It’s also best to help keep Home windows closed, so the unit isn’t cleaning the air from outside or other portions of the home. And make sure airflow to the machine isn’t obstructed by home furniture, curtains or other objects. "HEPA-like" filters have not been Qualified to meet that normal. https://elliot5bksa.activosblog.com/30459637/helping-the-others-realize-the-advantages-of-best-air-conditioner-cleaning-company-in-qatif