Pungent smell from air conditioning vents indicates wiring problem or accumulation of mold. Therefore, this needs to be taken care of IMMEDIATELY!
These are just the main things to look out for that will help you feel more confident in keeping up with your home and making sure everything is running smoothly.
The best way you could care for your AC system and ensure a long healthy life for all, is to have timely maintenance and repair checks so don’t hesitate to call!