Our house has forced air heating and cooling. The most annoying parts of it are dust and spreading of odors. You could just be finished dusting in our house and see a fine layer of it on furniture just a few hours later. Plus, if I was cooking something with garlic or onions, you could smell it all throughout the house when the heat or AC was on. We have a good stove vent, but our filter system in the furnace and AC was not the best. I called a place that upgrades HVAC in New York City after my neighbor told me about the HEPA and electrostatic filtration system he has. It is like those room air purifiers, but it works throughout the whole house.
The system has a HEPA filter that traps particulates that are very small. The filter before it is electrostatic and grabs a lot of dust and bigger particles. There is some kind of deodorizing thing that uses charcoal, I think, and there is also an ultraviolet light that kills bacteria and mold. My neighbor says their system makes their house a lot less dusty and a whole lot less smelly. It works every minute the heat or AC is on, and you can turn on the thermostat to the fan setting during the transitional times of year when it is not cold or hot.
When we got our system installed, it made it so odors did not spread throughout the house and there was no more dust just floating in the air. Have your ever looked at a sunbeam coming through a window and saw dust particles? Our sunbeams look a lot cleaner now. It is nice to know we are not breathing all of that indoor air pollution in any longer. The HEPA system has also greatly reduced the pollen count indoors, and this has greatly helped with my seasonal allergies.