Good day to you! I think I have a gnat infestation in my house... specifically my basement. I'm not sure how they got into the basement. I do have a basement bathroom and a sink in the basement next to the washing machine. I also have a AC unit in a window that I thought they may be coming from. I've used the ACV traps and caught not a one. I do have a electric trap that catches many. but still they keep coming. And they are really fast too. How do i remove these guys? Any nudge in the right direction would be greatly appreciated.

from your description these could be either drain flies or fungus gnats. They both will be in areas of high humidity like bathrooms, laundry rooms and floor drains. Clean any floor drains with a long handled scrub brush especially a the line where the water stands. Flush with lots of water and about once a monty flush with water and bleach to keep them from coming back Using a dehumidifier will help stop or slow down fungus flys. Basements and floor drains just provide the right conditions. Running a fan to ciculate the air will help as well

Hello, don’t know if you still post on this thread. But about 3 weeks ago I started finding dead gnats all over my house. It was weird. And I noticed when I turned on the ac is when it was happening. So I stopped using my ac to see if it would decrease. What happened was that I stopped finding dead ones. But they were still living ones coming in somehow. I have the yellow sticky trap and they seem to be drawn to it. I have them in e wet room I put them low like near floor boards and that’s where I catch the most. Where are they coming from ? And how can I get rid of them? Any suggestions would be appreciated.

Typically gnats are associated with high humidity and high moisture areas, but necessarily free water. Not sure the cooling systems used in California versus here in Illinois, but if evaporative cooling is used then there can be opportunities for gnats to exist. Dips in duct work or water saturated insulation/deadening material inside duct work can be enough. If a system similar to here is used, the condensate pan may be plugged or at least not freely draining. If your cooling runs through a central ducting system, that explains why you are finding them everywhere. Any live gnats are just flying out and have limited distribution. More humidity lower to the floor with slightly cooler temps too, preferable environment. You may need to have the AC system inspected to find out if you have something malfunctioning or ducts that need repair.