Filters have a efficiency rating called MERV, ( Minimum Efficiency Reporting Value). The higher the MERV rating , the cleaner the air and the better the equipment protection. Control dust, dirt, and pollen with high quality filters and/or air cleaners.
If possible, shade the outdoor compressor unit. Air in shaded space is typically 5 to 6 degrees cooler than the surrounding air. Proper shading can be up to 10 percent more efficient over a cooling season.