Earlier quoted context omitted.
Actually it doesn’t have to be A/C. If you have central air then you have a HEPA filter so just run the system’s fan.
Yes, I have no problems with the particulates, it's the temperature that's the problem with the windows closed.
It also gives you some protection outside, which is nice.
https://www.amazon.com/BROAD-Rechargeable-Electrical-Purifyi...