Miami is one of the few places where cooling runs most of the year. Concrete block houses in Hialeah, Kendall and Miami Gardens have outdoor condensers that rarely rest.
Near the water, in Coconut Grove and Miami Beach, salt air eats coils, so units wear out sooner. Condo units have their own air handlers, often in a closet, and a leak there reaches the neighbor below.
Humidity is the other enemy. A system that cools but does not dry the air leads to mold worries and calls. Power cuts after storms stress equipment too, and hurricane season, June through November, brings both tune-up calls before a storm and repair calls after it.