Old_Me
Emissary
well could be a low freon issue..Evap coils iced over? Sounds like refrigerant issue like you said.
could also be a plugged orifice tube (if home a/c's have that like on automobiles), or a clogged line, evaporator, or even a filter in the house. if the filter is clean, possibility still exists that the air chamber where it sits up on, has dust that got by the filter.
the condenser coil outside could be dirty, or clogged as well, with leaves, grass, bird feathers, dead rodents, or the fan on top of that condenser coil housing could be bent, missing a blade as well.
if running by a "fan belt", that belt can be loose as well......if it is the original, it will loosen up (stretch) over time, just like any other fan belt would.
all quick and easy things to check out.