I don’t know how, but it seems like that air conditioning vents get really dirty, really easily.
It’s always annoying when this happens, but I know why. It’s because of all of the pet hair, as well as my own hair, and a ton of other dust and debris that get stuck in the ductwork and out into the air and A/C vents. Whenever I notice the HVAC air vents getting dirty, it’s really easy to fix. You could take a paper towel to get the dirt and dust off, however there is the chance that the dust will just fall to the floor instead of sticking to the paper towel. My most preferred method is to just get my vacuum cleaner and just suck all of the dirt, dust and other stuff stuck in the air vents. It just amazes me and disgusts me at the same time, watching the air vents go from a grey color, back to the white color they were supposed to be. It is really satisfying to watch actually. Just with a little bit of maintenance like this, I not only help my furnace system and cooling machine, but that also improves the indoor air quality a little bit. I would suggest you go room to room and check all of your HVAC vents, to see if they need to be cleaned. Some of the vents might be on the ceiling, so for those you’ll need a ladder to go and clean them properly. It can be a pain, but it doesn’t take much time and helps you in the long run.