Long hot spells leave little room for a restricted outdoor coil.
An air-conditioning system has to shed heat through its outdoor coil. In Tye, windblown dust, grass clippings, seed fluff, and other debris settle into the narrow spaces between condenser fins. Once that face becomes matted, air no longer moves freely through the coil, and the system has a harder time releasing heat outdoors.
That restriction matters most through extended hot weather. The compressor then works against higher pressure while the system has less cooling capacity available indoors. Cleaning removes the debris without crushing delicate fins or forcing dirt deeper into the coil, and protects the electrical components around it during the work.
Indoor coils need attention for a different reason. Fine dust reaches them when filtration is poor or when return-side leaks draw unfiltered air from unconditioned spaces. That buildup restricts the blower much like a clogged filter does. We also check the drain pan and condensate flow, since buildup around a wet indoor coil contributes to drainage problems that lead to overflow or system shutdowns.