A good system like an AprilAire [1] will have a 4" thick filter vs the standard 1" thick filters. This allows much more filter area than a standard filter allow

A good system like an AprilAire [1] will have a 4" thick filter vs the standard 1" thick filters. This allows much more filter area than a standard filter allowing proper airflow even with a finer more restrictive filter medium. You can't just swap filters, the 4" thick one usually go in right before HVAC air handler intake rather than at returns. I have had an AprilAire installed for over 10 years in my HVAC when it was replaced last time, recommended by HVAC installer, its has worked very well and I do have my blower fan cycle constantly regardless of need for heat/cool to turn over and filter air. 1. https://www.aprilaire.com/whole-house-products/air-purifiers/air-filter-buying-guide https://www.aprilaire.com/whole-house-products/air-purifiers...