between my central air vents in my family room and they are driving me crazy. At first I thought they were coming from fruit left out in the kitchen (which is adjacent and open to the family room) but despite putting all food away and cleaning my drains/ trash etc. they persist. There always seem to be two or three flying back and forth and get in my face when I sit down. If I pour a glass of wine and sit down they find me immediately. Is it possible that they are living in my AC? They don't seem to be in other rooms, just the one, and we change the intake filters on the AC every year. Can anyone help me?

The possibility of fruit flies exists, but there are several other species of small flies that infest homes this time of year as they look for safe places to overwinter their eggs.

The easiest way to tell if they are fruit flies is to get a narrow necked clear disposable bottle, such as bottled water or cleaners come in, rinse it thouroughly, and leave a half inch or so of apple cider vinegar in it overnight. If you don't catch half a dozen or more, research
Fungus gnat - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Fungus_gnat)
Psychodidae - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Moth_fly)
Phoridae - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Phoridae)

One of these may be your culprit